Designers working in disciplines such as architecture, landscape architecture and mapping are often on the receiving end of AutoCAD or IntelliCAD drawings that have passed through several hands before reaching them. Typically surveying firms, civil engineering firms etc have completed their own design work with very little thought given to the requirements of subsequent users of their drawing files. This process often causes problems for others working 'down the track'. 

This set of notes is designed to provide some guidance on the handling of incoming drawings so that your own design work can proceed as smoothly as possible.

Print this page off and use the check boxes □ on each new job.

Run a virus check on the file

Do not rely on the sender making sure that the file is free from viruses. Run your own check. □  

Copy the drawing to a special folder

Once the drawing has been received (either by email or on disk) We recommend copying the drawing to a named folder. We typically call the folder 'Incoming' and save it as a folder under the job name. An example is given below:

Do not alter this drawing, keep it as a record of what you have received from the previous designer in the 'chain'.

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Copy the drawing to your working directory (folder)

Now copy the drawing into your working folder. I like to rename the file at this stage and give the file a prefix using the date at which I start to modify the drawing. In the example below the drawing is now called 08_03_01 planting.

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Now get a 'feel' for the 'foreign' drawing before you begin to work

In no particular order of importance, carry out the following:

• Start AutoCAD or IntelliCAD. Open your 'renamed' drawing. Watch carefully as the drawing loads and jot down any error messages that appear. The most common message will involve missing fonts and missing external references. The F2 key can be used to 'pop up' the text window and you can carefully scroll back and sift through any error messages that appear. Both AutoCAD and IntelliCAD will substitute one of their own in-built fonts for a missing font, so you will not lose information. However, substituted fonts may 'bleed' into unwanted areas in the drawing and look very untidy. If fonts are missing, ask the originator of the drawing to send copies of the missing fonts and put them where AutoCAD and IntelliCAD can find them - on the search path. 

• Run the AUDIT command. Allow the program to automatically fix any errors that may be in the drawing.□

• Turn the UCSICON on. This helps in determining the 'space' that has been used for the drawing.□

• Switch to model space, zoom extents  and use the VPOINT command with 1,1,1 and check to see if their is any 3D information in the drawing. Type PLAN to get back to the top view. □

• Watch the DVIEW option. Make sure that the UCSICON is on in model space. In the example below, the designer had used the DVIEW command to twist the view such that the main road was in the vertical plane (left panel). The DVIEW command is normally used to apply perspective, so this took a considerable amount of detective work to establish this. □

• Some designers send a copy of their 'pet' menu with their drawing. Make sure that the correct menu has been loaded. The MENULOAD command is useful here. 

• Zoom, Extents (to see the whole design) and then Zoom in on an object in the drawing of known size. Use the DISTance command to measure the object. This will enable you to asses the units that have been used to build the drawing. In the drawing below, I was able to determine that the designer was using meters as the base unit. The SCALE command was then used to scale the entire drawing by 1000 so that I could work in millimeters.□

• Check the layers being used, paying particular attention to any layers that may be frozen. Thaw (all) to reveal everything and then undo back to the 'as delivered' state. In this way you ensure that you know about all entities in the drawing and that the previous worker has not left an important layer frozen. The figure below shows that in our test drawing, a number of layers were indeed frozen.□

• Some versions of AutoCAD and IntelliCAD have tools variously called layer managers. Save the state of layers as you first open the drawing as 'as received'. You can then return to this state during the detective stage if required.□

• Create a series of layers for your new work. If for example, you were a landscape architect working to the US AIA standard, you might make a layer called L-PLNT-TREE for new trees, a layer L-PLNT-TXST for existing trees and so on.□

• Zoom extents and use the limits command. □

• Use the ID command to obtain the coordinates of a point in the drawing. the bottom left may not be 0,0 which you are used to. Set up the limits correctly so that your grid and snap will work properly.□

• Turn on the grid make sure that the designer has not used SNAP and rotate to alter the angle of the grid.  □

• Use the BLOCK command with the ? option and get a list of blocks used in the drawing.□

• LIST several entities in order to determine the 'space' they have been drawn in - model space or paper space. It is highly likely that some blocks may need to be exploded. Watch out though for attributes store with blocks. Exploding a block will destroy the values contained in a block. Switch to paper space to check if entities have been drawn in paper space. □

• Use the PURGE command to remove any unwanted entities - layers, linetypes, blocks etc. The ALL option can be useful. Remember to save the drawing after this, then close it and reopen using the purge command again because a single purge does not get rid of all unwanted blocks.□

• Use the ATTDISP command to set ON. This ensures that all attributes stored in the drawing are displayed. □

• Use the VIEW command and apply the ? option to determine any views stored with the drawing. Similarly LINETYPE and ?, Dimension and ?, STYLE and ?, XREF and ?, Layer and ?□

• List several entities in the drawing of different colour determine if colour has been set BYLAYER or BYENTITY.□

Now you are ready to create a new drawing. I recommend using the XREF command to attach this drawing (the one that we have examined in detail) as a base plan.

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