Quote Originally Posted by Desertboy View Post
If going the Arduino route you're better off with grbl and a uno/cncshield combo, they're super cheap I paid <£10 for mine on ebay from UK seller.

https://blog.protoneer.co.nz/grbls-p...speed-spindle/

You could also use a variac to control the speed.

Good luck with your build.
I've actually already got one of those for about £4. It seems very... lacking. With the RAMPS1.4 I can add LCD and SD control, better processing and a tonne more peripheral pins if I need them. As Marlin is based on grbl it holds a lot of the functionality and holds a CNC configuration option anyway. So overall it looks like the better option.
Yes, a variac, but see, I'm trying to control the speed automatically. If I wanted to manually control it I'd just move the existing control box to a remote location. I've since solved this issue (run motor as DC via bridge rectifier).
Nevertheless, thanks and thanks again for the good wishes, I'm sure I'll come across a few issues along the way :)