igs flat pattern to .dxf format 1

[sam413]

I'm searching for a procedure in Catia v5 to output a .dxf file from a .igs. Basically the .igs is a flat pattern laser template that I need to save as .dxf so i can process it through a laser programming software. Any help or advice would be greatly appreciated.

Sam

 

[DBezaire]

Sam
Rename the .igs to .ig2 -- this will load it into drafting. Now you can use Save As - .dxf.

Regards,
Derek

 

[sam413]

Derek, Thank you so much for the tip. Maybe you can help me with a similar issue. I'm a CNC programmer and dont use Catia for anything other than file conversions. The problem I have been having is with .dxf models I receive from my customer that were made in Catia. When i read then into my software the lines often come in segmented and not tangent which causes the laser processing software to error out. Can you suggest why the .dxf from Catia come in this way. It is my understanding that the designers "pull" the 2d drawings from 3d solids in catia and even they admit that this process often produces non tangent lines especially where arcs meet line segments. I realize this a "laymens terms" explaination but hopefully you get the idea.

Thanks again,

Sam

 

[DBezaire]

Sam,
I feel your pain. Must you use .dxf for your laser or could you use lines,arcs, splines from 3D projected flat on a plane? I do this for a water jet source.
Sometimes the gap will exist in the 3D solid. There is a merging tolerance in the Generative Shape Design (GSD) module, be default up to .0039". The merging tolerance is forgiveness but it will not correct the gap and will be noticed after file translations and/or disassembly. Can you get the native Catia drawing file?

Regards,
Derek

 

[sam413]

Derek,
The software I use prefers .dxf format. I can get the native Catia drawing file but in the past it hasn't helped much. In the past I have "fixed" the gaps between lines and arcs with my programming software but this can be time consuming be cause of the nature and amount of templates I process. I have had a bit of sucess with a different procedure using your tip of changing the name of the .igs file. I directed the designer to create the 3d wireframe and simply write it out as a .igs, then change the extension and re-read it back in to catia and save as a .dxf. This had the effect of eliminating the gaps and non-tangent lines and arcs (at least on the 1st 2 test pieces) I'm hopeful this procedure will smooth out the problems I've had with the models.

Thanks again for your inciteful comments and tips

Sam

 

[Azrael]

Regarding the line gap issue in the dxf format when used for laser cutting, I have a setting that may help, it's not fool proof though. This enviromental variable will change how the arc is defined when exporting to dxf.

DXF_ARC_EXPORT=2

 

[PeterGuy]

I have delt with this issue by creating a macro that extracted the surface from the flat. Created a boundary of the surface. Rotated the curve so it had a sensible orientation. Coppied the resulting curve to a new part. Projected the curve in to a new drawing, then exported the drawing as dxf. A bit convoluted I know but it works and is a single click solution. The only caveat is that the option to project surfaces an wireframe into drawings must be set manually before hand.

 

[belvedere64]

For a DXF water-jet, I have projected the 3D flat pattern in a drawing with success. this may be quicker than cleanup in your laser software. I like PeterGuy's method extracting a boundary first: more control and more robust math behind the geometry. It might be worth your time to learn these, then learn to script it.

/k.c.takacs

 

[sam413]

Thanks to everybody for all the great tips. In the end our solution was to switch to a software that didn't exhibit the symptoms that Fabriwin had. Tebis proved to be a much more forgiving software for processing not only the laser programs but all cnc programs.

Thanks again

Sam