Barrel Holding in Lathe chuck question
- Thread starter blade-57
- Start date
- Location
- Manitoulin Island
Have used strip of copper. Cardboard doesn't grip very firmly. Assume you are chucking in 3-jaw. Strip should be as wide as jaws for good grip. If strip is too thin it can cut through if work slips. Be careful.
Use a four jaw chuck and a spider on the other end. You need to get the bore at the muzzle end indicated less than a thou out and the breech end as close as you can. Just grabbing it in a chuck is not the way to do it...
You can protect the barrel with pieces of brass rod as shown in this picture of chambering and threading a dialed in bore. Lousy chamber finish due to faulty reamer not ground properly. It did polish up fine. Reamer went back to manufacturer.
You can protect the barrel with pieces of brass rod as shown in this picture of chambering and threading a dialed in bore. Lousy chamber finish due to faulty reamer not ground properly. It did polish up fine. Reamer went back to manufacturer.
Last edited:
Being an "epoxy fixes all" sort of guy this is what I do. I use moulded epoxy bushings for my barrel vise so I mould one close to the muzzle end and when hard put the barrel between centres and turn the epoxy blob round and true. I then grab the blob in the set-true and centre up and ready to go. When finished it will hammer off especially with any barrel taper but for this job don't take it off until finished because it won't go back exactly the same. Nothing is spinning too fast so this in normally all the support needed, If I think I need some I will put some sort of extension on the barrel to get to the spider, my lathe is 16x60 so has a fairly long headstock.
I use a piece of clean, unoxidized zinc flashing to protect the barrel from the chuck jaws. I also support the barrel with a steady rest on the breach end after setting up while between centers. That means that the breach end is supported concentric with the bore and the piloted reamer with a center hole at the shank end is supported by the center in the tail stock and therefore guided in centered in the bore.
cheers mooncoon
cheers mooncoon
touche; you are right :>( In that case I would just protect the breach threads with zinc flashing and support the muzzle with a live center. My lathe is a Myford super 7 and only has a 5/8 hole in the headstock, so I have to do threading and chambering with the barrel outside the headstock. On the other hand, as long as my tailstock is accurately centered, it ensures threading or chambering is concentric to the bore
cheers mooncoon
Is it not a bad idea to put any type of centering tool in the muzzle?? You would be better off dialing in with a steady rest and precision ground pin in the bore. I'm just a machinist not a gunsmith so, .02 worth.. Guys with access to lathes with too long of headstocks have this same issue, so I am very interested to hear a solution also.
Use a four jaw chuck and a spider on the other end. You need to get the bore at the muzzle end indicated less than a thou out and the breech end as close as you can. Just grabbing it in a chuck is not the way to do it...
You can protect the barrel with pieces of brass rod as shown in this picture of chambering and threading a dialed in bore.
How in the hell do you get all that lined up in the chuck? You'd need about 4 hands to get all those little bits in the right place all at the same time. :O
The thing you aren't considering is having to work on a piece without marring the exterior finish. A ready rest is going to destroy the bluing or whatever finish is on the outside of the barrel. So a steady rest is a non-starter for this kind of work.
You center it on a live center while dialing the the spider at the other end... the spider then holds that end... then while it is still on the live center hold a brass pin in place and lightly tighten one jaw on it, repeat until all four are in place, then back the live center away and dial the bore in to the closest 10 thou you can.
Guntech's method is a good one. I used to do the same thing.
Now, I just wrap the part of the barrel I want to hold with heavy gage but still pliable brass shim stock. I follow the rest of his method though.
Now, I just wrap the part of the barrel I want to hold with heavy gage but still pliable brass shim stock. I follow the rest of his method though.
