Turning threads off rod fine but now rod advances out of chuck.

[Jim F]

Try shortening the threads before turning the head off.
Head can be seated against the chuck. ?

 

[helmbelly]

Why slit the hex stock at all? Can't you just jam a nut against the threaded hex stock and chuck the hex stock? The nut would go below the jaws of the chuck. Aren't you just trying to immobilize the stud from turning? A steel nut against an aluminum stud shouldn't mark anything.

What is the advantage of the original method? Better concentricity?

good question. A spilt threaded coupling makes a mirror clamp but smaller. clamp it and it usually works to remove the threads from a shaft. I guess as long as the turning pressure from the tool bit does not overcome the clamp force - add more force twisting than clamping and it's bye bye carbide bit. Right? The two locking nuts behind a non split coupling (the other idea) and your pulling the threads back against one wall of the female thread (male thread being on bolt shaft). So I'd say split coupling engages more female/male thread surface - better clamp. Except in my case ;-(

 

[epanzella]

I would start with a pointier cutter to reduce tool pressure. That one look kinda blunt. Sometimes if you can't raise the bridge you lower the river.

 

[helmbelly]

Try shortening the threads before turning the head off.
Head can be seated against the chuck. ?

Not enough meat on the bolt head lengthwise to take the cutting tool w/o deflecting. A 1" bolt, especially brass you can cheat that way but also I like keeping the factory finish on the working end to save repairing it later so I want to strip thread at the bold head end. I'm trying to think if order of operations wise I can cut the head later and use it help prevent the turn- I think there must be an order switch up that can help, thx

 

[helmbelly]

I would start with a pointier cutter to reduce tool pressure. That one look kinda blunt. Sometimes if you can't raise the bridge you lower the river.

Good eyes, that's the 2nd cutter that got trashed. It's now not in the trash but in the 'maybe I can use the shank someday' box next to the trash.

 

[benmychree]

You could make 2 more partial depth slits in the coupling to make it easier to flex for increased holding pressure, besides that what do you call "overtightening" the chuck?

 

[benmychree]

Good eyes, that's the 2nd cutter that got trashed. It's now not in the trash but in the 'maybe I can use the shank someday' box next to the trash.

That is why they make grinders, the tool can be easily ground back and re used.

 

[RaisedByWolves]

Not enough meat on the bolt head lengthwise to take the cutting tool w/o deflecting. A 1" bolt, especially brass you can cheat that way but also I like keeping the factory finish on the working end to save repairing it later so I want to strip thread at the bold head end. I'm trying to think if order of operations wise I can cut the head later and use it help prevent the turn- I think there must be an order switch up that can help, thx

I’m betting you only cut through one side of your fixture and when you turned it down you lost clamping pressure.

I would make a threaded jig mated to the thread pitch, cut through one side fully and half way through the other side.

The half cut on the back side is key, and with the bolt threaded onto the jig you will have tonnes of surface area to grip.

Also, just use HHS for this, no need to ruin carbide toolbits and micro grain is likely to not get you much in this application.

A 5% cobalt toolbit will probably stay sharp for the whole job.

 

[benmychree]

Since there are 3 chuck jaws, there should be 3 cuts.

 

[RaisedByWolves]

Since there are 3 chuck jaws, there should be 3 cuts.

And have 3 pieces?

1.5 is standard for most things with the .5 being referred to as a relief cut.

You’re only looking for about .005-.010 of movement.