Help and advice

[Simon M]

Good morning,

This is my first post so please forgive me if this is in the wrong sub-forum and has been covered in previous posts. I have searched but not really found what I have been looking for.

I am currently working on a very modest fixed gantry style machine with a work area of around 450*450*200. I have almost completed (if such a thing is possible) the X & Y axes and I am now turning my attention to the Z. I have an overall design in mind for this but to move forward I need to select a spindle. It is at this point I have no experience of what would be a good choice? I am trying to avoid the scenario of buying the wrong spindle and replacing it a year later.

My machining background is from manual hobby machines -Warco 290V lathe and WM18B Mill and before that the ubiquitous Myford ML7 and Clarke metalworker. The plans for the machine is to primarily cut Aluminium, plastics and maybe the odd bit of dead tree carcass but I am also hoping by keeping the DOC small I will be able to cut steel components for the restoration projects I am planning (Westfield 7 and T140V Bonny).

I am thinking of running Mach4 although I have yet to find a motion controller I am happy with so any advice here would also be welcome?

Thanks in advance for any input from you more experienced guys out there.

Regards
Simon

[Neale]

This is not a recommendation, just one data point from one user to get the ball rolling...

My gantry router uses the ubiquitous 3HP 24K RPM Huang Yuan (or is that Huan Yuang?) water-cooled spindle. Fine for cutting wood and plastic, and also done some fine engraving in brass without problems. I have also cut steel, generally profiling cuts in up to 3mm steel sheet, but the problem is minimum spindle speed. I seem to remember that this spindle is notionally rated down to 6K RPM but I found that I could stall the spindle at that speed if not very careful. I ended up running at about 7K minimum with 3mm carbide cutters and DOC set to not stall the thing. Mine is a fairly stiff steel-framed machine. My feeling is that you could do a fair bit of steel cutting but slowly! I later bought a CNC mill running the same cutters at about 4K and that works much better. In general, there is a limit to "one machine for everything". Probably why there are examples of people adding a high-speed spindle to a conventional mill for when those high speeds are needed.

I'm sure that others will have different views!

[JohnHaine]

Which motion controllers have you tested and what problems have you found? FWIW I use uc100s on my mill and lathe and they have been trouble free.