Which 4 Jaw D1-5 chuck for chambering?

[LVLAaron]

Just placed an order with Precision Matthews for a lathe (1440GT) and a bunch of accessories.

The only obvious (to me) thing I wasn't able to get was a 4 jaw chuck.

Looking for the advice of the experienced what I should be looking to procure.

 

[parshal]

I use a set-tru 3-jaw for chambering on my 1340. I have a 4-jaw but never use it.

 

[Ken226]

If you intend to run the muzzle end of the barrel blank in the chuck, and the chamber end in a steady rest, it won't matter much. Any decent quality 4 jaw independant, or set-tru style 3 or 6 jaw scroll chuck will work. I've finished many barrel blanks that way.

That said, lately I've been going with a set of 4-screw spiders. One on on the spindle nose and one on the back of the spindle. The job seems to go quicker and easier that way.

I have several that I made for various similar purposes.

This is my front and back spider, for cutting / threading tenons and chambering.



My backside spider threads directly into the spindles preload nut threads.



If you look at the specs of the lathe you ordered, you may get lucky and find it already has an integral rear spider.



This is a spider chuck I made for truing receivers and bolts. I could easily chamber barrels in it as well.



If you don't want to make one, grizzly sells a pre made, d1-5 direct mount spider. You'd probably have to fabricate the rear spider.

Gunsmith D1-5 Back Plate without Guard - Grizzly Industrial

The Gunsmith's Back Plate has "spider" supports machined into them, which allows shorter barrels to be supported through the headstock of larger lathes. D1-5 type without guard.

www.grizzly.com

 

[Tozguy]

What Ken said!
I used a four jaw at first for chambering barrels but then made up a spider as many others have done.
A front spider brings the cutting closer to the spindle bearings and allows for holding somewhat shorter barrels when compared to any kind of chuck.
You are still in need of a 4 jaw for other purposes but there are no special considerations with respect to barrels.

 

[7milesup]

If you intend to run the muzzle end of the barrel blank in the chuck, and the chamber end in a steady rest, it won't matter much. Any decent quality 4 jaw independant, or set-tru style 3 or 6 jaw scroll chuck will work. I've finished many barrel blanks that way.

That said, lately I've been going with a set of 4-screw spiders. One on on the spindle nose and one on the back of the spindle. The job seems to go quicker and easier that way.

I have several that I made for various similar purposes.

This is my front and back spider, for cutting / threading tenons and chambering.



My backside spider threads directly into the spindles preload nut threads.



If you look at the specs of the lathe you ordered, you may get lucky and find it already has an integral rear spider.



This is a spider chuck I made for truing receivers and bolts. I could easily chamber barrels in it as well.



If you don't want to make one, grizzly sells a pre made, d1-5 direct mount spider. You'd probably have to fabricate the rear spider.

Gunsmith D1-5 Back Plate without Guard - Grizzly Industrial

The Gunsmith's Back Plate has "spider" supports machined into them, which allows shorter barrels to be supported through the headstock of larger lathes. D1-5 type without guard.

www.grizzly.com

That is quite the spider Ken. Looks like you made the rear one with a CNC to get your engraving on it?
Two questions...
1.) I am surprised that the bolts with the anti-mar heads provide enough "grip" to keep your work for slipping in the spider. I have no experience with spiders, so there is that.
2.) What flavor of metal did you use to make the spiders? I would assume it is not 1018.

Thank you

 

[Ken226]

That is quite the spider Ken. Looks like you made the rear one with a CNC to get your engraving on it?
Two questions...
1.) I am surprised that the bolts with the anti-mar heads provide enough "grip" to keep your work for slipping in the spider. I have no experience with spiders, so there is that.
2.) What flavor of metal did you use to make the spiders? I would assume it is not 1018.

Thank you

That one is a direct mount d1-4 action truing chuck. I used a Shars d1-4 back plate and a 4-3/4" chunk of 8620 I picked up on ebay for 50$. For this purpose, 1018 would be fine. The commercial viper fixture is made of aluminum, and works fine.

The only thing I used a cnc for was the engraving. Everything else was done on my lathe and my PM935 manual mill.

The brass tip screws provide plenty of grip. I've never had one slip. When I indicate the bore, I adjust it with Allen keys in opposing screws, simulteneously loosening/tightening until within about .005", then finish up the last few thousandths by adding torque to the high sides. It ends up fairly tight when dialed in. I've never had any slipping issues.

I used a 2" facing mill to cut the flats. After the first cut, I just flipped it in the vice, using parallels and angle blocks to index for the other flats and screw holes.

The rectangular slots for bolt handle clearance were cut with a 3/8" carbide end mill. I just tracked out the same rectangular path over and over, using .1" depth of cut increments until all the way through. It's 3/4" wide, so a 3/8" step-over. Though I may need to widen it to 1".

 

[7milesup]

Awesome. Thank you for the response Ken.

 

[springer]

I use a homemade spider on front and back as well. Almost identical to the grizzly unit. My front is made from a backplate and aluminum. The rear is just slip fit to the spindle and made from 1018, been working well for several years, never even had to replace the screws.

 

[Ken226]

One of the things I found to be a pain in the butt on my lathe, was indicating the barrel on the backside. My lathe's gear cover is fiberglass, and the top of the headstock has a polyurethane mat glued on. I had a pretty small area available for attaching a magnetic indicator base.

I made a decent looking cerakoted steel plate, and attachedi t to the fiberglass cover with some socket heads screws and nuts.



I had a pint of cobalt cerakote that was about 3 years old. I cerakoted all kinds of parts on my lathe just to use it up before it went bad. I even cerakoted the entire headstock top cover.

 

[7milesup]

^^^ very nice. Did you use a laser to etch the words on the plate?