ger21 --

Upon re-reading my post... yeah; I think it could stand a little clarification. Sorry about that! So...

These days, practically speaking, in this context, 'suitable for Mach 3' translates to 'old', and probably gathering dust in a closet somewhere.

More specifically, for parallel port use, you'd need a machine that passed the Mach 3 timing tests, and, well, had a parallel port. There were a lot of machines from back then that would not pass the timing tests; laptops were the worst in this respect; but a lot of business class desktops with remote management in the BIOS would fail also.

which was originally developed on Windows 2000.
Which is what I was running it on... at the time, I specifically went out on eBay and bought a copy of Windows 2000 just for this purpose. FWIW, I think I still have it around here somewhere....

I do not recommend Mach3 at all, as it's obsolete at this point.
I don't use it anymore; but I still do see it used (various forum posts & YouTube videos lead me to this impression). Perhaps it's just "marketplace inertia" causing this?

There is one use case that I can think of for it today; but otherwise - yes, it's basically an end-of-life product. That one use case I can think of is this:
1) You have a suitable PC gathering dust in a closet somewhere.
2) You are already going to be using stepper drivers that can be directly interfaced with a parallel port using a $3 DB25 breakout board. It helps if the stepper driver has optoisolation built in.
3) You don't have the money for a full Mach 4 (or UCCNC or Masso or... etc) setup yet.
4) Grbl based solutions won't do what you want.

Then you could give it a try, with the demo version first. If it doesn't work out you are only out the $3 for the DB25 breakout board; and some time spent fiddling with it.

I recommend UCCNC,
I haven't used it myself, so I'll have take your word that it's good stuff.

To me, GRBL and all the low cost and open source stuff is more suited to small, very low cost hobby machines.
Well... the X-Carve uses it, and that's available in a size that's slightly larger than what was described here in the original post. I suppose it depends on what you are expecting to get out of the machine as to how suitable it is - it's definitely less feature-packed then the other options mentioned here; but I can say from experience that it does work. It's also available for less than $20 in hardware costs... so I guess you get what you pay for?

Personally, I'm in a bit of an odd position, so what's best for me may well be not best for anybody else... I'm a programmer who dabbles in hardware; and having full access all the way from the G-Code interpreter down to the hardware is tremendously appealing to me. I'm working on the AVR platform right now; but intend to transition to the ARM platform as soon as the official ARM version is out (I've decided not to try to port the existing version of Grbl to an ARM based Arduino; as according to Chamnit, he's completely refactoring Grbl for Arm; and as soon as he does release it, my porting work would be obsolete). One of my motivations in doing the work that I have on Grbl is I wanted to not have a PC hanging off of each CNC machine I have... no PC cost, no PC maintenance, no PC boot time (my version of Grbl is pretty close to "instant on")... more of an "appliance" user experience. Obviously, this won't apply to everyone... or even most people. I'm odd.


Arjay --
I have printed PLA and PETG on my 3D printer (an i3 clone built by WanHao for MonoPrice). My experience is that PLA starts quite rigid at room temperature, and really gets soft quite quickly as temperatures rise; and PETG is slightly softer at room temperature but doesn't soften until much higher temperatures than PLA does. However, the PTEG that I have will soften enough to compromise the rigidity of a motor mount. Perhaps you have better materials than I do (mine is from eSun). I have not tried nylon or CF reinforced filaments; so I can't speak to those.

It's certainly good for prototyping parts that don't have to be rigid or high-strength while being tested; and for some parts I've directly used the 3D prints (they weren't mounts for motors that got hot, though).