To answer a couple of questions:

Well of course you will not be able to mill steel or probably not even any kind of metal. But all the DIY CNC machines rely on pretty stock NEMA17 motors, which are the same as Solidoodle uses. And while I guess leadscrews would be better, quite a few use transmission belts anyway. So in principle the motors should provide enough force for some milling. Maybe you have some low voltage on the trimpots, or the belts are too loose?

The cutter head is at the moment not stiff enough, but I will try to address this problem. The real big problem from a mechanical point of view is the bed, which is not very stiff or robust (and I even have the plywood version!) and it has to raise actively against the bit... It would have been better to have a head that pushes down instead. But we will see.

As mentioned above, grbl seems to be the "gold standard" but I want to be able to use Marlin, since I don't want to change the firmware every time. Anyway, I basically only use the movement commands (the bit rotation is controlled by hand). I found this nice script https://bitbucket.org/raw/cnc_mendel/src that converts pycam code into marlin GCode. You will still need to edit it a bit by hand, but it works in principle.

What I tried was to move the bit to the bottom-left of the area where I wanted to engrave, lowered it until it touched the wood and then I run a G92 X0 Y0 Z0 to redefine the "home" there. And then I could let the script run. The engraving failed because of mechanical reason, this will be fixed in the next release cycle

Ah, nice ! I just ordered myself a cnc 6040 mil from a Chinese company to have something new to tinker with. Starting to realize it will be hard to run it in my apartment

These are kinda loud, but nothing you cannot tone down by making an enclosure out of acrylic (thin stuff bent with a heat gun) and lined with acoustic foam, make sure you leave a large clear window in the foam in each side & top so you can monitor the work. It will keep the chips under control & the noise will be nicely muffled.

I have the 3020 & they use the same NEMA motors & it isn't terribly loud during rapids. The only concern I think would be the shaping, as vibration screams in small rooms.

You can also set a sturdy layer of firm foam under the unit to isolate noise from below.

https://www.facebook.com/photo.php?v=60 … mp;theater

Ah, nice ! I just ordered myself a cnc 6040 mil from a Chinese company to have something new to tinker with. Starting to realize it will be hard to run it in my apartment

maybe you should troubleshoot that, because my axes have only skipped when I crashed the print head.  I'm quite thankful for that too!  Perhaps your tension is too low?

OP:  what do you plan to do with sawdust?

Nice work!
...
But once again, nice work! Have you found any good software to run the arduino based controller as a cnc?

Perhaps the most common would be grbl.

But once again, nice work! Have you found any good software to run the arduino based controller as a cnc?

Does any know if any of the M, G, etc. commands currently in the firmware stomp on CNC codes?  Could the two "modes" coexist in both firmware and interface software?

Matt

I thought that the Solidoodle carriage wouldn't hold a dremel or something similar, but it could work with a flex shaft. So I did:

Here's a video of it drilling into some wood:

And here with a mill head drawing some straight lines:

In these videos I was moving the head manually with a feedrate of 40.

This setup is still far from usable, including the fact that I will need to change the flex shaft with a better one (the one I have now is too flexible), but I think it has potential. Maybe not for milling steel, but wood and PCB (my ultimate goal) should be feasible.