Open source 2.5 CAM software?

Hey fellow makers, I’m hoping to get my OpenBuilds Ox CNC router back up and running after a long kitchen remodel put my garage toys out of commission. Part of that is I have switched my host PC from old Windows 7 to Linux Mint Cinnamon. I have CNC.js installed, which is what I used before. But I have also installed bCNC. Looking at its UI, I see it does CAM (but heck if I can figure out its confusing UI). Before I spend too much time trying to figure out it’s CAM UI, I’m wondering if it does 2.5d? Does anyone here know? Documentation seems sparse and outdated.

Barring that, does anyone know of a decent OSS CAM that will do double-sided 2.5d? (as in, flip it over for full 3D) I think Kiri:Moto does, but it doesn’t look like does. uses flash, so that is a non-starter for me. If I can’t find a good OSS CAM, I may just use ESTLCAM (not OSS, but cheap and does 2-sided jobs). Although, come to think of it, I’m not sure it does Linux.

Also, Merry Christmas :christmas_tree::gift: everyone! :nerd_face::+1:


In theory, you should be able to do double sided jobs with FreeCAD. You’ll need to figure out the positioning and stuff manually though. :slight_smile:


Did you mean FreeCAD? “FreeCAM” appears to be screen recording software.

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Ah FreeCAD. I wish the CAM defaults weren’t so crazy. Defaulting the step down to the end mill diameter seems like a great way to break a bit (e.g. 1/8” end mill is 3.175mm diameter. 3.175mm step down is the default for a pocket operation. My spindle only runs 10k rpm or less, so I run it at 10k rpm. I don’t know, maybe I should just slow down my feed rate to match these defaults? But, what if I was cutting aluminum instead of wood? This stuff is buried pretty deep in the UI. Don’t get me wrong—I love FreeCAD. But the CAM UI…not so much.

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Oops, yes FreeCAD. Fixed the typo. :slight_smile:

And yeah, like any CAM package it has a lot of warts.

That being said, it wasn’t super hard to compile when I was last using it. So, depending on how much those defaults piss you off… you could change them. :slight_smile:

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I thought the defaults were 1/2 tool diameter, and am not sure whether my memory is foggy from months of not toolpathing while my router was in the shambles of a rebuild, or (perhaps) I found a way to set the defaults across jobs? It wasn’t a strong memory because step down is one of the things I change a lot anyway, for better or worse. [Edit: it does seem to default to OpToolDiameter which is a little enthusiastic to my hobbyist eye…]

Note that the Path workbench is one of the things that has had a lot of work in the 0.19 cycle. One of the things that drives me up the wall about FreeCAD is that they put downloading 0.18 front and center on their web site, but then when people report bugs they say they don’t accept bug reports there any more please use the beta, it’s more stable than the previous stable release, but they still won’t move the 0.19 beta above the fold on their web site. Very mixed signals there.

In particular, the grbl post in 0.19 can finally actually work with grbl, without requiring that the sender process macros (such as drill cycles). I just recently toolpathed using 0.19 (probably realthunder’s linkstage3 branch) and I’m pretty confident that I set a custom step-down without even looking at what the default was.


Relevant to that…


Cool! I’ll check this out later. Thanks!

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Wow–they’ve really updated the UI/features since the last time I looked at it!

This video is NEW! (1/1/2021) Here is a direct link to jump to the an explanation of the CAM features:


See also the new registration option that doesn’t need pins…