Re: [CAD_CAM_EDM_DRO] Re: ball screw conversion

Hi Will,

I have multiple electronic handwheels (high resolution MPGs), one per
axis and I find I use them an awful lot. I never jog using the keyboard.
With electronic handwheels you don't have any 'feel' for the cut but
you can compensate by listening to the cut instead. Using MPGs in this
way gives you the best of both worlds. The control software always knows
exactly where the machine is so you can mix MPG moves and MDI moves and
you have conveniend DROs showing your position. I do this on my
Colchester lathe running EMC and my mill running Mach. On the lathe I
also have a switch that sets the scaling of the wheels so you can
rapidly move the saddle from one end of the bed to the other or easily
take tiny precision cuts at the flick of a switch.

The handwheels are ordinary machine handwheels mounted on a shaft that
is supported by a couple of skate bearings. The shaft has a friction
brake to give it a bit of resistance. On the back of the assembly I have
a cheap 500 line encoder.

Les

Will Holding wrote:

> I think he meant homeshopcnc.com
>
> You can also mount the handwheels to your pulleys. Unless you provide a way to remove the belts or make one of the pulleys freewheel, you will get cogging from the steppers when using your handwheel, go fast enough and the stepper will suddenly try to brake your handwheel motion. Rather annoying IMO.
>
> You will find you don't need the handwheels at all. People told me this and I didn't listen.Using a pendant jog stick or even the keyboard is much better than hand turning the wheels, it's like having a perfect power feed in all directions.
>
> You really will never use the handwheels- even for picking up a center.
>
> My .02
> -Will
>
>