Welding On An Electric Motor

[Bib Overalls]

A weld on my ban saw's motor mounting pad has cracked/failed. It wasn't welded all that good from the factory in China (where else) and the only remedy that I can think of is reinforcing/fixing the existing welds is more weld.

I know that the ground needs to be located where where the current does not flow through he bearings and/or arc inside.

Will this work or is there something else I need to do before welding? I am not particularly adverse to taking the motor apart but I will do it if necessary.

 

[wyliesdiesels]

Post some pics

 

[Bert_]

I would ground to the mounting plate and I don't think you will have an issue. Maybe do a couple short beads allowing it to cool in between.

 

[larry4406]

I’m no welding expert

I was at a power station were welding on a diesel generator frame was needed. Same concern over arcing across bearings causing issues.

The brain trusts at the plant said to connect the ground clamp as close to the weld site as possible. They explained this would prevent the discharge path going thru the bearings. I do know machine ran ok afterwords but no clue if any long term impact. YMMV.

 

[Milton Shaw]

I welded a bracket on a motor several years ago, short welds and let cool.. No problems have used it nearly twenty years now. So give it a try if its out of warranty. Ground to the bracket and you should be OK.

 

[sberry]

Only concern is melting something on the back side.

 

[nadogail]

As the others have said, avoid having the welding current pass through bearings, bushings or brushes. The shortest path to ground and short beads with lots of cooling are also important.

 

[dogdog]

I would worry about melting those winding (wire insulation) than worry about ground... as long as you disconnect the power and the caps... Not sure if welding current would pass through the bearing unless you clamp on it...

have a 2HP where the UPS monkey throws around like a step child and broke the casted legs that way.

 

[Bib Overalls]

Thanks guys. I am going to do the welding later this week and I will post a report when I am finished.

 

[alfredeneuman]

If your going to weld the base some wet rags wrapped around the motor itself will help to see that you don't damage it.

 

[Jim greengo]

Make sure you have a really good ground to the plate when you do it.

 

[nsula_country]

Done it several times on 180VDC motors.

Ground it close.

CT