Bead roller dies used on Lathe ??

[Ringo]

Has anyone tried useing bead roller (tubing) dies on a lathe?
I'm thinking along the lines of knurling tool and replace the knurl wheels with bead and cove wheels.
perhaps the bead die is in the chuck, and cove the wheels
Anyone?

[nc5a]

I've never tried what you proposed but can think of several problems you will run into. Speed of the driven die, adjustment of clearances, work envelope, physically managing the material you are beading, reversing the driven die rotation just to name a few. That being said there are metal spinning operations that produce a bead profile so I guess it will depend on what exactly you are wanting to bead.

Give it a shot and let us know the good, bad and ugly.

[Tobias-B]

Sure, why not?
I agree with NC- there are some cases (like with tubing) where it may be a great idea,
and others where it's less so.

t

[reggie_obe]

The downside?
Lack of control of the strip of metal to be rolled, beaded, flanged. Can't stop the lathe spindle as quickly as you stop a hand cranked roll.

[BCRider]

Rather than using the tail stock in my mind's eye I'm seeing a specialty tool post "block" that replaces the tool post altogether. That way it can use two bolts into the T slot plate for more rigidity. There would be one roller on it that is fixed and a second that moves horizontally on it's own dovetail or other way with a sturdy pressure screw.

For an inward shape bead the roller with the depression would go on the fixed stud and go inside the tubing. Then the outer roller would form the metal inwards with the screw. For an outward shaped bead the fixed roller with the depression would go on the outside on the back of the tube away from the operator and the movable roller on the ID and push the metal outwards into the fixed roller.

The only requirement is that for inward shapes the fixed roller that is used for the ID would need to be small enough to be removed through the reduced ID. Or the shaft with the roller could be released and allowed to fall through and out the other end?

If made sturdy enough the moveable roller could be on a swinging arm rather than a dovetail or other machined way. That might be easier to make. Since it's not a cutting operation there's no reason why it can't move in an arc into the work. And that style would actually be easier to make for anyone without a big monster of a dovetail cutter.

On the other hand if it's for a thin enough material there's no reason at all why it could not be done with a fixed die in the tail stock as mentioned. Ideally it would use a live center that uses fairly easily changed points so a new shape can be made and inserted. The downside with a live center for the ID is that you can't push outward. Only use it for fixed rollers for inward shapes. A purpose made tool would permit forming inward AND outward.

[BCRider]

Powered vs hand cranked..... One could simply use the chuck key as a hand crank if the tubing is a thin enough wall. Or if worried about it a large adjustable wrench on the jaws. If a collet chuck is being used then perhaps as part of the project to make such a forming tool also make up a hand crank with an expanding arbor that fits into the outboard end of the spindle. As long as it's not a really big lathe it's not too hard to reach over and run something like that with a hand crank. On lathes that are 12 inches swing and smaller at least.

[Ringo]

use the chuck key as the hand crank.....I like that

[BCRider]

For thin wall or very soft wall tube? Sure! Of course if you need more than some reasonable torque then it would not be a good idea. But then if it was that resistant to accepting the bead then it's the wrong tubing or too aggressive a forming operation in the first place.

[Ringo]

3" 304SS .065 wall tube

[BCRider]

That size would permit a fairly stoutly built setup. Which is a good thing since I'm fairly sure it will require fairly high pressure. More than knurling for sure. I'm not sure I'd want to put that much pressure into my cross slide lead screw. So the beauty of my tool post position idea is that there's no load taken by the lathe itself other than the torque from turning the tubing. And I think that in back gear and with a smooth amount of torque on the clamping screw it would form your bead or other shape in something like a dozen turns or so... provided that form of SS doesn't work harden. If it does there might be a mid forming annealing needed.