David Billington prodded the keyboard

On 29/01/15 14:46, Baron wrote:
Terry Coombs prodded the keyboard

Got any stepper motors for cheep? I think nema 34's will work
, I want to
power the X axis and maybe the Y on my benchtop mill . I have (or
have components to build) controllers and power supplies , can
fabricate mounts
and the rest in house . I actually had an 18v HF drill motor all
but mounted , using a PWM controller and a 13.5 volt supply . At
the speeds I need it didn't have enough torque - though I may
revisit that setup now that I can cut gears .
And speaking of cutting gears , how about cutting pulleys for
cogged belts
, anybody got experience doing that that they'd like to share ?
--
Snag
As if I didn't have enough in the works ... but a powered X
on the mill will make some of that a LOT easier!
Have you considered car wiper motors ?

See my build log :-
http://www.homemodelenginemachinist.com/showthread.php?t=23130
You will need to register to see the pictures.

One issue with typical wiper motors is they're only intended to
rotate in one direction and in my experience don't run as well in
the reverse direction. The few I have taken apart only have thrust
provision for the intended direction. I have used them to run in
both direction and it worked OK. Window winder motors are
bidirectional and have thrust pads at both end of the shaft on the
ones I've dismantled.

Yes that's true ! Which is one reason that I used a tumbler gear
mechanism to reverse the table direction. Limit switches take care
of running into the ends of the table.

As far as servoing is concerned, isn't that what the DRO is for. Set
zero and run to value "X" then stop.


--
Best Regards:
Baron.