Gunsmithing "viper" chambering fixture slippage.

[Ksracer]

I have a large, industrial duty lathe, but the headstock is too long to run a spider on the outboard end. I'm sick of working in the steady rest with a cats head, so I was thinking about using something like the Viper chambering fixture that holds the barrel with 8 set screws in the three jaw, dialing 6" of the breech end in with a grizzly rod, and just letting the muzzle end go wherever it wants inside the headstock. How much danger is there of slippage if I take a heavy cut threading? Any other pitfalls with that setup? Thanks

(Edit) I realize the answer may very well be, "No, you dumb-ass, thats how they were designed to be used", but I just don't see very many people talking about using 1, so I thought I'd better ask.

 

[LRI]

You better be damn sure to control RPM. That bugger is liable to get away from you in a hurry. -cinder block in a washer machine...

Be careful buddy.

 

[Ksracer]

You better be damn sure to control RPM. That bugger is liable to get away from you in a hurry. -cinder block in a washer machine...

Be careful buddy.

There isn't very much my lathe does in a hurry. It's more of a wringer-washer type of machine. About 700rpm is it, but I will definitely be careful. Good advice, Thanks!

 

[Easy_E]

I bought one for the same reason you mentioned. It works I threaded some shorter barrels but IF you take too heavy cuts try parting off some barrel or bump the shoulder while threading mine slipped . My smaller Sheldon lathe chuck jaws dont reach out much so there's alot of material hanging out there.
The plan is to make one shorter with a D1-4 adapter on the end. I have the Bald eagle head bolted to a chuck adapter to get down to a 22" barrel through the head stock and it works great .

 

[300sniper]

You better be damn sure to control RPM. That bugger is liable to get away from you in a hurry. -cinder block in a washer machine...

Be careful buddy.

Exactly what I was going to say. On a manual machine barrel work speeds, probably not much of an issue with less than 20" of unsupported barrel. I wouldn't be doing it with my G50 clamped at 5k.

 

[Gene Poole]

It works, and I've done it, but with all that stick-out, it's tough to get any kind of decent speed and hence and kind of decent finish. Better to remove as much distance as possible. I built similar system, but threaded it so it fits right on the spindle. No chuck so it cuts out at least 8 inches of stick-out and it registers directly on the spindle boss for a solid fit.

 

[cast1]

HSS, light cuts and intermediate spindle speeds.

 

[Terry Cross]

KS,
Look into this: http://www.straightshotgunsmithing.com/page25

This is a precision setup. It is very rigid and holds settings once zeroed. It actually runs best on heavy lathes. Using this, you can zero in the bore of your working end and forget about what the rest of the barrel is doing.

I have one on a heavy manual lathe and it is the bomb.

.

 

[Ksracer]

Thanks guys!

 

[hunter223]

KS,
Look into this: http://www.straightshotgunsmithing.com/page25

This is a precision setup. It is very rigid and holds settings once zeroed. It actually runs best on heavy lathes. Using this, you can zero in the bore of your working end and forget about what the rest of the barrel is doing.

I have one on a heavy manual lathe and it is the bomb.

.

That be a Nardini terry?

 

[Terry Cross]

Yes sir. I would definitely not purchase that lathe if I were getting into the business and buying a lathe dedicated to barrel work.

I got it years ago at a screaming deal at an estate sale where the owner ordered it new and only cut a few aluminum parts on it before letting it sit.

Made in the mid 80s . Very tight and high grade Timken bearings. Very rigid and lots of power but. I modified it heavily and now it is my favorite manual lathe. This pic is it with the TBAS mounted ( actually it never comes off). Super rigid setup on this 3,200 lb lathe.

I have made sleeves for mounting all my blanks via the taper for muzzle work as well.

I would be scared poopless of that long fixture running at any RPM not to mention being limited to super light cuts. etc..

 

[hunter223]

Yes sir. I would definitely not purchase that lathe if I were getting into the business and buying a lathe dedicated to barrel work.

I got it years ago at a screaming deal at an estate sale where the owner ordered it new and only cut a few aluminum parts on it before letting it sit.

Made in the mid 80s . Very tight and high grade Timken bearings. Very rigid and lots of power but. I modified it heavily and now it is my favorite manual lathe. This pic is it with the TBAS mounted ( actually it never comes off). Super rigid setup on this 3,200 lb lathe.

I have made sleeves for mounting all my blanks via the taper for muzzle work as well.

I would be scared poopless of that long fixture running at any RPM not to mention being limited to super light cuts. etc..

Pic isn't showing up buddy