Motor shaft repair

Pcmaker

Pcmaker

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I have a small 1HP pool motor that has a shaft that's damaged. It's about .600 in diameter and about 16" in length

I plan on TIG welding the gouges on the shaft, then turning on my lathe down to its proper diameter. The main part I need repaired is where the bearing is pressed into. I guess the other areas don't matter too much.

Do you think it's safe to do so? I'm worried about warping the shaft with the heat due to it being on the thinner side.
 
There are several critical areas on an integral pump motor shaft. The two bearing journals, the pump packing journal, and the impeller mounting journal. All must be in line and concentric.

Is the new bearing loose on the shaft? If not, set it up in the motor housing and see if the shaft is still straight when rotated using the new bearings. If it has little or no runout, install the bearing with one of the grades of Loctite used for this type of repair. If the new bearing is loose, consider using a less dramatic way of building up the journal. A steel-infused epoxy is one method. Build up with the epoxy and use the lathe to turn the diameter to fit the bore of the bearing. Loctite can compensate for a little loose fit and/or poor surface finish if you use the correct grade.
 
Building up a shaft with weld is an art, one I never learned. You have to balance the stresses or the shaft will warp. It is best done using something to rotate the shaft as you weld. I have always found a way to sleeve the shaft in order to avoid the unpleasant surprises that frequently come with welding. A shaft that small is going to warp easily. First choice would be a Speedi-Sleeve if available in the proper size. Next choice is make a sleeve. Sometimes you have to make a two piece sleeve and TIG the two halves together around the shaft, with just a little dab of weld at each end to secure it to the shaft.
 
Welded many a motor shafts, big and not so big. There is no doubt in my mind that you will cause a bend. You can straighten with heat ( oxy/acet torch) but it's an art. Straightening with a press will work also. Probably will need to do it again after removing some of the weld.
 
Maybe give some consideration to replacing the shaft. It's not that hard to do and you sidestep all the warp issues.:encourage:
 
Warp, schwarp. Of course it's going to warp. And the fix for that is two V blocks and a dial indicator. It's not hard to fix a warped shaft, the steel will comply with nudges and pressure. Before we started throwing everything that breaks away, every old codger could handle straightening a shaft. Try it!
 
This sounds like something I would do.

There is an art to straightening shafts, another to straighten bar and another altogether to straighten plate.

Each behaves slightly different with plate being the worst, but their all doable.
 
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