a quick look at the web site linked didn’t turn up much info on the spindle. That is key to any decent PCB routing as runout must be tightly controlled.

also resolution is just a number, what I would like to see is repeatability! Well that and positioning precision.


in any event I think the professors or students here have misplaced priorities. If one is to build a machine (router or mill) to aid in the invention of electronics you might a well make it robust enough to handle a wide array of electronic production needs. For example have enough rigidity and performance to machine your device chassis / panel. I realize this is likely a project to meet a programs requirements and in that regard it is pretty neat.

Quote Originally Posted by tonyfoale View Post
Interesting post. 10 microns is a good result for such a machine. My son has left me with a 3D printer sans printing head and I have often thought about turning it into a dedicated PCB mill. However, I have a full size mill (Bridgeport) and so as my needs for PCBs are limited there is no motivation to use the 3D printer. It just seems overkill whenever I used the BP for a small circuit board.

I note in the linked description a claim that 2 mm warpage of the base boards is not uncommon as justification for using height compensation. I have never seen anything approaching that except for an overall bow, which is easily fixed with a vacuum chuck or even edge clamping. Here is a post on a small one that I made. More recently I had cause to make a larger one and with only 0.1 mm DOC there has never been uneven depth.
Vacuum chuck for PCB milling and engraving.
I use the G-code straight out of FlatCam without any compensation for warp.

I note also the very slow feed rates used, is that necessary because of the limitations of a machine based on a 3D printer, or is the spindle speed less than optimum? I use feed rates around 10 x those mentioned, with a 24,000 rpm spindle.

Here is a pic of a recent board Click image for larger version. 

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