How did this happen? Bent gear shaft...

WobblyHand said:
Is there another retainer besides the set screw and nut?
Click to expand...
I'm not familiar with that lathe . There has to be some sort of retainer to keep the gear assembly in place. though. On my lathe, there is a screw and washer threaded into the shaft from the outside. My hand wheel is pinned but you shouldn't need to remove the hand wheel and its gear to remove the bent assembly.
 
What kind of lathe is it.

fwiw....bent shafts sometimes can be easily fixed by heating until it just begins to turn blue. Mount the shaft in v-blocks. Mount with high spot pointing upward. And locate the high spot pointing upward directly under a press. An arbor press would be ideal but I’ve used a hydraulic press on the last two I did.
So heat it till it’s blue. I used two small portable plumbing propane torches. Once it just discolors to a blue tinge....and we’re only aiming for the bent area to be blue, not the entire shaft. Use the press to then straighten the shaft.
FWIW....It seldom is going to come out perfect. But, what you will have is a fairly straight shaft. In your case, you’ll have a shaft in which will allow you to take measurements of the shaft.....then put the lathe back together.... and then use the lathe to make a replacement. It may come out good enough to forego making a replacement. I’ve had good luck doing a couple shafts like this. Now I’m not talking about large diameter shafts like the boat driveshafts Kieth Fenner straightens. I’m talking about shafts like you have there. About 1/2” diameter.
 
There's probably a taper pin there somewhere holding that
 
Hand wheel didn't want to come off because of this.
IMG_20200708_180907.jpg
Yes that is a gouge. The real dimple is present as well. I didn't do that. The gouge, that is.

Now to remove the bent shaft. Tried using a punch. Nope, going to need an arbor or something like that.
IMG_20200708_180925.jpg
 
Tim9 said:
What kind of lathe is it.

fwiw....bent shafts sometimes can be easily fixed by heating until it just begins to turn blue. Mount the shaft in v-blocks. Mount with high spot pointing upward. And locate the high spot pointing upward directly under a press. An arbor press would be ideal but I’ve used a hydraulic press on the last two I did.
So heat it till it’s blue. I used two small portable plumbing propane torches. Once it just discolors to a blue tinge....and we’re only aiming for the bent area to be blue, not the entire shaft. Use the press to then straighten the shaft.
FWIW....It seldom is going to come out perfect. But, what you will have is a fairly straight shaft. In your case, you’ll have a shaft in which will allow you to take measurements of the shaft.....then put the lathe back together.... and then use the lathe to make a replacement. It may come out good enough to forego making a replacement. I’ve had good luck doing a couple shafts like this. Now I’m not talking about large diameter shafts like the boat driveshafts Kieth Fenner straightens. I’m talking about shafts like you have there. About 1/2” diameter.
Click to expand...
Just a 7x16 mini-lathe that I bought from LMS.
 
Here’s a photo of it. Hard for me to tell....but I’m guessing it’s either set screws or an interlocking mechanism. I see there’s a ball there too. And it’s going in from the far side of where your shaft is. But from the looks of it, your may have something similar as what’s in the pic. Set screws into side of housing holding shafts.
 

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My bad....just looked at it again and those three screws are for your gib. Then there’s another with the spring and ball which is for a detent.
 
Have parts on order. LMS is throwing in a new gear assembly gratis. :) Still need to find a way to press the shaft out. Wheel pullers don't work very well if the arms are asymmetric. Would a cheap 1 Ton arbor press work?
 
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