sjmartin7441

I recently purchased a older Unisaw (SN55-9037) the delta vintage project shows this saw being produced in 1947. The motor is a PH3 3hp 1725rpm. My research so far makes me think I would be better off purchasing a used 3hp ph1 3450rpm unisaw motor rather than purchasing a phase converter.

Any comments on the benefts/problems with a phase converter. Does any one know what the frame # should be on a 3hp ph1 3450rpm motor. I've seen reference to more than a couple. The current 3hp 3ph motor has a frame # of 184Z. Will all motors than fit this saw require the same frame number.

If I decide to purchase a used 3hp Ph1 3450rpm motor I'll have to replace the pulleys does this effect the frame #?

Any help will be greatly appreciated, I'm somewhat confused at this point

user4178

There is a older Delta / Rockwell Unisaw in a cabinet shop that is up for sale in my area for $400 with a 50" biesemeyer fence, It is a 3 hp, three phase also. I did some reading on phase converters and someone mentioned that you lose about 1/3 of the hp when you use one. Then I looked up the price of a new 3 hp, single phase motor for a Unisaw, they are about $450. Since it's been used in a cabinet shop, I wonder what kind of shape the arbor bearings, the arbor and the gears are in. I could see it possibly being a big money pit. Why would you need to replace the pulleys ?

sjmartin7441

From what I have read the ph3 3hp motor runs at 1725rpm and the different size( from current model pulleys) pulleys upgrades the lower rpm to somewhere in the area of 3000 rpms. Therefore, since the current 3hp ph1 motors already run at 3450rpm the pulleys must be replaced.

user4178

Wouldn't you only have to change the motor pulley ? Or if you look around maybe you could find a single phase 1725 rpm Unisaw motor.