Building up shafts

I want to build up shafts from a tractor where seals have worn a groove. Would spray welding and grinding down on a lathe with a tool post grinder work?? Tell me something about spray welding I have only heard about it.

I've heard of spray welding but never have seen it done. I have built shaft up by welding then turned down to nominal diameter. I've also cleaned shafts with emery cloth and used jb weld with good results. May look into a speedy sleave. Autoparts store have these or can get any size you may need.

I use to do a lot of it in special situations. prep work is key to success. I would turn shaft to clean it up. then cut some rough shallow treads for a mechanical lock of sorts. it also provided slightly more surface area for spray to bond to shaft. you'll need a few temp sticks for correct temperature of shaft. most important don't touch the shaft after you have it prepped. the oil on your fingers will not let spray bond. I would think any well equipped machine shop can do this for you. the special torch and powders are very expensive to purchase, but if done right it works. it was easier and cheaper to sleeve most parts however. good luck

agree with others - speedi sleeve is the way to go.

Would it be possible to reposition the seal... I have cut washers out of a 5 gal. bucket and installed it behind the seal to space it out... Theirs also the option of machining the hub are seal so it will set deeper in its retainer... If you have that option you can also double seal it...

What size shaft? On a Ford PS pump, a shop didn't want to spray-weld because on a shaft that small, they'd seen them hot-dog warp end-to-end. For our shaft, they cut a strip much longer than the seal area, then sprayed a ceramic coating into that, then ground and polished. It had to be carefully done because of the pump pressures the seal has to hold. They said it would utlast me. Cost was a bit pricey - $150 - but another pump was several times that.

Ted,

Spray it , spray works well for that use.

If you have a lathe, I have a couple of extra

eutectic rototech spray torches. Bought them in

package deals.

george

I had a spray torch when I was teaching welding back in the 80's. Thought I would be smart and coat my bush hog blades. Rockwell 95 I think. I fixed them where they were so hard I couldn't sharpen them. Ellis

(quoted from post at 17:30:34 11/18/13) I had a spray torch when I was teaching welding back in the 80's. Thought I would be smart and coat my bush hog blades. Rockwell 95 I think. I fixed them where they were so hard I couldn't sharpen them. Ellis

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That's not possible.

I have been in the business of marketing, training and consulting in regard to repair welding and thermal spray metallizing for over 35 years. When I hear spray welding I'm never quite sure which process is being referred to.

The Rototec one gentleman has mentioned is an antiquated system once marketed by Eutectic in their heyday.

That system or any of its modern derivatives is IMHO the very best way to repair most worn or damaged bearing fits or seal areas. (The Rototec would be my last choice)You might be very surprised to find out where thermal spray coatings are being utilized in every day modern life.

The combustion torch process, which is essentially what the old Rototec torch developed into, if used correctly, imparts less than 450°F into the part. Selecting the proper powder alloy for use is key to maximum life expectancy of the coated part.

Not enough space here to go into much detail, but, a coating that can be machined with carbide tooling is a very practical choice for your seal area.

PS. A spray and fuse coating was mentioned here for use on mower blades. That is a phenomenal process for use in that regard. The reason it was difficult to sharpen the blade afterwards was due to the fact that it was improperly applied. You don't spray the actual cutting edge. If I had more space I would explain the way that's done.

Cordially,

Steve