Spiders Rule, 4-Jaws Drool

[LVLAaron]

I have a gorgeous Buck 6 jaw set-true. Dialing a barrel with it is a tremendous pain. It's much easier to dial something in a 4 jaw than it is a set-true.

 

[butchlambert]

I sent my 6 jaw Tru Adjust to Alan Warner. Way to heavy for this old man. I've used 2 spiders from the get go.

 

[Dusty Stevens]

I have a gorgeous Buck 6 jaw set-true. Dialing a barrel with it is a tremendous pain. It's much easier to dial something in a 4 jaw than it is a set-true.

Lemme get that.

 

[LVLAaron]

Not a chance in hell haha. It is an amazing chuck and if I'm doing non-barrel work it's my go to. It's so pretty I almost hate using it.

 

[INTJ]

I admire all of the inventive ways fellow craftsmen come up with to dial in barrels.

But strictly from a Machinist point of view, wouldn’t a Set True Chuck be a more practical option?

If they, once set, would hold everything to .0002" then they would be great. But from what I understand, they require continually adjusting to get that level of accuracy every time a new barrel is put in.

And if so am going to have to adjust for each barrel, the spiders are the fastest way, at least for me.

 

[Dusty Stevens]

If they, once set, would hold everything to .0002" then they would be great. But from what I understand, they require continually adjusting to get that level of accuracy every time a new barrel is put in.

And if so am going to have to adjust for each barrel, the spiders are the fastest way, at least for me.

The best thing about a set tru chuck is you dont have to loosen the jaws to adjust it and the 6 jaws hold better without more pressure. Yes you must dial in each time and you do it with a hex key just like a spider. Its not much different at that point except not having to re-do soft tips in your adjustment bolts ever again

 

[WSnyder]

I have no problem adjusting my 6 jaw set-tru. Once you get used to it it's no big deal and no harder than using my 4 jaw. It's a bit of a mind warp at first with the opposite action of each but once you learn it's fine or it is for me.

 

[Carl S]

Set true and true bore system are good.with the spider your close to the head stock bearing,less deflection,depending on the design of your spider..closer the better for me.do what's best for you and gives you correct-consistent results.

 

[Walt Krafft]

If they, once set, would hold everything to .0002" then they would be great. But from what I understand, they require continually adjusting to get that level of accuracy every time a new barrel is put in.

And if so am going to have to adjust for each barrel, the spiders are the fastest way, at least for me.

It is the bore of the barrel that needs to be dialed in. Rarely are they in the center of the blank. I find dialing in with the set true type chuck way faster than a 4 jaw. Once chucked, the part always stays tight.

 

[INTJ]

It is the bore of the barrel that needs to be dialed in. Rarely are they in the center of the blank. I find dialing in with the set true type chuck way faster than a 4 jaw. Once chucked, the part always stays tight.

Well I know that I always dial in the bore, not sure about everyone else....

If I understand it right, the set screws on the set true move the part after it's dialed in. But if they are not tightened then the chuck will move. How do you deal with that?

 

[Dusty Stevens]

Well I know that I always dial in the bore, not sure about everyone else....

If I understand it right, the set screws on the set true move the part after it's dialed in. But if they are not tightened then the chuck will move. How do you deal with that?

Ive never touched the front screws that lock it down and the outside ones that actually move it work exactly like a spider and stay tight

 

[INTJ]

Which set true do you like?

 

[Dusty Stevens]

Buck or bison for me

 

[Walt Krafft]

I slightly loosen the screws that hold the chuck to the mounting plate. Dial the bore in, tighten the mounting bolts, give it another spin to make sure it is still good. Usually get 0.0001 tir. My max is 0.0002. I have seen bore runout of 0.010 tir when going from one barrel to the next.

 

[Walt Krafft]

I use a Buck. Bought from Hardinge.com.

 

[WSnyder]

My set-tru front bolts are snug and I never touch them. I adjust and nothing moves after the fact.

 

[Walt Krafft]

My set-tru front bolts are snug and I never touch them. I adjust and nothing moves after the fact.

I tried that and did find movement, not much but some, so I started to tighten them.

 

[LVLAaron]

Same. It's pretty fiddly to use the small set screws... and make sure nothing moves... and then tighten the main bolts without it moving a tenth...

 

[jackieschmidt]

I leave my mounting bolts tight on my Set True. The four set screws move It just fine.

As for movement, it is always good machine shop practice to do all of your heavy cutting and then dial in the part for the final truing Before the finish sizes are established.

 

[Henryrifle]

I need to stop checking in on this Gun Project Questions and Gunsmithing forum. This topic is interesting enough to make me try a spider instead of a 4-jaw. Grizzly sells one that is perfect for my lathe.

A few posts above, @tobnpr talks about working opposing sides at the same time. Isn't that what we all have to do with a 4-jaw? After the first round of getting the barrel loaded in the chuck and reasonably centered using a live center, I usually loosen the jaw that is to high and tighten the jaw that needs to push the barrel down. I can't do that at the same time as there is no space on my setup.

I feel like I might be missing out on a more sophisticated technique that I don't understand. Maybe that is something you can do with a spider?

Thank you all for helping me to spend more money!

Henryrifle