Writing plot data to a CAM file - AutoCad 2000

[Stanier]

Hi - I am experimenting with a simple form of CAD/CAM and would like to be able to export the coordinates of my drawing to a data file in order to use it as an input file forthe CAM system. I am running AutoCad 2000 and would expect to be able to have this option available under the Plot command but have not been able to see how it can be done. For example, taking the simple case of a rectangle, I would like to be able to write to file the coordinates of the four corners of the drawing.

Can anyhelp tell me how this may be done. Kind regards.

[MSasu]

On that version you should either (1) save the files in DXF format, open the file, look for ENTITIES section and get the coordinated from there or (2) use an AutoLISP routine.

[Stanier]

Hi MSasu- Thanks for the quick reply. I have been able to create the .DXF file but can find no reference to ENTITIES. Where might I find this in AutoCad2000?

Kind regards

[eldon]

Open the DXF file in a text editor, and do a search for ENTITIES.

[Tyke]

It is possible using one of the programming languages available in AutoCAD to export the coordinates and other information of all the entities in a drawing to a text file.

 

Have a look on Lee Mac' website where you will find a wealth of good information to get you going with LISP and a large selection of good LISP routines. Here's the link: http://www.lee-mac.com/index.html

[Stanier]

Hi - Apologies for the delay in replying but many thanks to those who have replied to my query. I now hope to be able to make some progress.

[Stanier]

Hi - Following up on the thread above I have now been able to save my Autocad drawing in .DXF format and have now opened it in Notepad to find the string "ENTITIES" from which I was able to recognise some dimensional data associated with the drawing. Can anyone iexplain in simplfied terms the next step in creating a CAM control file i.e. how to separate out the relevant dimensional data from the mass of information available in the file. Ideally I would like to be able to limit the data to be extracted to that contained on one particular level e.g. that level in which I have put all the relevant dimensional data. Can data associated with specific levels be indentified in the .DXF file? Apologies if the questions might appear to be somewhat naive. Kind regards

[eldon]

Perhaps when you create the DXF file, you could use the option of Entities Only. That way, you could select the entities that you are interested in, and leave out the rest of the abundant data.

 

I have no experience in CAM control file, so cannot help you with that.

[ReMark]

Stainer: How often are you going to be doing this sort of thing? Have you heard of a program called MeshCAM?

[Stanier]

Hi - I must confess to only dabbling in CAM but some years ago before having use of AutoCad 2000 I used the drawing package DraftChoice which although not as sophisticated as AutoCad did all the basic things and enabled dimensional data to be exported in the form PAnnn (Plot Absolute). When copied and pasted into Notepad the data could be modified if required to PRnnn (Plot Relative) and run with a simplyfied CAM package which recognised these and other basic pen commands. Pen (i.e. cutter) movements were assigned by the commands CDnnn (cutter down) and CUnnn (cutter up) where nnn is the required dimensional movement expressed in thousands of an inch. My plan is to copy/paste the data extracted from the .DXF file in a similiar way and modify it to apply the required cutter movements. At least, that is the theory.