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carbide tipped half dead center

You can get them on ebay fairly reasonable

I use a dead center to center the bore of the gun. Then, I use live centers for turning the OD to the major diameter & keeping the tap/die straight with the piece while keeping the tailpiece tensioned well enough to hold the tool straight.

It's generally easier for me than taking the lathe apart and changing gears on my small lathe.

Though anyone will admit that single point threading is better.

Someone makes a spring loaded center tool so you don't have to constantly be turning the tailstock in every half turn or so.

I'll also add, you don't have to use the tool the entire depth of the thread either. Once you have it about a 1/4 threaded, it's as straight (or crooked) as it's going to be.

I read it twice...but I must be missing something here...maybe I'm missing a lot here. Remove chuck install Dead center in spindle bore on the breech end, lathe dog, live center in muzzle, single point the thread....done. Die is a recipe for non alignment and non concentricity..and what is with the half center?...do you need to recut the muzzle face? I must have missed something.

Your single point cutter goods will contact your live center goods, iirc.


Dinny,

Did similar to this lately on a barreled action. Muzzle on a live center. Turned down muzzle diameter a ways just for tool clearance. It was less than thread minor. Then threaded back from there. Then cut to length and did the crown with my Manson hand tool. All I could think of at the time. It worked but I had the extra barrel length and the Manson 11° tool.

Half dead center... Hmmm....

We are just cutting a simple male thread on the muzzle for a can or a brake...right? Why in hell would the 60 deg single point threading tool bit even get within a 100 thou wall thickness of the bore where the live center is seated? Am I going nuts? Is this something other than the simplest of operations...cutting external threads between centers?

LOL

Not the cutter's business end hitting the center - inside the bore. It's "side" hits the center outside. When the angle of the dangle conflicts with the doodad - you see?


Maybe he, like I, was using an indexable tool... Whereas you picture a straight HSS tool?

LOL


FL,

This type of a setup would work, I figure you mean this....

But my external thread cutter, with a three-tipped insert was positioned where the tool would contact the center, before reaching the work....

My tool is like this. I can see where having a petite HSS threading tool would be better here.


A long (extended) nose live center would help.


Or a half dead center as suggested.

A 1/4" or 5/16" 60 degree v thread cutting tool is cheap , or you can grind one from HSS bar stock. The Insert type holders are too big for close in work near a Live center.

Exactly correct Moose...what Mtn Boomer should be doing is the old skool setup shown in the upper page here...except the 1/4" 60 deg threading point should be mounted upside down, the lathe run in reverse and cut the threads AWAY from the inner shoulder TOWARD the muzzle. Thereby avoiding a crash and also leaving a clean precise shoulder for the brake or can to index up to dead flat and tight.

Have to hear from Dinny if that was his situation prompting this thread - tool clearance - seems like it was. The half center might be all it takes too.

I'm pretty cool with through the headstock, threading toward the shoulder, living on the edge! And cutting the crown then too as I have been learning. Recently got some advise on making an internally threaded gauge to fit to also. Pretty fun machine. Definitely interesting the many many things to learn.

Well I always cut my shoulder clearance area just slightly deeper than My thread depth will be . I use Back gear so slowly cutting , and a 2-3 threads width clearance and a quick hand stopping the carriage and you wont crash a bit or have to cut threads in an Unconventional way. This doesnt hurt a thing and the attachment screws up tight. I would rather have my cutter heading away from the muzzle and live center and makes it easier to use the compound rest . Its much easier to dress up the seat face of the barrel to 90 Deg. after threading . Old School Baby !

Here is what I use for threading Barrels and shafts, bolts , etc.





I grind my own tooling for Acme Threads etc. since you may not find them for sale...
Rich

Here is another trick , undercut the minor diameter at the muzzle by .010 for clearance and then start the threads to the shoulder length needed.


This is an exaggerated example to show as it can be done at the muzzle as well.
Rich

The half dead center even allows some face work. I like the Warner tool high speed.insert tooling for most barrel threading. I recently got a carbide one for 55⁰ whitworth threads and running the spindle at 180 rpm it yielded good finish. It is full profile 12 TPI cutter.

Make your crown saver long enough that the tool will have clearance from the center. About a 1/2" proud of the muzzle should be plenty. I prefer to make them from brass. A piece of 3/8" or 1/2" round brass stock should do it. Then lathe cut your threads. The whole job would probably take about 30 minutes.

I would never use a dead center in any bore that mattered. Buy a live center that you can turn down to about 1/2" diameter or just get one that already is and you're set. There are plenty of single point carbide indexable holders on the market that work very well. I have one that holds the tool vertically and have machined some of it away. The tip extends enough that on a rifle barrel, unless it's a heavy contour, it can be turned upside down and ran away from the shoulder.
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In re-reading this, it seems like his main issue was how to center the breech end of the barrel. First choice would, of course, be to remove the barrel from the receiver. Choice number two would be to use a mandrel in the action. Alignment would not be perfect (without considerable luck) but should be OK. GD

I've threaded a number of barrels on rifles that have already been fired and have a known accuracy. The dead center has had zero effect on accuracy. A prominent Arizona gunsmith turned me onto this method. I haven't found a simpler way of doing it.

As far as the beach end. I've threaded/ crowned a few that couldn't be removed from the action by grabbing the action with a 4-jaw and indicating the outside of the barrel at the front of the action.

Wow. This grew into something way different than I ever imagined it would become. I was taught to indicate the muzzle true and round by inserting a gauge pin in the bore rather than indicating off the barrel OD. All I wondered was how to get the barrel indicated true round when the live center (and an aluminum extension) are stuck in the barrel and I turned it on the live center.