Does anyone know an easy way to convert a CAD file from Calum Audio into a cutlist for CNC. I haven't had an experience with CAD software since I was in school.
Planning on building a couple hog scoops using the plans from Calum, my mates work has a CNC router I can use but I am having trouble converting the CAD file into something 2D for the CNC router. I'm using FreeCAD which probably isn't the best. Thanks in advance.
Hey Dan,
Great question, I get asked this quite a lot so I guess it’s worth taking the time to write out something proper.
I decided a while ago that all the CAD file’s I’d offer would be in the STEP format, this is a pretty widely accepted and fairly standard 3D CAD format. When I first looked at going open source some years ago I quickly realised that I’d potentially end up in a situation where I’d have a vast number of files / folders / changelogs to keep track of if I wasn’t careful. This led me to take the decision to offer ‘assembly’ models of cabinets containing multiple bodies, rather than directories of individual bodies. This reduced the number of files I had to keep track of from several hundred to just a few dozen. I felt like while it added in some extra steps for all of you later down the line, I could do a better job of putting out the files and keeping track of where everything was, and especially what revision everything was.
For some clarity, the ‘assembly’ models I have put out are one individual STEP file that’s a full 3D assembly of all of the panels within a cabinet (sometimes it includes hardware too) – but within the file all of the different parts or panels are ‘individual’ and you should be able to open, view and access them one at a time.
What this means is that the first step for everyone when using the STEP files I’ve put out, is to isolate and pull out the individual bodies contained within the assembly file. Any half decent CAD package will have a dedicated tool or function to achieve this, with a bit of googling I’m sure you can find how your package does this. Look for something like ‘isolate bodies’ or ‘keep bodies’ or 'split bodies’. Some CAD packages even have the option to automatically break down a STEP file into all the individual bodies upon exporting it from the package (often found under something like ‘step export settings’) – you could just re-export the assembly file as a new STEP file with this feature enabled and you’d automatically get a directory of the individual bodies. *note, this is the feature that I decided not to use when I did all my initial exports to avoid having hundreds of files to keep track of.
With a little time you should easily be able to create a folder of all the individual files you need to build a full cabinet.
Depending on the CAM software that you use, it’s often possible to drop the full 3D panels into the software. This saves a huge amount of time going back and forth to define Z heights later on. If you can’t do this and require 2D files, you need to take the individual panel or part files that you need to cut, open the 3D step files in your CAD software and (after choosing a suitable plane to work from) export the view of one plane as a DXF. Again, almost all half decent CAD packages will have this feature. Just be wary that you have now lost all the depth information that was in the STEP and you need to know this later on when you program the cutting.
Based on the above you should now have a folder with all of the relevant 2D or 3D files that you need to import into your CAM software.
For those of you without a CNC router, it’s pretty simple to take either the 2D or 3D files (whichever you prefer to work with) and find out the external dimensions of all the panels, create a ‘manual’ cut list of parts and feed it into a website like cutlistoptimizer to generate a cut sheet.
I hope this helps!
Calum
