repairing a bent shaft with lathe with jack

[Smithdoor]

How many have repairing a bent shaft with lathe with jack and chisel

I have done this with shaft up to 8" and 1 1/2 ton jack

Dave

 

[Terrywerm]

I have used a lathe to see if a shaft is straight, but have never used a jack in the lathe to straighten the bent shaft. How does the chisel come into play?

 

[zimma]

I would tend to use the lathe to spin the part, and use an indicator to locate and mark the point of maximum runout. Then transfer the part sitting on two Vee blocks/supports and put into the hydraulic press. Return to lathe after pressing, and repeat process until done.

I'm no expert on the rigidity of larger machines (bending an 8" bar in a lathe must require quite a force), but I really don't think that would do either your chuck, or your headstock bearings any good at all.

 

[Bill Gruby]

I'll bet your spindle bearings are taking a beating. They weren't meant to take that kind of stress. They are axial bearings or tapered roller bearings. Not a good thing to do to them in IMHO.

"Billy G"

 

[Smithdoor]

I found this when I was work some else shop
Just put a small jack at the bend with little presser. Take the a dill chisel on the other side and hit the shaft
I have straighten shaft with of 0.050 bend to tir of 0.0005"

FYI the first I saw this I did think it would work and it was a big joke
But it work great

Dave

I have used a lathe to see if a shaft is straight, but have never used a jack in the lathe to straighten the bent shaft. How does the chisel come into play?

 

[chips&more]

I'll bet your spindle bearings are taking a beating. They weren't meant to take that kind of stress. They are axial bearings or tapered roller bearings. Not a good thing to do to them in IMHO.

"Billy G"

Yes, Bill Gruby and if using a chuck to hold the shaft while in that lathe. The chuck ain’t gonna like it either, also IMHO…Good Luck, Dave.

 

[fastback]

You may want to check out Keith Rucker on U-tube. He does some straightening with heat, that may be better way to go about it. He straightened a wood shaper shaft. He quit at .005 I think.

Paul

 

[Smithdoor]

I have use heat be for but that is only 0.005" not good for running shafts

Dave

You may want to check out Keith Rucker on U-tube. He does some straightening with heat, that may be better way to go about it. He straightened a wood shaper shaft. He quit at .005 I think.

Paul

 

[Rbeckett]

I would be concerned that it might crack the tailstock casting where the plunger comes out too. They don't leave a lot of extra material in those parts and it would be a weak link if you put on too much giddy up with the jack.

Bob

 

[Smithdoor]

I did this with 6" and a 1 1/2 ton jack Just a little up and the chisel with one hit of chisel
It was so fast most time it just few try's to fix the shaft

I would be concerned that it might crack the tailstock casting where the plunger comes out too. They don't leave a lot of extra material in those parts and it would be a weak link if you put on too much giddy up with the jack.

Bob