Turn Off Lathe Backing Plate...Tips?

[G-ManBart]

To prevent a lot of future chuck sticks, cut a washer out of parchment (best) or wax paper (good) 2-3/4" OD by 2-1/4" ID and place it between the chuck and the spindle shoulder.

This washer won't help if you jam on a chuck with swarf in the threads, but if it is just spun on too tight, it will prevent any metal to metal seizing.

Thanks...I was planning on doing that. I haven't had a stuck chuck before and I sure don't want to have one again!

 

[G-ManBart]

They give so much more love than humans, that's why their lives are so much shorter....

Absolutely true! His younger brother is looking at me right now...it seems I'm 20 minutes late for our usual handful of pretzels snack

 

[matthewsx]

Did I ever tell you my dad lived in Belleville as a kid?

 

[G-ManBart]

Did I ever tell you my dad lived in Belleville as a kid?

Nope...small world!

 

[mattthemuppet2]

Aww, I'm sorry to hear that.

As for the locking bar, I'm pretty sure they other guy went through the same thing. His solution was to bore out a piece of steel to the diameter of the spindle and make that into the clamp.

 

[G-ManBart]

Aww, I'm sorry to hear that.

As for the locking bar, I'm pretty sure they other guy went through the same thing. His solution was to bore out a piece of steel to the diameter of the spindle and make that into the clamp.

Thanks...it's never easy, but we got a lot of great years out of him!

I first tried a split collar bored to size, but it slips. I have considered making another with a bigger gap between the two halves. Now when I tighten it down the two halves are almost touching...like really close so it may not be tight enough to really lock it. I'll try that if the gear block doesn't work.

 

[mickri]

From what I am reading from the other posts you need to load up the lever with a 100 lbs or more and let it sit for a couple of days with a daily whack or two with a BFH on the backing plate at the threads. Patience will prevail. Don't be in a rush.

 

[G-ManBart]

From what I am reading from the other posts you need to load up the lever with a 100 lbs or more and let it sit for a couple of days with a daily whack or two with a BFH on the backing plate at the threads. Patience will prevail. Don't be in a rush.

That does seem to work for many people, but not always from what I can tell. At this point I have to get the spindle locked better or nothing will work. I'm not in a rush, so I'm just trying to work through it methodically.

 

[SLK001]

That does seem to work for many people, but not always from what I can tell. At this point I have to get the spindle locked better or nothing will work. I'm not in a rush, so I'm just trying to work through it methodically.

This usually works for chucks just spun on too tight. If the chuck was forced on with swarf in the threads, that is a different story.

 

[G-ManBart]

I always find it a major letdown when there's a thread like this and people don't follow up, so here's an update.

Success! The gear block showed up today so I popped it in, then gave a good pull on the extension bar, but nothing happened. That had me a bit worried, but I lifted myself off the ground with the long bar (3.5ft give or take) and after a second or two I was thinking I would have to load the bar up and wait but then it popped loose. I figure that was something like 6-700 lb/ft

The threads on the spindle were clean and didn't seem to have any rust or swarf stuck in them. The threads on the backing plate had some dried crud that I'm guessing is cutting oil, but not much else. I sprayed the backing plate threads with brake cleaner and then ran a dental pick through them to get all the dried grit out and I found two tiny little spots that I'm guessing were pieces of swarf that got rammed in there at some point and created high spots. I ran the pick over them a few times and got most of them out, but I'll probably have to do a bit more. I spun the plate back onto the spindle and it was smooth but did lock up tight right at the last second even just spinning it by hand. I'll clean the backing plate threads a bit more and plan to use a washer behind it just in case going forward. I actually bought a new chuck so I would have one with reversible jaws, so I may not even use the old chuck going forward.

The good news is I was finally able to check the runout on the inside of the spindle nose (part of why I was going to remove the chuck in the first place) and I'm very happy with the results so this was a win-win.

Thanks to everyone who offered suggestions!