Tigging vs stick welding a shaft

No matter which process you choose, the bearing race will be the hardest thing in the equation. That said, porosity, slag inclusions, etc.. will not be a major issue beneath the bearing race.

I would stick weld it (really I would MIG it but that does not seem to be an option for you). Weld it like you were tightening a bolt circle (12 o'clock, then 6 o'clock, then 3 o'clock etc...). When it is all welded up, allow it to cool standing on end. Machine it down and you should have a relatively true shaft.

This is assuming that the shaft is for something like a manure spreader or chuck wagon, not a shaft where personnel safety is an issue.

Shawn

I helped a machinist / welder weld some kind of shaft one time and thought the tig worked out very well because of not having to start and stop. I'd twist my arms all the way around it so I could make a complete revolution without stopping and he'd tig it. I tried to keep a steady pace but occasionally he's say, "speed up a little" or "slow down". I'm not sure what it was going on - or if he had to turn it afterward. I know we made several passes all the way around.

Seems to me, from the inexperienced perspective, that if you kept the shaft cool by wrapping it in a sopping wet (ice cold water, even) towel, that you could hit it with the stick for a short very bead, let it cool quickly, repeat on opposite sides as you go around. Current up as high as you can get away with to get metal down as fast as you can so nothing else heats up.

TIG.

If you have a lathe, mount the shaft and rotate slowly. Work clamp directly to the shaft. DO NOT ground through the lathe.one pass all the way around, let cool. Again. Again. Put on a LITTLE extra and machine it off, to anneal the deposit and leave clean surface. Expect to need to straighten a shaft this small.

If I were doing it, I would use a couple of vee blocks to hold the shaft while welding it. Vee blocks with clamps so the shaft is held straight while welding. After welding check the shaft for straightness. If not straight, I would heat it and apply pressure to straighten it.

Dan

One addition to this. If you plan to machine this you may want to cut some extra off BEFORE welding so you don't wind up trying to mill the original material and the new material at the same time. Different hardnesses can create a problem. I know a machinist who ALWAYS cuts plenty of metal away initially so he is only milling his new material to a finished product.

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enl snipped-for-privacy@yahoo.com wrote:

I have TIG welded up shafts before, and my problem was the weld deposit got too hard to machine. Build it up with Stainless and you wouldn't have that problem. It's worse on large shafts because they suck up the heat and cool the weld fast. A good preheat might overcome this problem.

I now have a flame spray outfit to do shafts, works real nice.

remove 333 to email reply. Thanks, Randy