Re: metric to imperial shaft adapters for stepper motor??

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Mike Mueller"
<mueller914@y...> wrote:

>
> I'm replacing a sigma stepper on my bridgeport with a sanyo denki
> stepper motor. I made the error of assuming that it would be a bolt-
> on due to it being the same NEMA 42 frame size..guess not :)
>
> shaft is a tad too large in diameter (metric I'm guessing right now)
> and it's too short, about a good inch.

I did consider replacing the steppers on my bridgeport with modern
ones ... but like you have found, it would need to extend the shafts a
fair way. I thought about it and in the end, decided the side loading
of a large pulley and belt drive that distance from the bearing, on an
adaptor, was a Bad Plan (tm) so we stuck with the original ones. Those
old bridgeport steppers are mechanically massive, Im not sure the
shaft on a NEMA42 is quite as robust .. IF I was to do this, I think
I'd go for some nicely turned up adaptor and lock it on with a
"Trantorque" bush or another similar type of "allround" grippign bush,
plus make sure I ream the sahft hole to a tight fit. theres a lot of
potential for extension piece to wobble, I dont think you'll get away
with a couple of grub-screws on this one.