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Gator/Fuerda EA Series 6-Jaw adjustable chucks
- Thread starter GaryK
- Start date
- Joined
- Nov 26, 2011
- Messages
- 99
Looks nice! Having no experience with 6-jaw chucks I'm curious, how small an object can be gripped by the six jaws? Will they close down to 1/8"? 1/16"?
Thanks,
Harry
Thanks,
Harry
- Joined
- Dec 13, 2012
- Messages
- 466
With this chuck it's about 3/8".
Anything that small or smaller I would be using a collet anyway.
- Joined
- Nov 26, 2011
- Messages
- 99
Thanks Gary. That's helpful information.
- Joined
- Oct 17, 2012
- Messages
- 126
Hey guys,
I've got a Rohm 4 jaw which was lotsa $, which I bought due to inability of the bundled 4 jaw to repeat. It has several issues; but the most significant is inability of the jaws to contact workpiece uniformly. Manf says that's normal. I don't know what "normal" is.
Further, the D1-4 taper ( no backplate) does not fit my spindle. I have to give it a rap laterally to seat, moves 0.003".
My biggest concern is regarding the jaw contact. By the by, all jaws are same. It's as if they are tapered inward toward the front. Very noticeable with alum, and apparent with SS or carbon steel.
What do you think?
Mike, Remlap Al
ps not meant to snipe your thread. And what is meant by " semi steel" ?
I've got a Rohm 4 jaw which was lotsa $, which I bought due to inability of the bundled 4 jaw to repeat. It has several issues; but the most significant is inability of the jaws to contact workpiece uniformly. Manf says that's normal. I don't know what "normal" is.
Further, the D1-4 taper ( no backplate) does not fit my spindle. I have to give it a rap laterally to seat, moves 0.003".
My biggest concern is regarding the jaw contact. By the by, all jaws are same. It's as if they are tapered inward toward the front. Very noticeable with alum, and apparent with SS or carbon steel.
What do you think?
Mike, Remlap Al
ps not meant to snipe your thread. And what is meant by " semi steel" ?
Last edited:
- Joined
- Nov 27, 2012
- Messages
- 7,854
That's one of the disadvantages of the 6-jaws, because of the extra jaws they can't grip smaller diameters. But for common fractional sizes I just use a DA collet, or switch to the 3-jaw if really needed.
The smallest diameter my Bison 6.25" 6-jaw is listed to clamp is 0.315", for the 5" 6-jaw it's 0.236". I make brass battery contacts out of 3/16" rod, here's my 5" Bison using a collet.
Generally for the higher quality chucks there are steel & semi steel chucks. Semi steel chucks have a cast iron body & the steel chucks have a forged steel body. Not sure about the pros & cons of either but cast iron body chucks have a lower max rpm rating. 6-jaw & 4-jaw chucks have a lower max rpm rating than 3-jaw chucks & smaller diameter chucks have a higher max rpm rating than larger diameter chucks.
My Bison 6.25" 6-jaw Set-Tru chuck has a max rpm rating of 2500 rpms which has a forged steel body. The Set-Tru adapter is also steel & is fully machined (& blanchard ground) which means no additional machining/skimming is required. Bison does not make 6-jaw chucks (solid or two piece jaws) in semi steel so can't compare there. But a Bison 6.25" 3-jaw (plain back) in steel has a max rpm of 4500 & the Bison 6.25" 3-jaw in semi-steel has a max rpm of 3000.
That's what's great about Fuerda, they offer the 6-jaw adjustable (TIR) chuck with two piece reversable jaws in both steel & semi steel. I wish they were around earlier. I don't think there are many manual lathes out there that are sized for a 6-8" chuck that can reach spindle speeds of 3000-4000 rpms.
Last edited:
- Joined
- Dec 13, 2012
- Messages
- 466
As far as not being able to grip a small diameter have you tried to remove every other jaw yet? That would in effect turn in into a 3J chuck.
Gary
- Joined
- Nov 27, 2012
- Messages
- 7,854
No but I have thought of that & I'm sure it would work. It's just so much quicker for me to use a collet & the run out is still more than acceptable. Also with the collet it allows me to still machine very short pieces that would hard to get tru in the jaws if the dia were large enough to fit. I just insert the piece then use another piece of the same diameter & push it forward from the back of the collet. I got the DA collets on ebay for cheap.