Fried Bridgeport motor - repair advice or replacement needed

[TomBoctou]

I volunteer at a Boston-area maker space, Artisan's Asylum. We recently had a nice variable speed head Bridgeport donated. Unfortunately when it had a plug installed one of the hot lines got swapped with neutral or ground, or at least that's what the person who later took the plug off said. The motor ran for a short time, poorly, then the magic smoke came out.

There aren't many motor rewinders around anymore and it looks like replacement windings are $700+, which is a lot to a volunteer-run non-profit organization. Does anyone have any advice for a lower cost fix, or a spare motor they'd sell us?

145TY-4 frame, model F537A, 2 hp 3 phase, needs to be able to work at 208V.

Thanks in advance!

 

[jccaclimber]

Something's up here, was the machine running on 3 phase? If so, the wire order doesn't matter.
If you tried running it on a 240 V single phase connection I can see bad things happening.
At least on my Bridgeport (though an EZ-Trak) there's also a transformer to adjust for incoming voltage. If that as set wrong I could see it letting out the magic smoke.

 

[TomBoctou]

The wire order doesn't matter for the three hot legs, but it appears that running a hot leg into the motor's ground and ground into one of the motor's hot legs is a nono. I'm surprised the whole machine wasn't hot, but nobody got fried.

It doesn't make sense to me, it seems like there was effectively 208 single phase feeding the motor, plus a 110v ground. The person who had run it until the smoke came out said the motor was turning, poorly, and that the plug was wired wrong when they took it apart, but I didn't see how it was actually wired. The mill had been in use before we got it, so an explanation that doesn't really make sense is all I've got.

Regardless, we still need a new motor.

 

[neanderthal mach]

If it were me I think I'd see if H & W has a good used one in stock. https://machinerypartsdepot.com/ For BP parts, there probably the easiest and best way to go, although I have no idea about price. And yeah 2 hp 3 ph motor rewinds are about that in my area as well. At least you can probably get an off the shelf motor. My Taiwan built clone uses the much less available Asian motor standard that don't match up to either of the imperial or metric face mount motor standards.

 

[jccaclimber]

Oddly a rebuilt motor was more than a new one when I looked on the H&W site earlier today.

 

[jackalope]

I have a great 2hp motor available. It’s not cheap at $800 plus shipping but it is a very good quality motor and in great condition. I was going to use it on a rebuild but fixed the 1.5hp that was in it. Lmk. St. Louis, MO area

 

[MwTech Inc]

New on #bay for $1700 so jackalope is looking pretty good............

 

[jackalope]

You may want to disassemble your roasted motor and sell for parts. If the shaft isn’t worn, it could bring a couple hundred. I built an old one up and machined it back to save some money. Point is, you could make some money back on the wasted one instead of just tossing it. Would offset cost of whatever you do buy.

 

[aribert]

I sold a 1.5 hp Bport motor with a fried winding to H&W as a core earlier this year. I was pleased with the monies I got paid for something I had no use for. I'm much closer to H& W so my shipping cost was just under $50.

 

[Rollerman]

Talk to Stearns, Perry, and Smith in Quincy, old line, very old line motor repair shop.
I have used them and recommend them.

 

[stephen thomas]

So no mag starter & heaters; or magnetic contactor/disconnect on the machine?
Are you going to put one on when the motor is replaced?

There's still a couple motor rewinders in this area, but no idea of cost for a BP motor.
I'd definitely explore that option.

 

[RandyHut]

There are several motor manufactures that make motors with end mounting. a flat plate with a couple of properly placed holes and a $300 motor sounds like a better option.

 

[Billtodd]

Shame you're not this side of the pond I have one 240v single phase in my garage

 

[4GSR]

There are several motor manufactures that make motors with end mounting. a flat plate with a couple of properly placed holes and a $300 motor sounds like a better option.

That sounds fine, dandy, and great. The problem is, the OEM motor has a special shaft sticking out that doesn't match up with any standard off the shelf motor. Not too sure if a stub shaft can be added or not. Maybe?

I recall doing this to a old Gorton mill years ago. Took a standard two speed Baldor motor, added a stub shaft to get it long enough to mount the steep sheave on. It worked. This may work on a Bridgeport mill with step sheaves, I doubt it can be done with the VS sheaves.