Thread: Electric motor choice

Dear Quasi,

I seem to recall reading somewhere that the 4-polers do indeed have more torque than the 2-polers, but the thing is, with the 4-pole motor you will have to run a pulley set that will be twice as "tall" as you would with the 2-pole, and this will simply "present" a load that inflicts twice as much torque resistance on the motor...

That being the case, I would therefore opt for the 2-pole unit, because it's directly-driven fan will be spinning at twice as many RPM as the 4-poler, and will therefore provide better cooling.

Best Wishes,
Batpig.

Thanks Batpig.

I see there's a 3/4 hp motor in the Weekend Shopper that may suit.

Hi Quasi,
AC Hargreaves at 17 mile Rocks are experts. Call them. (achargreaves.com.au)

Cheers,
conwood

FWIW I'd see about a bigger motor than that. I have a 12" p/t powered by a 4 hp three phase and is too small*. I'd like a 7.5 hp for the 12" machine, so you might be better served by a three h.p if you can get a single phase motor cheaply in that size. No insights into pole count.

*fine on the planer, but bogs down thicknessing greater than (say) 3mm in boards wider than about 150mm. Taking big bites out of planks might not be an issue for you, but I find I'm often up against the h.p. limit when doing a lot of milling.

Good luck

Greg

Thanks for your suggestions - now all I need is some time to strip it down and repaint, make a stand etc etc.

I will try to take some photographs of the rebuild and post them for your opinions in due course.

I bought a secondhand 6" Durden jointer about 6 years ago. It had a 1hp 3phase motor, I repowered it with a 1.5hp CMG 2pole single phase motor.
It has more than enough power now, doesnt bog down, even with heavy cuts.
1 1/2 hp may be overkill, but I am not going to downsize to find out.

The new motor cost me more than the rest of the machine

Thanks Ironwood - as they say, it's better to have it (in this case - sufficient power) and not need it, than need it and not have it.