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well i got the motor back from the rebuild shop, purrs like a kitten , only, it is running backwards! is it tough to reverse the spin on one of these motors? I have the old delta with four graduated pullies on the motor shaft and four on the driling shaft, does anyone have an idea how to (roughly) compute RPM's? or is it just slow , not as slow , faster, fastest ? LOL thanks jody

Jody, if the people who rebuilt the motor made it run in reverse, take it back to them and have them switch it. There may be an easy way to switch it, but I'll not comment on that as I'm not sure.

As far as calculating the speeds...it is just a ratio of the sizes of the pulleys involved. Therefore, if the motor is running at 1725 rpm and the pulley on the motor shaft is 2 inches in diam, and the one of the other end is 4 inches...your speed is cut in half. If it's 1.5 inches and 2.5 inches then it's 1035 rpm.

Darrin

Jody, when you wired the motor back in you may have got the wires on the wrong pole. Try switching them.

And what Darrin said about the speed. Measure your pullies diameter and make a little chart to tape on the wall by your drill press.

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I have an old Delta Milwaukee, and I know the old motor could be wired to run in either direction. My father actually put a switch on it so he could reverse it. Sadly, that motor burned up, and I had to replace it with a newer motor, which does not have the same feature. There is a plate on the top or bottom of the motor where the wiring can be changed to correct the rotation. You might want to get them to do it for you, if you aren't comfortable with changing it yourself.

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Thanks guys! I think I will talk to them about the motor as I am not sure.. maybe they can explain it so I don't need to remove it . thanks ! jody

Unplug the machine. Pull the cover plate.

Look for a little picture which shows all numbered terminals

and maybe color coded.

It shows how to wire 110 and 220 Volts and how to place the wires.

If reversible, it will show that. It's usually just a few wire change.

Wires which appear simply to hook to each other in a junction do.

The ones that go to terminals, screw or spade connector, are easy to determine.

Might save you a trip to the shop and get you going.

Post a pic and we'll coach you.

Or, you can take it back as suggested, it's not a biggie.

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Thanks Bruce, I took it back this afternoon , spoke with the fellow, he was saying he might need to take it apart because the guts are way up front where the shaft comes out of the housing.the only thing I know is its a very old motor. Jody

Failing a fix, you'll have to get drill bits that cut in the opposite direction.

I just picked up an old table saw from my father-in-law, an it has a switch wired in that allows the user to reverse direction of the motor. I have no idea why he wired it that way, or how it works, I just mention it to say that there is a simple fix.

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If it's a normal AC single phase induction motor then they reversed the start windings from the running windings from the way it was before. So the leads might not be at the pecker head . Seems like they would have checked the rotation before it left the shop. Normal rotation of a motor is clockwise when viewed from the back of the motor for anyone who doesn't know which is nice to know for a new comer when using a router.