I'm relieved but have a question

[Haynie]

Head and tail stock were not aligning. This means when I brought the tail stock up to the three jaw chuck the tail was off a bit. I finally found an allen wrench stubby enough to get behind the chuck to remove it from the plate. I slipped the dead center into the MT, crossed my fingers and brought the live center up to it. Perfect match!

So it is my chuck that is out of alignment. It is a three jaw self centering chuck and I am assuming it needs to be taken apart and cleaned. Is this possible? I should probably replace the jaws too if they look worn right?

 

[BKelley]

How much off ? Have the jaws ever been off the chuck? Were they put back on in the proper sequence? It is hard to find a dependant three jaw chuck that is absolutly dead on.

Ben

 

[Rich L]

I love pictures - what kind of lathe? That might not matter - how does your chuck bolt to its backplate if that's what you have. Is there sliding around room to re-center or is there a registration recess between the plate and the chuck.

How much is a bit? Yeah, I know:12.5 cents

If it's just a little bit and the closure is repeatable, bore the chuck jaws in place.

Cheers,
Rich

 

[Penultimate]

I took the jaws off my chuck once and when I reassembled it there was a lot of runout. The jaws are not interchangeable, check that the numbers on the jaws and match the numbers stamped in the chuck.

I marked the position of the chuck to the back plate so it always goes on in the same position. I also tighten in the same key location.

 

[rherrell]

I took the jaws off my chuck once and when I reassembled it there was a lot of runout. The jaws are not interchangeable, check that the numbers on the jaws and match the numbers stamped in the chuck.

I marked the position of the chuck to the back plate so it always goes on in the same position. I also tighten in the same key location.

This may sound crazy but it works. Take a sharpie and mark your key holes 1,2 and 3, tighten 1 and measure the runout, then loosen it and tighten using 2, and then 3, I'll bet one location is better than the others. Mark your key location somehow so you can tighten it using the same location all the time.

 

[Haynie]

Thanks so far.

Had to get out of dodge for a couple of days. Would have been a great trip if it were not for 2 days of hellish wind.

I will get some pictures.

 

[KenV]

Mark -- some three jaw chucks are intended to be machined out to the approximate size of the work to be used. I am reading you post as having the 3 jaw chuck on a wood lathe ---

Lots of variables with 3 jaw machinist chucks -- strengths and well as weaknesses.

Because of the limitations, many move to 4 jaw scroll chucks -- but knowing the limitations, they can do some excellent work.