Outboard Spider

[Tozguy]

Okay, neat idea.....But how is that outboard chuck mounted?
If by (right-handed) threads it seems to me it would really want to unscrew, especially during spin-up.....but I guess having it grip the same item that's in the in-board collet would help that.
Thanks,
-brino

Yes that is right, the inboard spider (or chuck) holds the work from turning so there is no torque on the outboard spider. The outboard spider is only for locating the barrel wrt the spindle axis and only enough pressure should be used on the screws to accomplish that. Any additional pressure added with the intent of 'holding' the barrel from turning can be counterproductive.

 

[Coomba]

My previous posts pictures were a little misleading...I just threw a barrel in to show the relationship between the two chucks . Here is actually my barrel spider setup w/rangerod and indicators. No need for a outboard spider

Yup, that’s what I was taught on.

 

[JoeC]

My previous posts pictures were a little misleading...I just threw a barrel in to show the relationship between the two chucks . Here is actually my barrel spider setup w/rangerod and indicators. No need for a outboard spider

Hi, Joe here, pretty new to machining.
So with the barrel in the inboard spider, wouldn't you still want the other end of the barrel in an outboard spider to keep it from whipping around?

 

[Tozguy]

Joe, my barrel work is done at 65 rpm. I would not be concerned about a 1.25'' diameter pipe whipping around at that speed especially if it is carefully set coaxial to the spindle axis to start with using Buffalo's set up.

The idea of extra outboard support might still be good idea especially for longer thinner barrels, say 30'' or more, so am looking forward to reading what Buffalo does.

 

[Bamban]

My previous posts pictures were a little misleading...I just threw a barrel in to show the relationship between the two chucks . Here is actually my barrel spider setup w/rangerod and indicators. No need for a outboard spider

How long is that cathead? What is the spacing between the 2 sets of screws? How is it mounted on the plate, welded, bolted?

 

[Buffalobull]

Hi, Joe here, pretty new to machining.
So with the barrel in the inboard spider, wouldn't you still want the other end of the barrel in an outboard spider to keep it from whipping around?

Joe, my barrel work is done at 65 rpm. I would not be concerned about a 1.25'' diameter pipe whipping around at that speed especially if it is carefully set coaxial to the spindle axis to start with using Buffalo's set up.

The idea of extra outboard support might still be good idea especially for longer thinner barrels, say 30'' or more, so am looking forward to reading what Buffalo does.

Tozguy pretty much summed it up. turning at a low rpm there is not much of a chance for whipping. It takes at least a 30" barrel to even make it to the lathes original spider and if it does make it I just snug them up , I don't want to put any pressure to the dialed in barrel axis so the outboard chuck I have is not used. The overall length is approx. 11" including the D1-5 plate and the bolts are 4 3/4" apart

 

[Buffalobull]

In my original post I mentioned using the outboard chuck for barrel work. These pictures should shed better light on that setup. I made a special set of jaws for holding tapered barrels (pic 1).... I utilize the outboard chuck not only to center the barrel but also to hold it from pushing back when turning and threading mainly for muzzle breaks and when crowning the barrel (pic 2). Due to the small thru hole of the chuck I do have to make adapters to hold the chamber end of the barrel (pic 3)