openSCAD Centering Ring Generator

[Winston]

I finally discovered online a simple trick to use openSCAD to generate DXF files for laser cutting, something I've long wanted to do. I don't have continuous access to a laser cutter, so I'd appreciate it if someone who does would either cut the included example DXF file or make one for their own specific purpose and cut it on their laser.

If this DXF file works well when actually tested on a laser cutter, the same openSCAD STL-to-DXF conversion trick could be used on the products of an openSCAD program written to create fin outlines for laser cutting.

View attachment OpenSCAD centering ring generator.zip

 

[martinjaymckee]

I didn't know you could do that with OpenSCAD! It's probably my favorite way to construct 3D geometry for 3D printing, but that's a neat trick to get 2D geometry with the same parametric-design advantages.

I don't have immediate access to a laser cutter either, but I'm planning on cutting some things later this week anyhow, so I'll give the demo file a run. What I did do is to run it through the laser control software ( which I have on my computer ), and the file looked perfect. There were no alignment issues, breaks, or other artifacts, so I expect that the DXF is perfectly formatted ( the software is buggy, actually, so any file that isn't perfect doesn't import properly ).

Martin Jay McKee

 

[Winston]

I didn't know you could do that with OpenSCAD! It's probably my favorite way to construct 3D geometry for 3D printing, but that's a neat trick to get 2D geometry with the same parametric-design advantages.

I don't have immediate access to a laser cutter either, but I'm planning on cutting some things later this week anyhow, so I'll give the demo file a run. What I did do is to run it through the laser control software ( which I have on my computer ), and the file looked perfect. There were no alignment issues, breaks, or other artifacts, so I expect that the DXF is perfectly formatted ( the software is buggy, actually, so any file that isn't perfect doesn't import properly ).

Martin Jay McKee

I didn't either, but I've been looking forever for some way to get 2D files from openSCAD since it's the perfect CAD app to create things like centering rings and fin outlines simply by manually inputting into an openSCAD script the fin design data from OpenRocket or Rocksim (the latter being a script I haven't written yet and might not be writing for a while - if anyone else wants to write it, definitely be my guest). I do not know how I managed to miss this trick method to get a 2D file from openSCAD in previous searches, but I finally found it, thankfully! I must have finally been using just the right Google search words. I've found STL to DXF and SVG conversion paths before, but they were not available in free software. Maybe I missed something, but we don't need it now since we have this dirt simple method using just the freeware openSCAD.

Thanks for trying it out once you get access to a laser cutter. I don't know how long it'll be before I have access to one.

If others require SVGs for their laser cutter software as some apparently do, here's a quick and simple on-line DXF to SVG converter:

https://www.dxfconverter.org/

I don't know how well it works since I don't have a laser printer to test the SVG on.

 

[martinjaymckee]

So I cut the demo centering rings today ( out of 1/8in lite-ply ). I don't have a 3" tube to check it against, but it slides quite nicely onto the 29mm tube I've got. There's a little slop, but I didn't check the diameters in the file and of the 29mm MMT I've got, nor did I attempt to adjust for the laser kerf. I don't have a picture at the moment, but I'd call this a win. It works quite nicely.

Martin Jay McKee

 

[Winston]

So I cut the demo centering rings today ( out of 1/8in lite-ply ). I don't have a 3" tube to check it against, but it slides quite nicely onto the 29mm tube I've got. There's a little slop, but I didn't check the diameters in the file and of the 29mm MMT I've got, nor did I attempt to adjust for the laser kerf. I don't have a picture at the moment, but I'd call this a win. It works quite nicely.

Martin Jay McKee

Cool. "Laser kerf" - so that's what it's called. I should have known there'd be a specific name for it.