Hydraulic 3-jaw vs 5C collet chuck

I'm looking to convert my manual chuck over to a power chuck on my CNC lathe. Hydraulic 3-jaw with all the required bits seems a little more than I want to spend right now, so I'm thinking about a pneumatic 5C chuck. Main question is, what am I giving up?

My production parts would either fit into 5C collets (under 1" bars), or are larger discs that I'm planning to use step collets on.

This is the chuck I'm considering at about $2600:
5C, Dead Length, Pull Back, Collet Power Chucks
Self-contained and I could switch back to a manual chuck if I ever need for some random prototyping part, but most other parts I'm considering are smaller and would easily fit into standard 5C collets.

droshi said:

I'm looking to convert my manual chuck over to a power chuck on my CNC lathe. Hydraulic 3-jaw with all the required bits seems a little more than I want to spend right now, so I'm thinking about a pneumatic 5C chuck. Main question is, what am I giving up?

My production parts would either fit into 5C collets (under 1" bars), or are larger discs that I'm planning to use step collets on.

This is the chuck I'm considering at about $2600:
5C, Dead Length, Pull Back, Collet Power Chucks
Self-contained and I could switch back to a manual chuck if I ever need for some random prototyping part, but most other parts I'm considering are smaller and would easily fit into standard 5C collets.

Click to expand...

You'd be GAINING the PB's "dead length" feature.

Might want to look at 2J, 3J as well as 5C. EG: Dunham, Rovi.. others. CAVEAT: Not all are "through" for bar work. Some are pre-cuts or second-op only though.

Collet Chucks - 5c, 16C, 3J,  And Quick Change

As to the power 3-J? Check out power TWO jaw when you get back around to that "opportunity".

Gots to "tool" the top-jaws, but there's a LOT that can cover, some of it downright weirdly shaped.

thermite said:

You'd be GAINING the PB's "dead length" feature.

Might want to look at 2J, 3J as well as 5C. EG: Dunham, Rovi.. others. CAVEAT: Not all are "through" for bar work. Some are pre-cuts or second-op only though.

Collet Chucks - 5c, 16C, 3J,* And Quick Change

As to the power 3-J? Check out power TWO jaw when you get back around to that "opportunity".

Gots to "tool" the top-jaws, but there's a LOT that can cover, some of it downright weirdly shaped.

Click to expand...

PB does make a 3-jaw pneumatic chuck as well, only issue there is that for my spindle it would be a special order, it's also more than double the cost of the 5C.

I'm really looking to do just 1" or under bar work, otherwise pre-cut and 2nd op slugs on the larger stuff. My spindle bore is only 1.3" anyway so it's not like I can ever do the 3.25" bars I'd need, never mind the difficulty parting that off in 304 stainless.

droshi said:

PB does make a 3-jaw pneumatic chuck as well, only issue there is that for my spindle it would be a special order, it's also more than double the cost of the 5C.

I'm really looking to do just 1" or under bar work, otherwise pre-cut and 2nd op slugs on the larger stuff. My spindle bore is only 1.3" anyway so it's not like I can ever do the 3.25" bars I'd need, never mind the difficulty parting that off in 304 stainless.

Click to expand...

So long as spring collets will do yah for all the high-volume stuff, I don't much see the need for POWERED chucks anyway.

2J won't make your bore any larger. They do grip better and last longer than 5C, same service. 4-way split vs 3-way split as well as being stouter.

Also cost twice as much per collet as 5C.

But that's offset by longer life and better service, during, so.. worth a test with a used manual closer, Sjogrens being cheap and common, used.

I have both, of course. Also Burnerd Multisize.. then the sloooooow tribes.. Rubberflex 9XX, ER 40, ER 20, TG-100, MANUAL 2-J, 4-J, 6-J. No 3-J in-use nor planned.

Can't beat 5C for FAST, cheap and ubiquitous, more than just "round" and OD-clamped, but 2J can be easily as fast and perhaps cover more than a few of those larger slugs, too.

Power vs manual - though a manual collet closer chuck would probably be fine if it was the lever style for a while, in the future I'm hoping to get a robot arm and automate my process even more. My parts aren't really high volume, so robot speed isn't important, but just being able to make them in small batches without so much part handling would be ideal. Unfortunately I can't do a bar puller for my parts, they are just too long or too large, so flipping bars and slugs is pretty much always needed.

Anyway, the power chuck is my first stop on the way to that goal ideally!

droshi said:

Power vs manual - though a manual collet closer chuck would probably be fine if it was the lever style for a while, in the future I'm hoping to get a robot arm and automate my process even more. My parts aren't really high volume, so robot speed isn't important, but just being able to make them in small batches without so much part handling would be ideal. Unfortunately I can't do a bar puller for my parts, they are just too long or too large, so flipping bars and slugs is pretty much always needed.

Anyway, the power chuck is my first stop on the way to that goal ideally!

Click to expand...

Some of those linked are half (or less) what you initially cited for the PB. I don't rate 600 Group as bad-actors, but neither do they walk on water vs at least two of the other brands.

Do your own due diligence at least until you have some experience as to whether it is worth it, your specific needs, is vs - my preference- a 2J or the multisize front "loop" closer. No drawbar needed as a rear-lever uses.

Power can, of course, be tied-into the machine's cycle, hopefully hold consistent clamping force, and doen't get tired.

I have PB's B60 self contained collet chuck.Air Powered, Front Mount, B6, Dead Length Collet Chucks went with it over a hydraulic three jaw simply because jaw chucks make big bangs when things get stuck in them - collet chucks dont
In general its a nice chuck, but be warned that it needs to be well lubricated (like dripping) or it seizes up. Even then, it will seize up a few times a year - the floating collar where the air lines attach has a very small gap to the main chuck body, and when (not if) something gets stuck in that gap, the floating ring joins the rest of the chuck in spinning at 2000 rpm - the airlines rip out and make a lot of noise, and you have to go home and change your pants
So - in between seizes, its a great chuck...

commachines said:

I have PB's B60 self contained collet chuck.Air Powered, Front Mount, B6, Dead Length Collet Chucks went with it over a hydraulic three jaw simply because jaw chucks make big bangs when things get stuck in them - collet chucks dont
In general its a nice chuck, but be warned that it needs to be well lubricated (like dripping) or it seizes up. Even then, it will seize up a few times a year - the floating collar where the air lines attach has a very small gap to the main chuck body, and when (not if) something gets stuck in that gap, the floating ring joins the rest of the chuck in spinning at 2000 rpm - the airlines rip out and make a lot of noise, and you have to go home and change your pants
So - in between seizes, its a great chuck...

Click to expand...

Bummer to hear, I did get the 5C chuck and it's getting delivered tomorrow. I checked with several others and a few said that seizing is usually due to a bad FRL, so I had hoped cranking up the lube on that would take care of things.

A couple other things that may help:
* The chuck supposedly only lubricates when you actuate air, so I guess if you leave something chucked for a very long time that may not be ideal
* At startup, putting air and then actuating a few times, then run at a low rpm to warm it up is a good idea

I'm still hoping it was a good buy, getting a pneumatic cylinder mounted at the back of my spindle was going to be a challenge, so this front-mount style was pretty much all I could go with easily.

Needing maintenance is one thing, but I wouldn't be able to accept that it will just seize up on me now and then, if it happens because I forgot to do something correctly, then I can learn to do better...if that's just how the chuck is, then I'll have to figure something else out.

I'll report back either way after I've had a chance to use it for a while.