I’ve been watching a fair number of nomad videos here and there, while I wait for my machine/licenses to come. Something that I noticed is that there are a lot of cases where the paths seems to be suboptimal - in particular for PCB milling where a part of the board gets done, then there is a rapid to the other end of the board, and a little more gets done, then back to something close to (but not the same as) the first area… Lots of rapids, when it seems that there could have been an optimization there. Is there a step that would normally be done to optimize there paths that I’m not seeing (can’t play with meshcam…my trial ran out…machine not here yet)?
There are G-code utilities which may address this http://www.shapeoko.com/wiki/index.php/G-Code_Utilities
Some previewers allow one to address this as well: http://www.shapeoko.com/wiki/index.php/Previewing_G-Code
MeshCAM is pretty good about path optimization but it’s not perfectly ideal. No CAM package is… the eternal quest. My high end CAM package - big $$$ - does an amazing job of never wasting a move or cut… and it still sometimes will do something that I can see was a waste.
There are settings that one can use in MeshCAM that improve things. They aren’t always used so watching videos isn’t always the best way to appreciate what MeshCAM can do.
I can’t speak to the PCB software. The ones I’ve seen pursue correctness over minimal time so I’m not surprised by what you report.
To answer your direct question, @mikep, no, there are no optimization settings in MeshCAM. For 3D objects (the type of work MeshCAM was designed for) you can generally maximize cutting efficiency by balancing parameters (waterline vs. parallel finishing, limiting surface angles, etc.) but a PCB is far from that kind of work.
I’ll have to run some jobs though some of these optimization tools and see what they do. I can compare the result to MeshCAM with good settings and my (high end) CAM program. Should be interesting.
I wouldn’t trust aftermarket optimizers without a serious study of the results with a simulator. I don’t doubt that some simply optimizations can make a more than fair improvement.
I can say that I’ve seen my CAM program handle some jobs 2X faster than MeshCAM. These were largely 2D jobs where MeshCAM isn’t primarily aimed. For 3D jobs, the difference isn’t anywhere near that much… often less than10-20% slower than my (high end) CAM program… but quite a bit easier to use!
The key, as I hinted at and @Randy stated, is to learn how to set MeshCAM up with effective settings. Once learned, it competes well with programs costing many times its cost (where the jobs are similar).
I found a fork of the “Gcode Optimizer” (last one in the list at G-Code_Utilities) that was set up to build somewhere other than windows (cmake), and did a tweak to get it to build properly with clang on osx. Anyone that is interested is welcome to it here:
I know it builds properly on OSX, can’t confirm it still does anywhere else, but it should.
Just to be clear, not saying it does anything good, just that it builds.
If you have the cash then I heartily recommend Solidworks with the HSM plug in,it doesnt do the traversing,it can order in islands,operator order,by depth…it can even do thin walled parts by doing both sides together so thin walls are not deformed by the cutter. And,yes,It exports in GRBL with no (so far,22 jobs in) errors.
Free is good,paid for has advantages…
Solidworks isnt free but the plug-in is,if you dont need the support then there are methods of gaining a working SW…
$4K is a little steep for me. Fusion 360 is pretty good though, and free is a pretty good deal. Have considered Rhino a few times.
The gcode-optimizer mutilates a 3D program. It seems to do OK with a 2d job, but it gets the passes out of order for a 3D job.
Fusion 360 is definitely the one to consider - basic and pro level (which costs not too much per year).
There are other choices, many much less than $2K. If you’re willing to move to high end CAD/CAM, it can be discussed. There are packages that do significant path optimization, HSM, and other wonders. Besides the initial cost, there is the time commitment to learn.
It all depends on how much you care about optimization and how much you want the package to do for you.
Kind of comes down to satisfying my own curiosity at this point. How well this is done is actually pretty irrelevant for anything I do, but it was an interesting problem in my head, so thought I would poke at it a little. I use Fusion 360…poorly…but getting better.