In article ,
Jim Stewart wrote:
Proctologically Violated©® wrote:

Awl--

I acquired this incredible Engleberg 4" pedestal belt sander, but w/ shot
motor, shot driveshaft, on which I've posted elsewhere.

The replacement motor is proving to be a problem. Direct replacment is
possible, but expensive. (Cast iron finned, 1700 rpm, 143 frame).
Rewinding is expensive.

But I've been finding possible motors, but w/ 3450 rpm, 3 ph, 1 hp.

Would this motor on a VFD be a viable solution? As a direct drive unit, I
don't have the luxury of mixing pulley ratios, so would torque be a problem,
at dialed-down speeds--actually, 50% speed?
Would the higher speeds be any advantage for some materials??

Probably not a good idea -- but slower speeds might be an
advantage at times -- for certain plastics to prevent melting.

What are people paying for these sized VFDs?

I have a pair of Hitachi 1hp VFD's on my lathe
and mill. They were NOS and were about $100/ea
They work fine.

That said, a VFD would probably work. I have
no problem with torque at 50% speed.

OTOH, I'd be scared ****less that some sort
of malfunction or missuse would give the motor
100% speeed, or worse - 150% or 200% speed and
detonate the wheel...

But most VFDs have the ability to set a maximum allowed
frequency (you have to spend some time in the manual to find which
parameter to change and how to change it), so there would be no risk of
running at 200% speed.

Enjoy,
DoN.

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