RANT: 5C Collets Chuck, D1-4 Cam-Lock

[JimDawson]

I need a 5C collet chuck for an upcoming project so of course I went to Ebay to find something cheap. OK, I know that I’m not going to get Hardinge quality, but I expected that the specifications would be reasonably close to the real world. It’s my fault I guess, $260 was pretty cheap. I’m glad that I didn’t spend more thinking that I would get higher quality in Chinese tooling. It’s pretty much a crapshoot.






The TIR was advertised as 0.0004, I could live with even +/- 0.0004, but 0.004 TIR is a bit too much.

Please understand that the problem here is that the chuck does not match the advertised specification. If it was not advertised as 0.0004 TIR, I would not be writing this.

Just to be sure, I checked my lathe spindle; the TIR is <0.0001. About 20 years ago, when I first bought the lathe it was 0.0003 TIR, so I re-ground the spindle to get it to zero.


The internal nose taper seems to be concentric with all of the surfaces on the OD. This means that the mounting surface is not machined concentric with the rest of the chuck. Rather than putting the chuck on a D1-4 spindle to do the final grinding, they apparently chucked on the OD. Due to the design of the chuck, there is no way to adjust the concentricity. I’ll re-grind the taper and get it right.


The other issue is the bevel gears in the chuck. Everything is so sloppy that the gears jamb when loosening, it seemed to work OK when tightening. I went in and deburred and cleaned up the internal parts and got it to work pretty well.


The outside finish is good with the exception of the normal lack of deburing.


I am not going to contact the seller (an importer) to complain, I’ll just fix it and go on with life.


The Chinese lack of quality control is amazing. If we ever get into a war with China I can only hope that their weapons have the same fine quality.


End of rant.

 

[Don B]

Don't blame you for the rant, it's very frustrating when a tool clearly doesn't fall within the manufactures claimed tolerances/maximum run out, I purchased what was advertised as a super precision milling vise once, it rocked .025 from corner to corner, when I complained I was told some people are just to fussy an can never be kept happy....? I'm not sure anyone would be happy remachining what was advertised and sold as a "Super Precision Milling Vise":nuts:

 

[Ray C]

Jim, this is precisely why I want nothing to do with integral-back chucks. If they're not dead-on, they're dead-off -with virtually no chance of fixing it. I'm scratching my head about that style... It's a rotten egg.

All my manual lathe chucks are (and will be for the foreseeable future) two-piece. That way, I can customize the interface between the spindle and backplate and then, the interface between the backplate and chuck. And furthermore, I ever get a lathe with a different mount type, my chucks are preserved and all that's needed are backplates and a couple hours of my time.

I tell all my clients to go this way -at the expense of spending 1-3 hours on the phone giving instructions on how to true things up but at least, I don't spend 1-3 hours on the phone getting chewed-out for steering them in the wrong direction.

... Sorry to hear you got a lemon but I'm glad you posted so I can beat my drum about this ridiculous design.


Ray

 

[zmotorsports]

I agree with Ray, I like having the backing plate separate vs. integral for the ability to address this very issue.

I just picked up a 6" 6-jaw chuck and the guy had both styles, integrated D1-4 or the divorced style. I opted for the separate backing plate/chuck style vs. being completely disappointed down the road when I install it and find out the runout is beyond expectations, which I hope it isn't.

Mike.

 

[Ulma Doctor]

thanks for the post Jim,
i had contemplating doing the same thing, although i don't have a D1 spindle.
i have a 2 3/8" x 8 tpi spindle and have a similar problem, i would like to use 5C collets for accuracy.

i'm wondering if a MT5 to 5c spindle adapter from grizzly would be a better step in the right direction?

 

[dave2176]

thanks for the post Jim,
i had contemplating doing the same thing, although i don't have a D1 spindle.
i have a 2 3/8" x 8 tpi spindle and have a similar problem, i would like to use 5C collets for accuracy.

i'm wondering if a MT5 to 5c spindle adapter from grizzly would be a better step in the right direction?

If the MT5 was in an accurate holder like a large spindle it would be accurate.Could you make your own adapter?


Dave

 

[JimDawson]

If the MT5 was in an accurate holder like a large spindle it would be accurate.Could you make your own adapter?


Dave

You could make a MT5 to 5C adapter and it should be just fine, I just don't have the time to spend on it. You would also have to make a draw bar to pull the collet in. There are a lot of handwheel type 5C collet closers available. That is the way I guess I should have gone, or as Ray C suggested, gotten a plane back chuck and a backplate for it.

 

[Ray C]

You could make a MT5 to 5C adapter and it should be just fine, I just don't have the time to spend on it. You would also have to make a draw bar to pull the collet in. There are a lot of handwheel type 5C collet closers available. That is the way I guess I should have gone, or as Ray C suggested, gotten a plane back chuck and a backplate for it.

If that chuck were mine -and assuming I took pity on it, I'd remove the lugs, get a backplate -and make a decent chuck out of it.

Ray

 

[Walsheng]

I just bought a G4003G and got the Bison 5-C chuck for it. The chuck wasn't very cheap, around $560, so I was hoping for the best. I put it on, put the Interapid thenth indicator on it and the needle didn't move! I had to do it a couple of times to make sure the indicator was actually touching, not that I ever made that mistake before, and it did not move. Took it off, put it back on just to make sure and same results.
Not only that but the fit, finish and movement was impressive.
I am thinking of getting a larger 3 jaw chuck for the lathe and I will have to consider a Bison.

John

 

[tripletap3]

There was a post here last year or so where someone bought on of the inexpensive 5C direct mount chucks from Ebay and they had the same issues and if I recall right it turned out to be a nightmare. After doing some research for myself it seems that there must be a factory making a particular 5C chuck that is real crummy. There are other clones in the $350 range that will get you in the .001 range and of course the $550+ Bison that will do what you expect. This is a classic example of what we see everyday of numerous China factories making the same looking clones with wide degrees of quality.