DXF For Laser Cutting Has Too Many Line Segments - Laser Head Shakes

[zac.portnoy]

Alright so, here's my issue that the company I work for has faced for quite some time. We take on these custom logo laser cutting jobs a lot. We have a 10' x 5' Mazak Fiber Laser. So these are often large jobs cutting steel. 

I am the engineer on staff so I prepare the artwork, often received as a PDF, into a DXF. I do this usually by auto-tracing the image in Inkscape or by manually drawing it in SolidWorks if the shape is too blurry or complicated. I then export that image as a DXF.

The problem is, if there is text or other objects that have arcs and such in them, they turn into hundreds, if not thousands, of tiny line segments. These can be cut on the laser, but it will rattle the head back and forth to trace the lines out. We do not want that. Now, I could go back and use the features in SolidWorks such as arc and spline and replace all of these and make it work. But, this takes hours of time that basically outweigh the profit we would gain from the job itself. I have been trying to use AutoCAD LT to turn the lines in splines, but selecting them all individually and converting them to polylines, then to splines, takes longer than just going back and drawing arcs for everything. 

There has to be a faster way. I am a novice in AutoCAD, so please be explicit in your descriptions. 

Thank you.

[pendean]

So you draw in other program(s), export to DXF, then try to fix it all in AutoCADLT? That's likely your issue right there. I bet if you visit those software's user forums you'll get tips on creating cutter-friendly dxf file right from inside those programs.

This tutorial/guide is perfect for everything you need to do in AutoCAD/LT https://wiki.mcneel.com/rhino/exporttolaser

AFAIK if I understood your need there is nothing in AutoCAD/LT will take a 100000 little lines to convert them into splines/plines then reduce the number of nodes automatically for you (which is what you are trying to do I suspect?).

[zac.portnoy]

The reason I am here is because I have already investigated how to do this in those other programs. Yes I draw it in Inkscape, because that's a program that has a good auto-trace feature. I export it from a DXF and then double check it in SolidWorks. SolidWorks allows me to extrude the 2-dimensional drawing to confirm that there are no gaps and that the design should cut well and not fall apart. There are no good solutions in either of those programs that I have found. So I'm trying to see if AutoCAD has a good solution. In other forums, I have found people who said they have fixed this exact problem in AutoCAD, so there is way from my understanding. 

[Dhananjai_Gopika]

From the original post:
"I have been trying to use AutoCAD LT to turn the lines in splines, but selecting them all individually and converting them to polylines, then to splines, takes longer than just going back and drawing arcs for everything."
I understand you are trying to prep the drawing by converting the lines to spline and are looking for a quick way to do it.

1. Select the lines efficiently using selection windows shift key etc. For good practices refer: https://www.cadtobim.com/object-selection.html
2. Use the Join command after selecting it.
3. Convert the resulting polyline into a spline (PEDIT -> Spline)
   

If your requirement is to reduce the vertices, please note there is no dedicated command in AutoCAD LT to simplify such complex polylines. On AutoCAD Map 3D and Civil 3D, a dedicated function is available. See: About Weed Polylines.

You can refer to the following article to know more about it.

• How to simplify polylines with a large number of vertices in AutoCAD

[wanissboucettapro]

This is exactly the workflow problem I dealt with for years. The issue is that you're going PDF → Inkscape auto-trace → DXF, which is why you're getting segments — Inkscape approximates curves with polylines instead of real arcs.

If the customer PDFs are vector files (exported from Illustrator, CorelDRAW etc, not scanned), you can skip Inkscape entirely. I built a tool that converts vector PDFs directly to DXF with real arc entities — no segments, no manual cleanup. It's free to try: pdf2laser.com

If you're not sure whether the PDFs are vector or raster, zoom in close in a PDF viewer — if the edges stay sharp at any zoom level, it's vector and the direct conversion will work.