Re: [CAD_CAM_EDM_DRO] Re: Sherline Mill

> I have a Sherline Mill that I am converting to CNC. I have a couple of
> questions I hope somebody can answer for me.
>
> (1) I have 100 oz Steppers for X, Y and a 190 oz Steeper for Z. Will
> these work satisfactory with this size of Mill?

You already have them, so there is no harm in bolting them on to try,
assuming they are NEMA 23 mount which is what any upgrade would likely
be. The machine will run with these, it just won't move as fast
between cuts as it would with bigger motors.

> (2) What about the lead screws that come with the Mill. Are these
> satisfactory for CNC work? Will backlash be a problem with this Factory
> screws?

Yes, ultimately. You can tighten the nuts up but they will eventually
wear loose again. You can also try casting new ones from moglice (I
ordered some today to do my 9" lathe, but should try casting a
sherline nut with some of the leftover).

> (3) I am planing to use a Camtronics 3Axis 2Amp Chopper Driver Board.

Check the current requirements of your motors. Many people use that
board with this size of machine, but by my reading should not
theoretically be able to handle low impedance motors in the 100-150
oz/in range - the motors in this class I've seen all want 3 or even
3.5 amps. Motors which want less current at a higher voltage will not
perform well at high speed.

My sheline has high impedance unipolar motors with a resistive ballast
(aka "LR") drive. It works, it's just very slow...

Chris