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Brad Simmons
08-06-2013, 10:19 AM
The threads on my Delta 46-460 lathe spindle are slightly damaged. *Someone* tried to remove a face plate without disengaging the set screw. As a result, I can't get a chuck all the way on so it engaged on its back side. Is it repairable with a round die? Is this advisable?

Tim Fulford
08-06-2013, 10:29 AM
You can get thread restoring files our use a swiss file (needle file) in most cases. Worse case scenario is new spindle!

Brad Simmons
08-06-2013, 10:42 AM
Definitely trying to avoid the worst case. I've never seen those thread files before. Thanks!

Sid Matheny
08-06-2013, 1:16 PM
I would get one of the cheaper thread files for that.
268050

Sid

Richard Jones
08-06-2013, 3:47 PM
I'd try a small saw file if you have one, just cut enough off to smooth up the burrs.

Not that I've ever had to do it..............................:eek:

Kyle Iwamoto
08-06-2013, 5:21 PM
The smallest triangle file from the big box stores works also. Not that I ever did that.

As a result, I have found that as long as you seat your chuck or face plate well, there really is no reason to use that grub screw. You can sand in reverse with no problems. Seat the chuck firmly, and you could do turnings in reverse. Oh, don't use that plastic washer that prevents the chuck from getting stuck. You want your chuck firmly seated. Lessens vibration.

Peter Fabricius
08-06-2013, 10:16 PM
OK, so it happened to me!
I just cleaned up the threads with a small triangle file. No problem.
hope it works for you
Peter F.

robert baccus
08-07-2013, 12:35 AM
All good advice--a proper file should do it. Also I agree with the no plastic washer--buy a can, at any auto store, of thread anti seizing compound. Prevents locking up and lubes the threads. Machinest's love the stuff.

David C. Roseman
08-07-2013, 7:40 AM
[snip]
As a result, I have found that as long as you seat your chuck or face plate well, there really is no reason to use that grub screw. You can sand in reverse with no problems. Seat the chuck firmly, and you could do turnings in reverse. [snip].

There has been discussion of the grub screw issue for reverse turning elsewhere, and some would disagree strongly with this, especially with heavy bowls. May not matter with this particular Delta lathe. I've had a heavy bowl start to unspool on a larger lathe. It was stopped by the tool rest, fortunately.

David

Dan Hintz
08-07-2013, 8:09 AM
As a result, I have found that as long as you seat your chuck or face plate well, there really is no reason to use that grub screw.

I'd suggests against not using one if you turn in reverse. You're counting on friction to save you, but when it comes to something heavy, you want a mechanical advantage, not just friction. At a minimum, a heavy chuck will ding your bed badly... at worst, you'll have a heavy wood/metal object flying at you. And I know I can't duck that fast.

Kyle Iwamoto
08-07-2013, 7:19 PM
I wouldn't turn large items in reverse either. I meant small turnings, and sanding.

Jeffrey J Smith
08-07-2013, 11:40 PM
I'm with Dan on this one. Sanding large diameter pieces, or just heavy pieces in general in reverse is what the grub screws are there for. I switched to brass tipped set screws from McMaster-Carr after buggering up the threads on my old Jet lathe (spindle is definitely NOT hardened steel); I've also seen a chuck unscrew itself during demos (twice). Bought enough for all my chucks - cheap insurance, and won't damage the threads in case you forget...