Monday, October 31, 2011

Cold-Formed Steel Shed Industry: part:#1

Sample drawings of framing plans for cold-formed steel shed, partially automated by the scripts(*.scr) mentioned in earlier blog, then extensively modified using manual CAD editing, using AcadLT 2000, to match the custom features of the project. Project is from a few years back, and drawing title blocks have been removed so as not to identify the project, client and supplier. The drawings have additional detail on them compared to that required for development approval, so as to assist with workshop detailing. The cold-formed shed industry typically does not produce drawings beyond scribble on the back of an order form: not for development approval and not for fabrication. The industry typically has salespeople and possibly estimators sketching out what they believe is required. The whole benefit of the cold-formed steel shed industry is that need little infrastructure, and simply need to fill in some purlin detail sheets and send of to local roll former of c-sections, and have a bundle of fabricated steel delivered straight to site depending on connection details. This typically fine for the smaller sheds but for larger warehouses with office space it is inappropriate.

In the past we typically worked with the suppliers and manufacturers and couldn't get them to change, very little interest in their product. Then  one day a steel erector turned up, he was unhappy about various issues with construction, and wanted to refine the design. Also turned out that supplier/manufacturers often failed to deliver all required parts for construction, and unable to get these parts from the suppliers on basis they contended that the parts not required. We recommended that the steel erector insist on workshop drawings being produced. The shed suppliers wouldn't provide, and workshop detailers not able to fit in with the nature of the shed industry. The result was the workshop detailing returned to my office, along with designing the sheds on a project by project basis, rather than the typical industry approach of having standard calculations and relying on local council to request further information to get calculations which match the proposed shed.

As long as the shed stays as a simple plain frame, then can analyse it using Kleinlogel formula in MS Excel, and the calculations are dropped to a few minutes. The time consuming effort is producing the framing plans for development approval, and the workshop details. Connection details are basically the same from one project to the next, and standard drawings simply need project name changing, though each new project may introduced additional detailing.

Now software like Autodesk Revit structural, or Tekla Structure, and other BIM  software, may be the ideal tool for such project: however they are far to expensive to justify given the amount of work involved and the relative simplicity of the structures. Also in terms of developing tools to improve point-of-sale decision making in the industry, tools like AutoCAD are too expensive to use as a graphics engine, whilst Multiframe is too expensive to use as an analysis engine. So MS Excel/VBA is typically the product to choose with possibly some low end CAD package, alternatively use the Excel shapes layer, and draw in Excel itself.

So slowly developing in-house tools to handle custom projects, whilst also developing tools which ultimately can be used by sales people at the point-of-sale. The objective is to reduce the problems caused, by bad design decisions at the point-of-sale. In particular the buildings that the industry can supply simply do not meet the needs of the buyers. But this is not identified until council rejects the suppliers development proposal, and requests further information, then everyone turns to consulting engineers to get calcs-for-council, as if that was all that was needed.

So the objective is to develop low cost automation tools based on simple parameters, which flags the need for custom engineering at the point-of-sale. Currently these buildings basically  sold like cars, except can ask for three of the wheels to be removed to cut costs and the sales person will say yes we can do that.

The real issue is developing a simply interface, at no point do want the sales-people operating a CAD package, but need to know the custom requirements for doors along the length of the building, and also know the different gable-end framing requirements. Also need to expand beyond the simple gable, to allow for double span, and the American barn type structure (gable, with lean-to each side).

So currently have a collection of different tools written in Excel/VBA, also some of which I originally wrote in Turbo C and others in Delphi. A part of development problem is deciding on application language, a great deal has now been written in Excel/VBA, but MS Access maybe better, and better again with respect to data storage and suitable user interface. In particular I can program a treeview in for my bill of materials (BOM) but not in VBA. On the otherhand I don't really like Basic programming language, its just that VBA is built into so many applications: and controlling anything and everything from Excel/VBA has been so convenient. For speed developing the Excel/VBA, and AutoCAD LT approach, with Microstran and Multiframe data file generation, seems to be the way to go, then slowly remove dependencies on other applications, and make stand alone. Part of which requires developing a 3D frame analysis program, already have 2D, but ultimately going to need it to be 3D.

Anycase currently finding all the bits and pieces cumbersome to use. So given that the purpose of this blog is to document the background as to how things develop, I thought I would document the current process, whilst I figure out in which direction to go and what to program next.

Fig:S01: Footing Layout

Fig:S02: Framing Plan

Fig:S03: Elevations:1

Fig:S04: Elevations:2

Fig:S05: Sections/ Portal Frames

Fig:S06: Gable End Wall Detail Section: Office End

Fig:S07: Gable End Wall Detail Section: Rear

Foot Note: Sample drawings printed to pdf file using pdfactory, then borders and title blocks removed, by taking snap shops using Bluebeam, and saving to jpeg using MS Paint, then file size reduced using Microsoft Office Picture Manager.

Related Posts:

Cold-Formed Steel Shed Industry: part:#2 : Dimension & Geometry (Acad LT)
Cold-Formed Steel Shed Industry: part:#3 : Summary of other requirements

Feasibility of Cold-formed Steel Shed (Simple Structural Software Application)

Other Blogs:

Other Information:

Monday, October 24, 2011

Structural Engineering

The art of moulding materials we do not really understand
into shapes we cannot really analyze,
so as to withstand forces we cannot really assess,
in such a way that the public does not really suspect.

Professor E. H Brown, (1967), Structural Analysis, Vol 1, Longmans, Green & Co.

Sunday, October 23, 2011

Manufactured Structural Products And Simplified Wind Classification

Manufactured products are typically classified into size ranges and/or performance grades. It is generally not practical or economical to have infinite variety of product offerings. Further more it is generally not economical to base the size ranges on an arithemetic series, and therefore size ranges are typically based on a geometric series usually a Renard series.

Buildings and other structures are typically designed and constructed one-off, rather than purchased off-the-shelf. However there is an increasing number of off-the-shelf buildings becoming available, the primary reason is that people want buildings not pictures of buildings. Unfortunately the industry is poorly served by consulting civil engineers, who are focused on one-off construction, and the need for consideration of site specific features. Whilst there are site specific features to consider it would be nice if the output of civil engineers actually reflected such custom consideration: rather than implementation of some routine solution and calculation of some point-value. Structural sections, bolts and a variety of other components all have standardised sizes and performance grades. All such components have critical characteristics for which minimum and/or maximum values can be determined for a specific generic application: there is no need to keep calculating from one project to the next: its a waste of time and paper. Simple selection criteria are required based on the controlling characteritics of the product. One such characteristic is the wind load.

To the wind loading code AS1170.2, a regional wind speed (VR) is selected: this is typically the wind speed experienced 10m of the ground, over terrain of category 2 (M[z,cat]=1): typically a local airport. This regional wind speed is then adjusted to match the site specific features, by the use of multipliers for terrain category (M[z,cat]), topography (Mt), shielding (Ms), and direction (Md), to give the site specific design wind speed (V[sit,beta])at a given reference height (z).

V[sit,beta] = VR Md (M[z,cat] Ms Mt)

The maximum from several different directions then becomes the design wind speed (V[des,theta])

This can then be converted into a reference pressure (qzu) as follows:

qzu = (0.5 rho[air]) V[des,theta]^2

The design pressure (p) on a given surface then obtained from:

p = qzu. Cfig Cdyn

{Example  Calculation sheet can be found at ExcelCalcs: schWindAssessment}

Where Cfig is a pressure coefficient dependent on the location of a given surface with in a given shape and configuration of building, and Cdyn is a dynamic response factor. From these formulae it can be seen that there are potentially an infinite number of pressures that a range of products need to be designed: not very practical. However for a generic application the values of Cfig and Cdyn are more or less lock in by AS1170.2, so the main variable is qzu, from one site to another. Whilst there are several factors which go into calculating qzu, the same value of qzu can be determined from a variety of differing inputs. Therefore wind load classes can be defined by the maximum value of qzu permitted in the class. And given that there is a minimum ultimate strength design wind speed of 30m/s, there is also a minimum value of qzu, which for the sake of argument could be called wind class N0. From the minimum then need a method of defining other classes. The basic principle adopted for AS4055, barring some historical anomalies and rounding, is that each wind class applies a pressure 1.5 times greater than the lower class. However due to the anomalies that doesn't quite hold true. Anycase 6 wind classes are defined N1 to N6, defined by ultimate strength design wind pressures (qzu), or otherwise by the associated design wind speed Vzu=V[des,theta]. Since tropical cyclones also impose fatigue issues, for the same wind speeds there are 4 cyclonic classifications C1 to C4.

Note that AS4055 is simplified wind loading for housing. The wind classification system itself does not have anything to do with houses, nor the dimensional constraints in AS4055 nor the pressure coefficients in AS4055: it would be far better if removed from AS4055 and placed in AS1170.2. For anything other than housing: AS1170.2 should be used to determine Vzu or qzu, and assign a wind class.

When defining a product, design to qzu determined from AS1170.2, then assign nearest lowest wind class. When selecting a product, assess the site to AS1170.2 and assign the nearest highest wind class. It should be noted that local government authorities (LGA's) produce wind speed maps for housing, a site classed as N1 for a house may not be classed as N1 for some other structure. A site can only be classified with respect to the reference height (z) of the structure. A three storey house is likely to fall outside the scope of the wind speed maps and the simplified tables in AS4055. Also the wind speed maps are roughly derived, so that it is beneficial to get a site specific wind load assessment.

For many N1 sites on the maps are at the lower end of wind class N2, and difficult to prove the full shielding which puts them into the lower class. However many of the N3 sites are near the upper end of wind class N2. In terms of timber framed housing to AS1684.2, this doesn't make much of a difference for there are only combined span tables for wind classes N1 and N2, member size largely controlled by live loading requirements rather than wind loading. However, the wind classification affects the requirements for lateral bracing and tie-down systems. The tie-down system mostly affects the connections, and that can be a matter of personal design philosophy. Not connecting the members to achieve the full capacity of the installed members, may be considered extremely wasteful. For eaxmple connections in a wind class N1 house have little to no reserve capacity for additional wind load, as may be imposed if a carport or verandah is attached to the house at some future date. {Contrary to popular opinion: you cannot attach any size carport or verandah you wish to a house structure in wind class N1. There is no reserve capacity, and chances are cannot attach one at all.}

Anycase the wind classification system permits simple selection, for a variety of manufactured structural products (sheds, carports, verandahs, houses, fences, windows, doors), however, determination of wind class should be by using AS1170.2 not AS4055. Alternatively additional design aids should be created to further simplify the assessment.

More importantly manufacturers should produce full technical specifications. Saying to AS1170.2, to AS4055, or to AS1684 is meaningless. The specific's of these codes should be identified in technical specifications for the product. In particular the internal and external pressure coefficients, or nett pressure coefficient used should be identified in the specification. Pressure coefficients do not vary between cyclonic and non-cyclonic regions. Those hanging baskets swinging from the pergola can equally well be thrown through the window in a cyclonic or non-cyclonic region. Determinining internal pressure coefficients is a complicated matter of assessing the risks associated with various states-of-nature that a building may experience. Assesssing all the states-of-nature is time consuming, so the simplest approach is to assume the building envelope is breached and that high internal pressures are generated. This is not however always conservative, since for a framed structure, it results in zero loading to the wind ward face. On the otherhand if high internal pressures do produce the maximum stresses in the frame it is not necessarily economical. The purpose of manufactured structural products is to be economical and provide fast supply.

The building code of Australia (BCA) requires consideration of the hazard to life, as well as the loss of amenity. Not having the amenity in the first place, may be fast becoming the major concept of loss. The magnitude of load has very little to do with the hazard to life. The design load always has a probability of being exceeded. so considering Tropical Cyclone Tracy, steel roof cladding was ripped from building and its sharp edges became lethal. All the cyclone testing of cladding and the cyclone washers, and the increased design loads, have failed to remove the sharp edges from the cladding. When the design load is exceeded as it will be one day, the hazard remains. But the population is going to become complacent about us having cyclone proof buildings, which we don't have: they will believe they are safe when they are not.

Safety is not a quantitative issue, it is a qualitative issue. When and how the structure fails when the design load is exceeded is the primary issue of design which is currently neglected. The current magnitude of design loads are largely determined by insurance councils and government with respect to the cost of replacing structure, not the hazard to life. Wind borne debris is a problem, but as indicated when the design loads are exceeded, it is still going to be there. The exercise is partly one of balancing inconvenience against disaster. Disaster arises when the community is not able to recover without external assistance. It should not be necessary for all parts of a building to have the same resistance nor to survive the same event. Many buildings, and many rooms within buildings are non-essential, and loss of such is not a major hardship. There are certain core facilities within houses which contribute to the quality of life in a modern city, these are primarily kitchens, bathrooms and laundries. Most other rooms in a house can be lost. More over buildings can be designed with weatherlocks which control the internal environment.

Another important issue to understand is that the BCA structural provisions are largely based on ultimate strength. That is stresses are permitted to exceed yield strength, and enter into the plastic behaviour zone of the material. This can be identified in the codes by the change from elastic modulus(Z) and use of plastic modulus (S), and the change from yield strength (fy) and the use of ultimate strength or fracture strength (fu). Materials are not expected to under go elastic recovery when the load is removed, they will remain permantly deformed even fractured. Probabilistic design permits less than or equal to the breaking load, it does not have to be strictly less than. The breaking load itself is an uncertain quantity which may be greater than the value used. The BCA uses 5th percentile characteristic strengths. After the structure has experienced its ultimate strength load it may have collapsed and ceased to be serviceable. This is important, a building is not designed to provide safe shelter during a hurricane, unless it is a post-disaster facility which is to remain serviceable after the event. After a design level event a normal building is expected to be no longer serviceable and to need replacement. The primary concern for the design level event is keeping the building anchored to the site, preventing it from becoming airborne debris. It is not the intent to keep it in service and operating.

For many years now the shed and garage industry has had members complaining about not being able to compete because there are those using internal pressure coefficients lower than the standard AS1170.2 specifies. Problem is AS1170.2 doesn't specify a value, it specifies a methodology for determining an appropriate pressure coefficient. That individual businesses in the industry cannot compete is largely because they rely on external consulting civil engineers, and otherwise know very little about structures and manufacturing or industrial engineering. Put simply they are mainly poorly designed businesses with poorly designed and even more poorly specified products. The businesses are also over loaded by sales people who get paid commissions to sell a product they of which they have zero understanding. A properly designed business could use significantly larger structural sections than most are using and wipe the majority of the suppliers off the map. The size of structual section has little to do with whether can compete or not.

So the Australian Steel Institute (ASI) shed group publishing documentation opposing the use of the wind classification system merely compounds the problems in the industry. The wind classification system is specifically for these types of manufactured products, and is far better to refer to wind class N1 or N2, than to refer to TC3 or TC2. The latter only gives consideration to one of the site characteristics whilst the wind class considers all the wind critical characteristics. To reiterate, AS4055 is for housing the wind classification system it defines is not limited to housing: but AS4055 can only be used to determine the wind class for housing, it is necessary to use AS1170.2 for other structures.

Damage to sheds during tropical cyclone Larry, and tropical cyclone Yasi, is not all together indicative of low quality non-compliant buildings. Many of the photos show the sheds collapsed, but it also shows the sheds still anchored to the original site: basic objective achieved. The BCA does not specify serviceability requirements, that is left as a subjective judgment for the designers and end-users, relative to the specific application.

One major problem with the shed industry is it runs around declaring their product complies with the BCA. Who cares? The product is required to comply with the BCA, so just provide the BCA evidence-of-suitability which demonstrates it complies. If it merely complies with the BCA then it is the lowest quality product permitted in the market. So forget about marketing BCA compliance, market how the product exceeds the BCA and provides higher levels of serviveability. We may not have tropical cyclones in South Australia, but we do experience tornadoes in the remote outback. Tornadoes are typically outside the scope of the BCA, but still need to be designed for. Design is not about code compliance it is about making the product fit-for-function, whilst giving due consideration to uncertainty and variability in its use and manufacture.

Now part of the problem is a failure to understand, that the fundamental law governing all supply is that for fair trading which requires goods are suitable for purpose. Once a product is released to the market or into the environment it will be used for all manner of purposes beyond the intentions of the designers. Technical specifications and product literature therefore need to make explicit the suitability of the product and the evidence-of-suitability. Shed manufacturers compete on price because one piece of junk is the same as any other, there is no added value for the higher price.

The building industry is not serious about the quality and performance of its products, it is largely why it is regulated. Buildings are failing because the component parts are not up to specification, and that is largely because the specifications of the major product itself is lacking.  Australia's relative isolation, and often monopolistic enterprises has seemingly resulted in many specifications being based on assumption. For example steel always from BHP, therefore don't really need to specify in detail. Coldformed steel sections always from Lysaght, so similarly don't need to specify in detail. This however is no longer the case, and those cheap c-sections are probably half the price because they are made from steel with half the strength. It is not the internal pressure coefficients that the ASI shed group should be concerning itself with. The products supplied need proper technical specicifications. Part of which requires putting  wind class N2 windows, along with wind class N2 doors, in a wind class N2 shed, on a wind class N2 site.

All the manufacturers need to get up to speed with the wind classification system, and the ASI shed group shouldn't be advising, near mandating that the wind classification system should not be used. Doing so makes te ASI shed group part of the problem. Door and window manufacturers need to provide their products with proper technical specifications. Due to the requirements of the glazing code, windows likely to be compliant, but door manufacturers do not yet appear to be paying any attention to the BCA. The doors to your house as well as the doors to your shed are highly likely non-compliant with the BCA. Consequently doors can be blown of their supports at less than design wind loads and lead to the development of high internal pressures not otherwise accounted for. Basically the economical design of the building is not taking into consideration the failure of the industry's ability to supply doors to a technical specification.

For a simple analogy. The walls to sheds have frames at 3m centres, with girts spanning 3m metres typically spaced less than 1.2m, the ribs in the wall cladding span the 1.2 m between girts. The roller doors are typically 6m wide, no frame behind, the ribs of the door cladding span 6m. The door clearly has no where near the resistance as the adjacent wall: the door is the weakest point on the wall. The wind will push the door in, causing it to balloon, until it stretches so much it slips from the door guides and is then torn from the building, at which point high internal pressures occur in the building and will end up loosing more than just the door. Make sure the doors are compatible with the specification of the shed.

Complacency is another problem in the building industry. People don't want any hassle, they go to shed manufacturers because there is an expectation that all design problems have properly resolved in the past. So delays because this door not compliant are typically over looked with, just get it finished: a doors a door. This is a suppliers problem. The supplier is supposed to have designed the product and be ahead of the local council and regulating authorities, not behind. There will always be delays experienced during development approval, if rely on the council to advise what regulations have to be complied with. The designers task is to assert which regulations are relevant and that they have been complied with. Sales people are not designers, and custom manufacture does not equate to custom design. If the shed supplier does not employ design personnel on staff, then buyers should seek the services of an independent consultant. Suppliers should seek to inform and educate the public.

Anycase I will essay shed design in more detail at a later date, along with design-for-failure. Other writings on wind loading to AS1170.2 with comparisons to ASCE7-05 can be found in the SEAint archives.

SEAint Archives:

Sunday, October 16, 2011

Programming/Automating #Autocad LT

As far as I am aware the main reasons for opting for the full version of Acad are:

1) AutoLISP
2) COM automation
3) Database connectivity and SQL
4) Extended data
5) Complex entities/objects, 3D and otherwise

The seemingly most dominant reason that full Acad is chosen is because it is programmable through AutoLISP. The common myth is that AutoLISP is required to program AutoCAD. Since AcadLT does not have AutoLISP it is not programmable or customisable. Wrong!

AcadLT can be customised and its is programmable without any tricks or add-in LISP engines. Forget about the pretty toolbars, AutoCAD has a command langauge, and supports script files for those commands. The command language and script support is not as powerful as that in say the old DBase II/III, but it is none the less available.

The common criticism aimed at scripting is that it cannot do anything. For example to draw a line, the script would be:

Line 0,0 1000,1000

where as in AutoLISP it would be:

(command "line" pt1 pt2 "")

Where pt1 and pt2 can have any coordinates desired, thus the AutoLISP script can draw different lines, whilst the command script can only draw one line. However, the AutoLISP script is part of a much larger program which determines the values of pt1 and pt2, and instead of sending instructions to the Acad command line, it could equally well write the instructions to a file as follows:

(write-line (strcat "LINE " (ptstr pt1) " " (ptStr pt2) " ") fp)

Where (ptstr) is a user written function to convert the point coordinate lists to text strings, which can be written to a file (fp). The resultant plain text file can then be excuted from within Acad or Acad LT via the run script command. For simplified usage the script can always be written to the same location and file, such as default.scr, and this script can be executed from either a menu macro or toolbar button: once again in either Acad or Acad LT.

'_script default.scr 

Now such plain text files containing Acad command line instructions can be generated by any available programming language. On old MS DOS machines the most readily available programming language was GWBASIC, but other high level programming languages like Turbo Pascal and Turbo C may have been available. In the world of Windows XP and higher, every machine has available windows scripting host and can run VBscript or JScript.

For example in VBscript, can replace the AutoLISP instruction with:

fp.WriteLine("LINE " & ptStr(x1,y1) & " " & ptStr(x2,y2) & " ")

However most offices have MS Excel installed on most machines, and a few may have access to MS Access, in which case vba can be used to generate scripts. Script instructions can be generated in an Excel worksheet then copy/pasted into a text file, and run by the script command, alternatively the instructions can be pasted directly to the Acad LT command line. Similarly queries in MS Access can be used to generate a sequence of script commands either pasted to a file or direct to the Acad Lt command line. This approach is useful when converting simple data into graphics.

Example of Coldformed steel section generated from script pasted to Acad command line, from Excel worksheet. Worksheet can be found here.

For more advanced automation Excel/vba combination provides the means of collecting input in the worksheet and then writing a script file based on this worksheet data. In vba the typical script would be something like:

Print #fp, "LINE " & ptStr(pt1) & " " & ptStr(pt2) & " "

Where pt1 and pt2 are coordinates stored in a data structure as follows:

Public Type TCoord
  x As Double
  y As Double
  z As Double
End Type

To avoid keep writing the instructions for a line the following subroutine can be defined and used.

Public Sub write_line(fp As Integer, pt1 As TCoord, pt2 As TCoord)
  Print #fp, "LINE " & ptStr(pt1) & " " & ptStr(pt2) & " "
End Sub

call write_line(fp, pt1,pt2)

Similar subroutines can be written for other commonly used Acad LT commands. By building a library of such commands, it is possible to simply convert the program from one CAD package to another simply by rewriting the library to suit the CAD package. That is the main program written uses the users own subroutines and data structures, and should never need rewriting, but the library can be converted to use the data structures, objects and methods of a chosen CAD package. For example write libraries for scripts, DXF, Acad COM automation, TurboCAD, DesignCAD, MultiFrame, even the Excel shapes layer.

Now the problem with the script is it cannot select Acad entities, nor points. Many AutoLISP routines simply pick a single point on the screen then generate a parametric detail about this point. Most of the time (0,0,0) is a good enough start point and a new file is the place to start drawing, therefore no point needs to be selected. By generating a new file, and using xref to reference this file into the primary drawing, interaction with the Acad drawing editor can be minimised. Unless using handles and links to an external data base it is seldom necessary to modify entities. The primary objective is to automate drawing production, not interact with the drawing editor. If a full set of drawings for some parametric object can be generated in a few seconds there is no need to revise or modify the previous: simply regenerate using the modified parameters. Further more if critical parameters start out in Excel and are used to generate a drawing, then there is no need to extract such information from the Acad drawing database.

Interaction with the drawing editor is not highly productive, nor are dialogue boxes. A common flaw with AutoLISP routines is that they have dialogue boxes collecting mutiple parameters. The number of parameters collected by these dialogue boxes exceeds the number of parameters used by engineering. The problem is that engineering calculates the other parameters, used to specify a part. Due to the division of labour between drafter and engineer: the drafter draws and the engineer crunches numbers, there is consequently a lack of integration in the design activity.

It is more productive to write the AutoLISP routines without dialogue input boxes, rather write as subroutines requiring passing of parameters. Then write additional subroutines using dialogue boxes to collect the parameters and call the routine which does the actual drawing. The reason for this is so that the drawing routine can be used in much larger drawing application. Just as machines and buildings are made from component parts, also is a drawing using blocks and xrefs, and similarly a computer program using functions and subroutines. Just as blocks simplify building large drawings, so to do subroutines simplify writing large programs.

The first use of a drawing subroutine, may be to call it from a routine using dialogue boxes to collect all the drawing parameters. A future use may collect far fewer drawing parameters and calculate the rest. But of far greater value is the potential to string multiple subroutines together in sequence to draw something much larger and more complex from a few simple parameters.
Similarly, if this can be done using AutoLISP it can equally well be done using Excel/vba and the generation of scripts. What is more without the use of Acad or Acad LT, an engineer or other designer can generate a series of scripts in a common location, these scripts are then executed by the drafter using either Acad or Acad LT.

Excel/vba can also be used to grab a list of files, either drawings (dwg), DXF and then execute a set of script commands on each of the drawings. Similarly vba can get a list of scripts, and combine them into a single script to be launched in Acad LT. An alternative approach is to execute each script one at a time by calling Acad LT with command line switches, unfortunately with Windows multitasking causes a a timing problem. It is however the approach that was taken with Acad when using MS DOS. It was the failure of my Turbo C multiScripting program in Windows using Acad LT which led me to experimenting with generating scripts using QuattroPro spreadsheet with which I could easily grab a list of file names.

To launch Acad automatically from an application and run the script call Acad using command line switches, for example.

"C:\Program Files\AutoDesk\AutoCAD LT 2000\aclt.exe" /b default.scr

This can be configured in an Excel worksheet, so that can vary CAD applications used and the script names used. More samples can be found here.

Here is some sample output generated by scripts (*.scr).

From a few parameters steel framing plans, elevations and section for simple building generated in model space and paper space, all text with exception of grids placed in paper space. The above view shows the model space 2D stick diagrams, and the lower view a close up of the framing plan.

The following was originally written using DesignCAD, generating a 3D stick diagram of a shed, but then translated to use Acad scripts and draw more detailed elevation.

Simple stick diagram above. Below, model with detailed elevation, and permitting any number of spans.

The following is a close up of the knee connection.

A limitation of Acad Lt is not being able to generate 3D elements. I have used Lights for analysing tension membranes, and whilst it generated an Acad Script file, I was unable to run the file in Acad Lt since it could not create the 3D face elements, whilst intelliCAD 2000 used a different set of parameters to draw 3D faces so the script was incompatible. I therefore modified my Acad script library to use the intelliCAD COM objects. To produce the following, which is viewed in Acad LT.

I could have written the program using scripts in intelliCAD, but I used the opportunity to try out COM automation. The program reads the results from Lights, and then shades membranes elements in tension green, and elements in compression red. It is all on layers, so the membrane can be switched off, and the tension and compression elements of the supporting cables can also be viewed.

Another use of scripting is a simplified geographical information system (GIS). The following made use of MS Access, which was used to count the number of projects in a given area: mainly a UBD map. This data was then transfered to Excel, where a vba macro further sorted the data and generated a script which inserted a block on the appropriate layer. Red blocks represent areas with most projects, and paler blue blocks represent areas with least projects.

Each square represents one map from the UBD Adelaide street directory. The vba routines translate UBD map grid references into Australian Map Grid (AMG) coordinates so that can be located in Acad by (x,y) coordinates. In addition to the coloured blocks. circles were drawn at more localised positions, with the size of circle reflecting the number of projects in the area. The reference grid on each UBD map is about 250m x 250m, so objects typically located at the centre of these grids. For many things don't require the use of a fully blown GIS, since only concerned with relative distances between locations. For example nearest neighbours and hinterlands, or catchments of common facilities like shopping centres, hospitals, business competitors. The map shows that a lot of our work is dependent on the North East Road. It doesn't show projects outside the metropolitan area spread around the state and the country, and the occasional few outside the country. For an alternative GIS can take a look at MapMaker gratis this I have experimented with to generate contours whilst in the trial period with the professional version. The contours being for soil heave, caused by reactive clay soils. We have collected lots of bore logs over 16 years, and therefore, it should be possible to produce a contour map. At the moment I don't have subroutines to generate contours, but have found routines for generating Delaunay triangles, though generating Voronoi polygons would be even better for assessment of catchment areas. This far have written Acad scripts to do the triangulation, the rest is for a future date.

Any case if automation is the primary objective, and doesn't involve creation of 3D entities, then Acad LT can be used to automate a considerable amount of 2D work, or if stick diagrams are all that is required then it can also automate 3D models.

Recommended Reading
1 Microsoft Press (1997),"Micosoft Office 97 Visual Basic Programmers Guide", Microsoft Press
2 Jim Boyce, et al (1997), "Using Microsoft Office 97 Professional: Special Edition", Que
3 George Omura (1989),"AutoCAD instant Reference", Sybex
4 C W Sharp and W W Hamm (1989),"AutoCAD Advanced Techniques",Que
5 D Raker and H Rice (1990), "Inside AutoCAD: 5th Edition (metric)",New Riders Publishing
6 J Smith and R Gesner (1989),"Customising AutoCAD: 2nd Edition",New Riders Publishing
7 J Smith and R Gesner (1989),"Inside AutoLISP",New Riders Publishing
8 George Omura (1990),"The ABC's of AutoLISP", Sybex
9 Dennis N Jump (1989), "AutoCAD Programming", TAB Professional and Reference Books
10 AutoDesk(1995),"Users Guide: AutoCAD LT Release 2 for Windows",AutoDesk
11 Acad LT on line help system.
12 Burchard, Pitzer, Soen, et al (1997), "Inside AutoCAD 14", New Riders Publishing
13 AutoDesk(1999),"Getting Started: AutoCAD LT 2000",AutoDesk

Related Posts:

AutoCAD Speed Test
Automated Drawing List Update Acad LT (revised)

Cold-Formed Steel Shed Industry: part:#1 (Shed Framing Drawings)
Cold-Formed Steel Shed Industry: part:#2 (Shed Framing Drawings)

Sunday, October 09, 2011

On Education, Industrial Awards, and Mobility of Professionals

I don't know but it appears that the modern world is highly focused on collecting credentials rather than actually doing work. Given a shortage of work probably not too much of a problem. Yes, I know there is apparently a global shortage of engineers, and also locally a national shortage of engineers in Australia.

But I have to question that shortage, the Engineers Australia linkedIN group has a variety of discussions taking place relative to the problems of overseas people getting their degrees accredited by Engineers Australia (IEAust). Not sure why they need to do this. But then the WFEO accords and consequent mutual recognition agreements, such as the Washington accord, the Sydney accord and the Dublin accord only really relate to qualified technical professionals. To become a qualified technical professional, the degree, only provides the enabling competence as IEAust puts it. Then depending on local requirements have to obtain anywhere from 3 to 10 years experience before can achieve, registration, license or charter. This may involve writing a collection of career episode reports, and combining into a work practice report, taking a professional interview, presenting a portfolio of work, sitting additional exam's (eg. FE/PE exams or IStructE part 3 exam etc...). If achieve the local requirements for full professional status, and that meets requirements of the WFEO accords, then mutual recognition holds and have the potential for mobility between countries.

However recognition of qualifications alone, doesn't mean going to get a job overseas, there are immigration issues, need to speak the language, and local experience requirements.

Those that finally have got accreditation of their degrees are apparently having trouble with local experience. Though I doubt the local experience is really the problem. Most jobs advertised require some 5 to 10 years experience: these are not jobs for graduate engineers. People who need accreditation of their degree are clearly not qualified engineers. The global shortage of engineers is not for graduates, for that matter it is not really for engineers. The real shortage is for highly experienced and competent persons with respect to established technologies, and highly innovative people with respect to unresolved problems.

Professional engineers, within engineering organisations governing the profession, having designed and defined an engineering team, have failed to educate practicing professional engineers about the differences in the membership of the team, and consequently professional engineers are failing to give the other members of the team the opportunity to put their education to work.

Part of the problem resides in past shortages of work, resulting in inflation of qualifications: thus a job that was previously the domain of an engineering associate has been raised to that of an engineer: the work complexity has not increased, and the person with a B.Eng in such job is never going to get experience required to achieve professional status: but since they can call themselves an engineer in anycase, what do they care about professional status? The problem however is that it produces an incorrect count of the necessity for engineers.

Up until the recent introduction of Federal industrial awards, in South Australia (SA), we had an award for draughtsmen and technical officers. This award covered drafters, engineering technicians, and engineeing associates. All 3 of these groups likely to have had a formal education of 2 years duration, so the duration of the education is not relevant to competency and capability. The Australian Qualification Framework (AQF) is based on competency and level of responsibility, not duration, though recently some guide line durations have been introduced. Basically AQF-6 (Associate Degree) upwards are university based qualifications, and AQF-6(Advanced Diploma) downwards are TAFE qualifications.

Apparently, the IEAust wasn't happy that engineering technologists and engineers were both AQF-7, since both have bachelor degree. So IEAust apparently responsible for honors degree AQF-8 being included, though 4 year professional degrees lost honors status some time back. It is also nonsense. Architects typically have a 5 year degree or 2 x 3 year degrees: the typical programme a 3 year degree in architectural studies, followed by time in practice, then return for the professional 3 year degree in architecture. There are other professions which comprise of a 2 stage study programme, resulting in 2 degrees. It should also be noted that from an industry employment viewpoint, not everyone goes onto to complete the 2nd stage and get the 2nd degree: it has no relevance to their employment.

That is part of the problem, professions have little relevance to the needs of industry and society, professional organisations are in some ways attempting to resurrect the restrictive practices of the old guilds. Science however is held partially responsible for the decline of guilds, along with national legislation and regulations. For example building codes specify requirements for buildings, whether prescriptive or perfromance based, the knowledge becomes public, and secret knowledge held inside guilds no longer acceptable: it has to become disclosed. Structural mechanics provides a disclosed method of validating adequacy of a building structure: so some secret ritual to appease the gods so that a building doesn't fall down, ceases to be accepted. Consequently mechanics institutes teaching artisans technical science, starts becoming alot more acceptable than the secret knowledge held by the guilds, and people outside the guilds start practicing and supplying more acceptable product than that supplied by the guilds. Some guilds cease to exist, others adopt the new learning, and become the examining and qualifying authorities. But still, whether guild, professional association, society, institution or union, there is some unwarranted restriction of practice already in place, or attempts are made to put such restrictions in place. Sure protection of the public is usually raised as the basis of the restriction, but that is generally misleading and invalid. The public is typically protected by regulatory and approval systems, with requirements for independent checks. Where licensing and restrictive practice is in place it is typically a relatively old practice and there is no conclusive evidence that such restrictions actually provide protection to the public. Arguments can tend to be presented either way, I favour arguments against licensing. Licensing tends to lead to self-certification, and code of ethics or not, tends to lead some approving things not in the public interest. Licensing tends to lead to monoply, escalation of prices and deliberate shortage of supply. Shortage of supply is achieved by making it difficult to enter the profession, and basing membership on requirements irrelevant to the task performed. Modern laws which protect economic competition, oppose granting monopolies to professions.

Having high standards to join a profession, is not opposed, having high ideals makes wanting to join the profession challenging and worthwhile. The objection is the shortage of supply. Requiring a building designed by a professional structural engineer is unacceptable, because it would tend to lead to restricted supply of buildings: when there are others who can carry out the design. For example engineering associates are capable of structural analysis and design, whilst the use of something like AS1684 timber framing code vastly simplifies the specification of timber framed houses which are structurally adequate. A engineering associate however is not likely to design a multistory building in a high seismic zone, or a bridge other than a short span foot bridge: they may however be involved in designing component parts or subsystems of such larger systems.

Universities and computers however have changed the nature of the workforce, engineering and otherwise. Traditionally designer-detailers would have done detailed design calculations, whilst the engineer concerned themselves with the analysis of the over all system. So for example whilst the engineer is calculating the bending moments in the individual elements of a multi-storey building, a design-detailer could be calculating stresses in beams already analysed and sizing concrete beams and determining reinforcement and producing the drawings specifying such requirements. The designer-detailer likley to have started career as a tracer, and moved onto drafter, and taken additional studies in the required technical sciences: their traing largely on the job working on real projects. The role of designer-detailer may be considered as a career for life, or a stepping stone towards becoming engineer. If no future positions for engineer in a company, then designer-detailer likely to be career for life, unless there is an opportunity to become engineer elsewhere. With more people going from school to university, the designer-detailer role displaced by graduate engineers. The role of engineer then becomes confused as does gaining the experience to become a fully fledged member of the profession.

The organisation becomes increasingly dysfunctional as more and more personnel become inexperienced graduates: both drafters and engineers. Many of the local South Australian consultancy businesses are like this. The "recession we had to have", resulted in shutdown of government departments and privatisation, along with lay offs from large businesses, almost over night there was a massive increase in consulting engineers, as those laid off set up sole proprietorships. Having established businesses these experienced engineers have no desire to show any loyalty to big business only to be laid off again, some do however provide services to the bigger consultancies on a contract basis. So some of the so called shortage of engineers is more a desire to have the experience back in-house at a lower cost. Whilst the IEAust is assisting with its graduate development programmes, and supply of mentors possibly external to a graduates employer organisation, there is still a lack of succession planning to sustain the technical workforce. That is largely because most of the effort is focused on the B.Eng and engineers is what we need: which is not so.

So first we have problem of professions defining idealistic requirements independent of industry needs, then a problem of educational institutions, universities and otherwise defining academic study programmes equally independent of industry needs, and a further problem of computer software and other technologies changing the industrial environment.

Technology has diminished calculation effort, first logarithms, then slide rules based on, then calculating machines, electronic calculators and finally digital computers. Engineer, structural analyst and stress analyst are different professions. The traditional engineer was more concerned with design, and supervising the implementation of such design. Engineering education in the 20th century however, shifted engineers into the role of structural/stress analyst and away from their traditional role. Hence the emergence of the problem of things being designed which cannot be built: a loss of understanding of their core function. The use of computer software is said to assist in a return to the core function. Computers can complete calculations in seconds, therefore don't need such a large team of people to assist in completing such calculations., and skill development doesn't have to be as focused on arithmetic or evaluating mathematical formulations. The problem is defining a new age profession whilst retaining past competencies, which are actually recently developed competencies anyway. The other problem is that other professions and occupations have arisen to take up those tasks engineers discarded as they moved away from their traditional role.

The environment is dynamic, and roles in industry are constantly changing. It is partly because of changing roles that occupational groups or professions are designed and defined by those dealing with the industrial relations system and the associated industrial awards. For example the metal industry had a multitude of job definitions and associated restrictive work practices. If I recollect correctly from my studies of industrial relations in the early 1990's, it was considered an achievement that some 109 jobs were reduced to some 63. I never saw the awards at the time, but the most recent I've seen there were 14 occupational wage levels: C14 to C1. Where C14 is a production worker with a few weeks of on the job training, and C1 is professional scientist or professional engineer. Though there were separate industrial awards for scientists, another for engineers, and still another for draughtsmen and technical officers. I say were because we are currently in a transition of moving towards more federal awards rather than state awards. Though national organisations like APESMA would have tended to make state awards for engineers similar. Anycase now have a federal award for technical professionals, and it covers scientists, engineers and information technologists.

Part of the drive for this rationalisation and grouping is to increase mobility in industry, and reduce industrial disputes. For example a weld slag chipper may have been prevented from sweeping the floor. On the one hand this protected the job of the person who swept the floor, on the other it was unproductive. Additionally it creates unwarranted ranking of job roles: neither chipping weld slag or sweeping floors is something to make a life long career out off, though some may wish to. Sweeping the floor in a hazardous industrial environment may require some training, but not necessarily less or more than chipping weld slag. The rationalised awards rank a multitude of such similar jobs into appropriate wage groups. The next issue then becomes developing a multiskilled workforce, which then leads to defining new occupational groups. From which then emerges qualification frameworks like the Australian Qualification Framework (AQF). Given that industrial awards and occupational classification tend to be based on formal education, it is likely that further simplification will result in one industrial award based on minimum wages for each of the 10 levels of the AQF. One of the things the AQF does is define core knowledge for various occupational groups, with electives. So having obtained core knowledge and graduated completing one set off electives, it doesn't require too much effort at some future date to take other electives to move over to another job function. The purpose of the AQF is to enable articulation from one occupation to another giving proper recognition to prior learning (RPL) whether obtained through formal education, on the job training, or self-learning. So building a portfolio of work as evidence of learning is an important aspect of obtaining an AQF certificate.

To move people from wage level C14 to qualified tradesperson at level C10, requires defining a skill set for an occupational group, which enables them to move between a multitude of job roles and job functions. Naming such occupations is also problematic. The change in materials and the change in technologies used changes many job functions and skill sets. A carpenter traditionally worked with wood, but when it comes to building construction likely to also work with steel and variety of other materials. They cannot be called builders because builders already defined and builders don't actually build anything but rather supervise building works. They cannot be called technicians because that is a more knowledge oriented activity than trade activity. Job titles consequently either remain and change meaning to reflect new role. Or in the main job titles just become meaningless and pointless, since they poorly describe the real skill set that the individual has. Individuals have similar problems to business in explaining to the public the services they can provide. Even within a business enterprise which chooses own internal job titles, the actual roles of various individuals may be distorted by the job titles assigned. Businesses restructure every so often, and assign different roles and job titles to better reflect internal operations: but it can still misrepresent real roles and responsibilities.

As I was saying computer software reduces the size of the engineering team required to complete calculations in a given time frame. So whilst an engineer could do the structural analysis whilst a designer-detailer designed members to the materials codes and worked on drawings, and this was carried out in parallel once the analysis under way: such work break down (WBD) between people no longer required. For structural analysis software can now rapidly carry out the analysis and size all the members, and increasingly generate the technical drawings aswell. So designer-detailers not required, and nor enitirely are drafters.

With the introduction of CAD many drafters replaced by CAD operators. The CAD operators only have a few weeks training in the use of CAD and have poor knowledge of a technical discipline: such as structural, mechanical or electrical etc...They also have poor knowledge of CAD. Increased training produces CAD technicians who have extensive knowledge of CAD but still poor technical knowledge. This adds to the dysfunction of engineering business organisations.

As the software becomes more complex with increasing integration of documentation and engineering assessment, there are calls to have more engineers use the software, rather than CAD technicians. But software is a specific tool and requires trained specialist for each software package. Such training not considered appropriate for engineers who should know the science behind the software. So there are emerging issues as to who should be building such virtual models and who should be responsible for them.

The other problem is an increasing dependence on such software. In many instances the use of the 3D virtual models is inappropriate and unjustified: it takes far too long to build the models and adds no value. But with diminishing skill sets concerned with more generic tools, there is inceasing dependence on such tools, and so increasingly inefficient tackling of projects with unwarranted delays. The real thing could have been built whilst they were playing with the 3D model. Task becoming increasingly more like a video game than real design.

I recently read somewhere a proposal for a 3 year bachelor degree in virtual modelling. I don't see the value in such things. All the time the solution to everything  is an high level academic degree. Such does not have anything to do with the task at hand, it is only concerned with status. Attract people by defining a degree, an AQF-7 qualification, and slotting people in at wage level C1, thus bypassing C14 to C2, and no where to go.

By rights moving from AQF-1 to AQF-10 should reflect increased depth of knowledge and increased responsibility level. Most professional degrees reflect breadth, not depth of knowledge. Also continuing professional development (CPD) requirements are seen by many as a grab for money, especially when weighting is used to diminish value of on the job learning and self-learning: and biased towards paid seminars and otherwise gaining higher academic awards. If actually practising engineering then always learning on the job. If not then probably operating at a level below engineer, on highly routine stuff.

It is this situation of persons not operating at the level of their academic award that needs to be resolved in industry. Persons with B.Eng set out to become professional engineers, cannot achieve and ignore profession. When the first required stepping stone should be to become engineering technician, no choice in the matter, that is where all start. If their job is at an advanced level, then shouldn't be too difficult to advance through technician, associate, technologist and finally achieve engineer status in a short time. For those with relatively simple jobs, they will get stuck at a lower level. But it is now clearer that they need to move on to another company to achieve full status as an engineer, or they need an external mentor to assist in putting their knowledge to use as an engineer and providing more value to their employer and raising their job function.

Another part part of the issue, is that people with an interest in design get stuck on engineering programs, which don't really provide for their interests, and 4 years is a long time. This can be achieved by proper articulation through the AQF levels from AQF-1 to AQF-9, with more industrial experience imposed between each level. So complete first year of B.Eng get AQF-5, complete 2nd year get AQF-6, and complete 3rd year get AQF-7 etc...But before get AQF-5, also have to complete AQF-1 to AQF-4. There then becomes a common core knowledge throughout the industry which all participants are aware of. For example everyone in the industry from trades people upwards can read technical drawings and specifications, and understands them.

Part of the current problem in industry is that occupations are now defined by educational institutions, rather than by industry. When defined by industry people progressed up through various positions in a business or stayed where they were. Those that progressed were aware of the skills of those below because thats where they came from. But with the education system controlling qualifications, people are coming from all over the place and slotted anywhere into the business organisation. So no one really knows the capabilities of their subordinates, and become surprised when the subordinate cannot do what is considered to be a common sense task. Problem is common sense is not common, it is environment and culture specific. School leavers have not spent long enough in the required industrial environment. If they have to get AQF-1, spend time in industry gain some experience and return to study for AQF-2, then a better understanding will be developed of an industry and its processes.

The training of an engineer, thus follows the more traditional route, from tracer, copy-drafter, drafter, design-drafter, to designer. From designer an increasing knowledge of scientific principles becomes necessary depending on the technology involved with. There are also issues of planning, supervision and management to consider, but these are really separate strands of study. Which is the reason to pay more attention to the AQF, than to professions. As a person goes in and out of industry moving from AQF-1 upwards, they will increasing reach a situation where they are offered a fulltime job, and otherwise given guidance to electives to study directions to take. In the main only qualitative understanding of science is required, followed by knowledge of established technology and supervisory skills. Rather than pushing towards AQF-9, better to have multiple AQF-6 qualifications. This not difficult because in the main will only require 1 year of fulltime study, or 2 years part-time, because the first year of such 2 year qualification will be a common core the earlier AQF-5 qualification. In other words a common core of broad technical science with diversions into more specialised areas. So for example not that difficult to cover civil, mechanical and electrical engineering, in 4 years, at the AQF-6 level. The current practice would be to define this as a B.Eng in some specific field such as say architectural engineering. I don't agree with such. For that matter I don't agree with the B.Eng in the first place: should have stayed with the 3 year B.Sc, with the applied technical fields being covered by additional awards such as graduate certificates. For that is part of the real problem, tradition put science into industry where it was applied and provided technical solutions. The B.Eng obscures what is added to the science as do many other professional degrees they should be scrapped, and get back to the B.Sc with something else to cover the applied practice. So an engineer for example more likely to have a B.A to cover the creative design, and a B.Sc to cover the scientific principles. But basic technical design only requires AQF-6 not AQF-8.

The idea is to get people interested, keep them interested, and have them progressing through qualifications from the very beginning. Don't want people leaving the industry, want them to find the right role and level. Some may have preference for planning and supervision so they get diverted to that quickly, others for design. Do not want to confuse industrial design and industrial management with engineering. Academic programmes for engineers are focused on the numbers, not design or management. I believe the young are being misled about what engineering is about. All the promotional programmes are biased towards building technology, not the engineering supposed to be promoting. From such progammes the school students should be taking up trade studies not engineering degree.

So really need to identify that which is unique to the engineer, and I mean in practice, not the foundational beliefs of those defining the profession and supposed subordinates. Engineering technicians, engineering associates and engineering technologists may work as subordinates to engineers, but all are more likely to work independently and subcontract work to engineers on an as needs basis. The actual operation of the industrial economic environment is complex, and we need to make far better of use of the available human resources. Not demanding that people spend increasing amounts of time in formal education before they can start to earn their own income. Got to get them into industry sooner, making use of acquired knowledge. Innovation occurs when people with a different knowledge base than those currently at the coal face are placed at the coal face. So cycle people between industry and formal education. The industrial revolution cascaded ahead because artisans studied technical science out of curiosity, either by reading or due to the availability of mechanics institutes and night schools. Rather than push a few to AQF-8, we should be ensuring that the minimum any employee has is AQF-6, anything less than AQF-6 and the person is still in a training and development programme. The first step however is to ensure everyone has an AQF-1 qualification, and in the main that requires providing evidence of prior learning. The primary step therefore is not going around teaching any one, but assessing them and recognising the learning that they already have.

Pricing Labour and/or Services

Prices are not absolute, they are only ever relative to a given point in time and set of circumstances, and therefore related costs are also relative. In Australia we have state and federal industrial awards which set minimum working conditions for various occupations, including minimum wages. These awards have embodied within them wage relativities which are typically sustained. It creates something of a new age aristocracy, with ranking being based on academic ranking and some groups perceived importance of the occupation. For an otherwise equitable society this is inappropriate. The flaw with such state or national ranking is that its says engineers for example are always worth more than tradespeople: such is nonsense.  Whilst people do get paid over the award rates and therefore there is scope for variability in the market, the occupational representatives will appeal to the industrial courts and commissions to have the relativities reinstated, that is adjust minimum wages in the awards to market rates to keep one occupation ranked higher than another. The nonsense with such scheme is that it is applied across industries and across the state and/or nation, when relativities should vary between businesses dependent on staff and line functions. An engineer in a consultancy has a line function and is more important to business operations than a carpenter who looks after the buildings. An engineer who works for a building company has a staff function and is less important than the carpenters who fullfill the line function. Staff can be terminated and contracted on an as needs basis, line personnel cannot be contracted on an as needs basis for they are the point and purpose of the organisation.

Giving consideration to a sole proprietor, if they contracted the line function, then effectively handing the work over to someone else who gets paid for the job, and so the  sole proprietor doesn't make anything except maybe a small commission for having the work to handover. However tend to get paid more for doing the work than simply attracting it and handing over to others, so if going to hand the work over to others to do, then need to find a lot more work to do. A modern trend in business is to do exactly that: find work and get others to do it. Some engineering consultancies for example have a small core of personnel, they tender for work, and once they have the contract they then seek out personnel who can actually do the work: that is they don't have the expertise nor the labour capacity in house. But this not really any different than other businesses, builders contract to build, but subcontract to drafters, engineers, carpenters, plumbers, electricians, concreter's: a sole proprietor builder with no personnel at all. So what price, what value the effort of those who distribute work, what commission should they be paid? Should there be an industrial award for such activity, and should there be an occupational title for those who carry out such activity? My feeling is no! The industrial awards whilst useful for new startups, otherwise tend to distort the market. It may be beneficial to set a minimum wage to impose a minimum standard of living, but even that is questionable.

Some 95% of all businesses are small business, and account for some 48% of employment: small business employs less than 20 people in non-manufacturing and less than 100 in manufacturing. Some 80% of Architects, Surveyors and Engineers practices are very small business employing less than 5 people. Whilst industrial awards are imposed on employers, they are not imposed on sole proprietors: some industries are dominated by sole practitioner businesses. There are many activities where by individuals consider that they get a greater share of the potential income if they work for themselves rather than as an employee. For whilst it is possible to be paid over the award rates as an employee, something has to happen in the market place before that will happen. Changes in the market may only affect a few businesses and/or employees. If the market does not provide the desired increase in wages for employees then pressure is applied to bring about changes to the awards. This can impose on all businesses to increase wages even though the individual business has experienced no increase in sales or increase in productivity. Potential exists for big business and/or their employees to manipulate the system to grab a greater share of the market, at the same time as award wages are increased beyond capacity of small employers. Small employers tend to retract to being sole practitioners again. Sole practitioners are not bound by industrial awards, only need to cover cost of living.

For a business enterprise, sole proprietor or otherwise, income is what ever they are able to get, there is no industrial award which sets minimum income levels. The industrial awards however do provide a basis for minimum costs to be covered by the income. Business however is a real world experiment, and just because industrial awards set minimum wages for employees, it does not mean that the business is capable of recovering such costs from its sales and operations. The sales which can be achieved at any point in time are uncertain, therefore total income generated is uncertain. Possibly more importantly is that not all costs are visible, tangible, measurable and allocatable. It is a matter of emergence or synergy: the whole is different than the sum of the parts. For example calculate the visibile costs, release a product to market and it only sells for less than the sum of costs. Release another product to market and it sells for significantly more than the sum of costs. Labour, mind and body, is no different than any other product: it can be bought and sold for what ever price the market is willing to support. Sole practitioners don't allow the industrial aristocracy dictate wages to them, they leave it to the market place to determine their income. For some who quit their stable jobs in hopes of making more money than the industrial awards grant them, this may be a bad move. For those who lost their jobs because of changes in the economy, "recessions we had to have", then owner/operator of a small business may represent income not otherwise available: less than the award but more than unemployment benefits. Cities may represent a different kind of environment than our ancient hunter/gatherer ancestors, but it is still a wilderness and a we are still fighting for survival. Cities, and modern technologies do not gaurantee comfort and luxuries, no matter how hard you work. Further more hard work does not give right to such things.

The basic guide for pricing labour as a owner/operator, is to divide desired income by the number of hours expect to work. Desired income has to cover minimum cost of living to survive, but can otherwise reflect desired lifestyle. The expected hours of work, can reflect the available hours willing to work, having spent time on other activities.Hence it is beneficial if can get paid to do what you like to do, spending as many hours as are able to do so.

Labour rate = Desired Income / Expected Hours of Work  [$/hour]

This only represents the cost of owner/operators labour to a project, also have to cover costs, and determine chargeout rate. For contractors, with little expenses, the typical guidelines reduce the expected hours to account for such things as: public holidays, sick days, vacations, and long service leave. This calculation is some what important to full time employees on industrial awards: for they get paid for more hours than they actually work. For example consider award wage group C14, last I looked $522.15/week, for a 38 hour week, and a 52 week year. Therefore annual income $27,151.80, for total of 38x52=1976 hours per year, leading to hourly rate of $13.74. But allowing some 47 days at 7.6 hrs/day, paid without work, that removes 357 hours, leaves only 1618 hours actually worked. Thus have to recover the costs of labour at rate of  $16.78/hour labour charged out, before additional expenses are added.

How to cover the additional expenses if not easy to directly allocate, or would otherwise cost more to track than the effort is worth. The simplest approach is to take expenses as a proportion of total revenue and otherwise assume zero profit.

P = R - E
if P = 0 then R = E

E = L + OH
Let OH = fR therefore E = L + fR

Therefore : R = L + fR

R = L / (1-f)

Where P= Profit, R=Revenue, E=Expense, OH=Over Heads, L=Labour, f=OH/R

The fraction 'f' may be available in industry surveys, from historical sales data if business already operating, or otherwise some reasonable number adopted, that is guessed. For example if f=0.4, then: R = 1.67L., and so the $16.78/hr becomes $27.97/hr.

Having calculated a labour rate, by the preceding method it doesn't mean that going to get any work. The hours for a project multiplied by the labour rate may produce a price that the market doesn't like: and note the potential customers in the market are not caluclating costs, they are just guessing or have a gut feeling about what they believe to be a fair and reasonable price. If the customer can do this, then so also can the supplier, at the end of the day the price is what both buyer and seller are willing to accept.

"The successful producer of an article sells it for more than it cost him to make, and that's profit. But the customer buys it only because it is worth more to him than he pays for it, and that's his profit. No one can long make a profit producing anything unless the customer makes a profit using it. " [Samuel B. Pettengill]

In the building industry many businesses over value what they sell, from builders, to manufacturers, to designers and engineers. There contribution to a project is low value and unimportant. Many engineers would find themselves unemployed if regulations which imposed their presence was removed. You don't pay an engineer $1000 to remove and save $1000 worth of concrete, better to have the resistance of the concrete than some scribble that says not required. Too many engineers seem to make the mistake that they protect public safety and stuff would be hazardous without an engineers presence: not so. They neither impart real cost savings nor achieve safety. The issue is that the safe economical system has already been provided by heritage, and therefore current batch of engineers contributing little. Part of the problem is the wage relativity nonsense of the industrial awards: choosing to be an engineer because expect to get paid more than trades person. Engineers are being produced because we can produce them, just like we can produce cars we don't need. Having produced them have to make up reasons to need them, to sell them, or create legislation to impose them. Having a degree does not give a person a right to a high salary, nor to public recognition. Far too many modern professional engineers are relying far too much on the contributions of ancestors to conclude the value and importance of engineers. Those ancestors however do not however have the skills to match the modern specification of professional engineer nor did they have the same attitude. Business requires that can generate revenue, society requires that contribute benefit. To gain recognition modern professionals who want the recognition have to do the contributing. Much of the technology provided is not all that important, and people since the dawn of industrial society have questioned its real value, and still question its value. The survival of populations in cities is dependent on water pumped into them: no power supply, then no operational pump and no water, and if no water then no people can be supported in the city. Finite resources consumed to support a growing population, with no real thought to the future. One possible future is population catastrophically wiped out as it runs out of power. Another possibility is that population will simply age and die out without replenishing itself, leaving a ghost city. The future is uncertain and business is trying to predict future income from todays actions. Rather than engineers complaining about their status, and their incomes, they should better understand the nature of business, the environment and uncertainty. Problem is too many engineers worked for the government in the past building infrastructure to herd the population: they consequently have something of a more dictatorial attitude towards the people and sense of own self importance. Such attitude not going to get them very far in the new modern world of privatisation. The businesses the engineers work for have to provide real value at the right time. The infrastructure that engineers provided whilst working for the government is not seen as a benefit by all: though the engineers see it as a benefit. In business, think you have a good idea then pursue at own expense, not the peoples expense. Then again, the business has to get the money for research, design and development from somewhere, and that somewhere is the customers who pay more than the cost of the product they buy. People don't so much object to profits, but to what the profits are used for. Profits used for expensive suites, expensive cars, expensive houses, holidays, world trips, expensive offices, and typically an expensive lifestyle are objected to most especially if the quality of the service provided is low.

So for example there is a lot of DIY because people can cost the materials, and have spare time in which they can do the work. Without getting into complications of comparitive labour rates and opportunity costs, the individuals simply perceive that the cost difference between supply price and material cost is too high, and therefore choose to DIY. So to get the work have to demonstrate the value in service supplied. Builders cannot get the work, drafters cannot get the work because of DIY, but engineering practitioners get the work because legislation imposes a need for calculations that most people cannot DIY. But cannot rely on such captive audience remaining: also having a captive audience diminishes the recognition get from such audience. It is therefore necessary to build real value, and demonstrate that value to potential customers. That is recognition from customers not the population.

Part of that added value is having the solution before the customer turns up. Things can be designed once and made many times, or if a service carried out many times. Car manufacturers build cars with features that the market hopefully wants. Whilst buildings are typically built to customer requirements, and are thus not available when the customer turns up. On the other hand established buildings dominate the available supply, but typically can only buy an established building if it is not in use. However there are market builders who have stock plans, the house isn't available when the customer shows up, but they do have a choice of designs to choose from. Design and engineering are additional costs, new buildings represent delays in supply, and they also have teething problems, all compared to an established building. An established building may however have problems that need resolving. The value of available supplies thus determines decisions made and directions taken. Such decisions are not necessarily taken using any direct costing, or cost-benefit or value-analysis. At the end of the day these are just sophisicated methods to justify a guess. Using such tools the parts maybe weighted and valued, but the sum of these parts doesn't represent the value of the whole. So the opinion relative to the whole is no worst nor better than that based on the sum of opinions relating to the parts. A guess is a guess no matter how sophisticated. In the modern world there are far too many mathematical models which are given unwarranted credence, and yet there is only garbage to feed into them and consequently only get garbage out off them.

Costing methods can be made increasingly complex as can pricing methods, but at the end of the day, acceptance in the market is left to personal opinion or subjective judgement. Business is an experiment, and getting the price right is part of that experiment. The business has to be dynamic, adaptive, and responsive to feedback from its operating environment.

Not suggesting avoid sophisticated costing and pricing methods, just that they have to be appropriate to the age and nature of a business activity. The older an activity, the mre likely all its associated costs can be determined including those intangibles such as allowance for future needs. Further it can be determined whether detailed tracking is required, and the level of detail required. Often tracking costs more than the benefit obtained.

Time Is Life, Time is Not Money!
One problem with the previous rate is that it gives rise to the believe that time is money, and the concept that some engineers have that they sell time. Hourly rates are problematic. Contractors are likely to drag a contract out so that they don't have to find another contract, and so get the most from one contract. One recommendation for calculating contract labour hire rate is to allow 20% loss of time looking for work. This gives rise to different recommended rates for short contracts and long term contracts. Lower hourly rates are charged for longer contracts. The acceptable labour rates determines how long can be spent looking for work, so that more than 20% may be possible: since also dependent on what it costs the individual whilst they look for work. Also don't have to look for work, can spend the time in other activities, such as developing solutions, so that have available when a customer turns up looking for. Got to change mindset away from the 9 to 5 work time mentality. The difference between working on the business, versus working in the business. Most people who give up their job and start a business, are still locked into the employee mentality: do the work that flows in and pay no attention to where it comes from or why? A few years later no work, no business and no income. Firefighters are paid to be on stand by, there can be no doing something else when on stand by, they have to be available for fighting fires. Part of being in business means being available, even if not doing any work, and so there is a cost associated with such availability. For example a cost of not doing any work this week, so that can start work next week: if choose to do work this week may have to spend many more weeks without work. Hourly rates therefore have to be increased to account for reduced hours actually working.

Another issue to consider with hourly rates is that not every hour worked is worth the same value. With extensive division of labour within an organisation lower value tasks are carried out by persons on lower pay rates. But even then not everything that these people do is worth the same value, however the average value of their work is less than the average value of someone elses typical work. By distributing work to a collection of people on different labour rates a lower over all fee for a job can be determined, compared to fee worked out on the basis of the cost of the top level skills required on the project. For example internal to an engineering consultancy an engineer gets paid more than a drafter, the bulk of the work tends to be drafting, and fees worked out with costs distributed between drafter and engineer. As sole practitioners however the fees of the engineer are too high, the work flows to the drafter who subcontracts the engineer on an as needs basis. Further more the engineer typically cannot relate well to the customer, so subcontracting to the drafter, is the wrong direction for the customer, even if preferred direction for the engineer. The engineer has to be doing the drafting work if to relate to the customer, and needs to be charging a lower fee for such work. Since such engineer is doing both drafting and engineering, their average rate is lower than those just doing engineering, but still higher than the drafter. The net fee however may still be too high, however there will be less delay compared to the engineer and drafter combination. So there is a premium for the faster delivery time.

Higher prices have either premiums or penalties incorporated. A premium because there is benefit to the customer, penalties because there is some disadvantage to the supplier. Higher prices do not mean higher value or increased quality. Prices are relative things.High prices may just mean that the supplier doesn't want to do the work. So having found someone who can supply at lower price is no loss or detriment to the supplier with the higher price: they achieved what they set out to do, not be hassled with such work. Its not always a race to drop fees and grab work. Often greater benefit in pushing fees up and pushing the work away, ultimately the price gets high enough that the work no longer seen as a hassle and the work is accepted.

Whilst a project fee may be worked out on the basis of an hourly rate and an estimated time duration to complete with possibly material costs included. The final fee is subject to the nature of the market and may need to be dropped, or it may be possible to increase it. It is not necessary to have calculated detail as to where the fee came from. It is only really necessary for the business to have an accumulative income which stays ahead of the accumulated expenses: not for the individual project. Some projects are a loss, others a gain, on average the business achieves a nett gain. There should be no drop in quality due to a loss on the project, the business still has the resources to do properly, the project is just not self funding, and there is no reason why all projects should be. The problem is owners who extract excessive profits from the business to fund exorbitant lifestyles. Profits have to be retained in the business to fund future uncertainties.

Projects which make a loss are indicating something about the market. Like we are tired of paying large fees to be told what we already know, so if such "service" must be imposed on us, please do so at lower fee. Which means figure out what is really required, what value it has and charge an appropriate fee for. When it comes to engineering there is a perception that it means supply calculations: which is a low quality service to provide. Relevant calculations can now be done by computer in a few seconds, a mere fraction of the time taken by engineers calculating by hand. Selling time thus becomes silly. Further it is what happens prior to and after the calculations that is important not the process of calculation itself, such calculation process is an hindrance and delay. These "fore" and "after" actions are where the value lies. So let other than engineers use the computer programs and play around with the models, it is better than them building the real things and having the real systems fail. They still need some one to validate and certify the final design and a fee to be charged for. The playing around with design concepts however is where it belongs in the hands of end-users and/or makers, getting familar with a concept and experimenting with its benefits and detriments, and otherwise checking the consequence of variations. Designers do not have to be qualified, they do not have to understand scientific laws, they can build prototypes and understand the real thing. If they can build computer based virtual prototypes then they can save time and possibly expense: they get to find out for themselves why some part of a proposal is a bad idea.

Point is things become established, and technologies change, so there is an expectation that supply prices change, and typically that means decrease. What engineers complaining about declining fees fail to understand is that the value of their contribution to projects has been steadily declining, as their output becomes more and more routine, predictable and expected because variants already exist in the technological environment. It may be possible to sell each car produced at similar price because each one takes similar effort to build. But this does not hold true for specifications of a car, or anything else. The first specifications take a great deal of time and effort to create, copying however is a considerably simpler and less time demanding activity. Even variants are less demanding than the original. Heritage diminishes value of future endeavours, it provides a foundation on which to build. So cannot expect to keep charging same price for design work. Experience both diminsihes and adds value. Experience adds value because know the answer now whilst someone else has to work it out. The cost of someone else working it out basically matches the cost of knowing the answer. But once all know the answer, the value starts to decline. So all this hourly rate, time is money, selling time stuff is misleading, as is having national industrial awards. Prices, labour rates, fees are all highly variable and uncertain. Start with something, anything, monitor feedback and then change accordingly. Small business, sole practitioners are typically better able to respond quickly to the market, than large businesses. Larger business more into controlling the market than responding to. There are no certain answers, just got to get good at experimenting and predicting the right response, the desired response from a complex system.