View Full Version : Looking for tips on a new machine build...

02-07-2016, 05:20 AM
Been pondering over one of the cheap CNC engraver/mills on eBay known as 3040, 6040 etc to mess around with furthering my learning of CNC (CNC plasma is a bit limiting) and having some fun with Aluminium, engraving, signs etc all small stuff and I don't want to be hogging off 4lb of metal per pass:D Probably looking at a cut area of 300x500mm??

Feedback from other places seems to indicate these machines are junk mostly unless heavily modded so a DIY build seems a better option having learnt a lot during designing and building my plasma table.

So, searching for design tips here, getting my notepad out...

1605 ballscrews ok or overkill? Gives a step resolution of 0.025mm at 5mm/200steps and theoretical speed of 3000mm/min at 5mm/600rpm

Never having used ballscrews though, how do I arrive at a motor size easily? No point in throwing massive stepper motors at it if not needed - just increases PSU, weight, cost etc. 2, 3, 4Nm??? Bear in mind I want slaved drives on the long axis. Or do i want a single drive with a fixed gantry & moving bed but that makes the footprint much larger.

HiWin rails I think are good, based on my Plasma build, these would give a very rigid motion system I think, even the small ones are good.

Frame built from Alu or steel? Alu would be a milled, bolt together design much like the 6040's, whereas steel could be plasma cut and welded.

Any ideas for a bed/cutting surface?

Feel free to chime in with any tips.

This may never come to a project as funds are not endless, but who knows ;)