Looking For a Small 4 Jaw Chuck With 5C Mount

I have to make a number of different profile small parts for a prototype project. Some will have an OD of .187" or less. I was thinking of purchasing a 4 jaw independent lathe chuck in the 3" or 4" diameter with a 5C mount to hold the parts. I've seen dozens of them ranging in price from under $50.00 to well over $200.00. Some have a reasonable written description, but I have no experience with chucks of this size, and would like to avoid buying a piece of junk.

I'm looking for something of relatively good quality that won't cost a fortune since this may be the only job it ever gets. So far all those I've investigated have a minimum outside jaw grip range in the .200" range. I did see a couple that went down to .160" but they were of questionable quality. Is anyone aware of a reasonable quality chuck that will accomplish what I'm trying to do?

Just curious, have you considered a collet chuck?

crossthread said:

Just curious, have you considered a collet chuck?

Click to expand...

I do have a full set of 5C collets and chucks for both my lathes. Several of the parts needing to be turned will need to be offset from center to create cams. That's why I'm interested in the possibility of finding and using an independent 4 jaw chuck. I suppose I could create a fixture fo the parts and use a chuck with a larger grip range. I'm just trying to simplify the operations.

Offset......5C emergency collet...Bore the gripping hole at the needed offset ....
Cheers Ross

I have both a 3 jaw scroll chuck and a 4 jaw independent with changeable jaws with a 5C back plate. They are super useful. I use them on a cheap spin indexer to mill features on my BP clone. I picked them up during a trade fair in Shanghai in 2005. They are much faster to set up for one off jobs than my 8" super spacer. I also have another chuck set with R8 back plates. They work well holding bi-metal hole saws.

I made a 3 jaw version of what you want by turning a 5C fixture mount to fit the back of a 5" Hardinge chuck.

Tom

Off set parts

projectnut said:

I have to make a number of different profile small parts for a prototype project. Some will have an OD of .187" or less. I was thinking of purchasing a 4 jaw independent lathe chuck in the 3" or 4" diameter with a 5C mount to hold the parts. I've seen dozens of them ranging in price from under $50.00 to well over $200.00. Some have a reasonable written description, but I have no experience with chucks of this size, and would like to avoid buying a piece of junk.

I'm looking for something of relatively good quality that won't cost a fortune since this may be the only job it ever gets. So far all those I've investigated have a minimum outside jaw grip range in the .200" range. I did see a couple that went down to .160" but they were of questionable quality. Is anyone aware of a reasonable quality chuck that will accomplish what I'm trying to do?

Click to expand...

I used to turn offset cams. Like the ones used in KDK qctp. I used 5c emergency collets. I put collets in a fixture on mill. Dialed the offset and bored them. You can buy emergency collets at Shars tools for $7.50 ea. Then you can save the offset collet or bore them bigger for another job.

Jim Sehr


Jim Sehr

projectnut said:

I was thinking of purchasing a 4 jaw independent lathe chuck in the 3" or 4" diameter with a 5C mount to hold the parts.

Click to expand...

These are available from MSC. Very handy.

Hi projectnut:
Sherline sells these:

Quick-Change 5C Chucks

And these:

5C 3.1″ 4-Jaw Independent Chuck – Sherline Products

The second one is smaller and will grip a smaller part.

They are well made and will do what you want.
Smallest part the little one will grip is 2mm square.

Cheers

Marcus
Implant Mechanix • Design & Innovation > HOME
Vancouver Wire EDM -- Wire EDM Machining

AlfaGTA said:

Offset......5C emergency collet...Bore the gripping hole at the needed offset ....
Cheers Ross

Click to expand...

On long running jobs I have sent a hard collet out for wire EDMing the offset bore. When running bar stock on a long running job we screwed in a bushing in the back of the collet and had the assembly wire EDMed to better support the bar when running higher RPMs.


Not a 5C collet, but the idea is there. Reamed the bushing slightly over bar size and heavily chamfered to ease starting the bar. Collet was originally 1/4 inch now 1/2 inch and .067 offset.

implmex said:

Hi projectnut:
Sherline sells these:

Quick-Change 5C Chucks

And these:

5C 3.1″ 4-Jaw Independent Chuck – Sherline Products

The second one is smaller and will grip a smaller part.

They are well made and will do what you want.
Smallest part the little one will grip is 2mm square.

Cheers

Marcus
Implant Mechanix • Design & Innovation > HOME
Vancouver Wire EDM -- Wire EDM Machining

Click to expand...

Thanks for the information. This is what I'm looking for. The specifications are the tightest I've seen as far as minimum grip dimensions for the jaws in both the inner and outer configurations.

I'm sure emergency collets could do the trick. However I can foresee the possibility of needing dozens of them if cam dimensions and offsets change slightly. I've made a number of cams with larger 4 jaw chucks. Dialing in the offset is quick and simple compared to having to bore, and potentially rebore a collet for the same purpose.

Thanks everyone for your input and suggestions.

I put this together 20yrs ago for use on a cutter grinder, it is an important tool for me.

The chuck is a vintage Union 4" 4 jaw, it is precision, not junk import. Chucks like this are worth the price!
The shank was purchased from MSC, it could be an import, cant remember.
This is a nice unit for what I use it for.


and,



That is an 8" Union in the background. Both chucks were found on ebay...

The import chuck with 5c shank linked to above above is a piece of crap, as can be seen the jaw adjusting screws are threaded to the chuck body! Junk! The 4" Union chuck, is built like the 8" Union chuck. Skinner made great small chucks also.

good luck.

donie said:

I put this together 20yrs ago for use on a cutter grinder, it is an important tool for me.

The chuck is a vintage Union 4" 4 jaw, it is precision, not junk import. Chucks like this are worth the price!
The shank was purchased from MSC, it could be an import, cant remember.
This is a nice unit for what I use it for.


That is an 8" Union in the background. Both chucks were found on ebay...

The import chuck with 5c shank linked to above above is a piece of crap, as can be seen the jaw adjusting screws are threaded to the chuck body! Junk! The 4" Union chuck, is built like the 8" Union chuck. Skinner made great small chucks also.

good luck.

Click to expand...

I have nearly a dozen independent 4 jaw chucks in the shop for different machines. They range in size from 5" to 12". Most are American made brands like Union, Cushman LW, and Skinner. I also have a couple imports from Poland. They ALL have the adjusting screws threaded into the body. My current ones all appear to be acme threads.

Those in the Sherline pictures don't appear to be acme, and I doubt they are as strong, however we're talking about clamping a part less than .187" in diameter. They may not be the strongest, or the best quality in the world, but I haven't found anything domestic or imported so far that comes closer to what I'm looking for.

You need to look at Levin items, that is the next step in that direction. And really the smaller it gets the easier it gets, if you have the right equipment.
Good luck to you

donie said:

You need to look at Levin items, that is the next step in that direction. And really the smaller it gets the easier it gets, if you have the right equipment.
Good luck to you

Click to expand...

Levin stuff if awesome, but for chucks they sourced them from JF, now Maprox. I have a bunch, definitely not "budget" items, but worth the price.

Maprox

Hi again projectnut:
Yes Levin is awesome but it goes for Levin prices and it won't clamp your parts any better than the Sherline one will.

I have a Sherline 4 jaw I bought in 1997 and it's still working like a champ.
I turn with it, I cylindrical grind with it, I do all kinds of wild and wonderful things with it and it has been more than adequate for everything I've ever done.
I can still center a part accurately with it, even after twenty years of using it for necking down carbide cutters and other horrid shit that will play havoc with chucks.

I have ZERO complaints with it and it's under 200 bucks, brand new out of the box.

Cheers

Marcus
Implant Mechanix • Design & Innovation > HOME
Vancouver Wire EDM -- Wire EDM Machining

I’ve found the main reason a large chuck won’t grip small diameters is due to the width of the gripping area.
If you can remachine the 45 degree on all 4 jaws to a near knife edge thickness at gripping surface a large chuck can hold whatever that thickness is plus some for give. Most wouldn’t dream of doing that to one of their chucks but it might be worth looking into?

Danny VanVoorn said:

I’ve found the main reason a large chuck won’t grip small diameters is due to the width of the gripping area.
If you can remachine the 45 degree on all 4 jaws to a near knife edge thickness at gripping surface a large chuck can hold whatever that thickness is plus some for give. Most wouldn’t dream of doing that to one of their chucks but it might be worth looking into?

Click to expand...

One can also set dowel-pins or Copper, Bronze or Brass goods into a jaw, located and shaped as required.

Otherwise, easier to select than modify, if one but considers it in advance off the back of having had the need many times before.

Ex: Just in 4-J goods bought NEW/NOS, not used, in 6" to 8" "nominal" (inch and metric), I have:

- thick, wide, 4-J Yuasa with heavy body and large actuating screws according

- very thin jaw Bison

- medium thin jaw SCA

- medium thick(er) jaw Feurda/Gator & San Ou

Plus a few odds and sods Cushman Etc bought used, also with variations in jaws.

D1 or similar mounts. Reasonably rapid swap.

The diversity was not an accident. Pay attention to major-maker FULL line.

What you want might be positioned to be sold as indexer / Dividing Head, or grinder goods, have those thinner jaws, but not be meant for "general purpose" heavier gripping on lathes.

That said, I'd modify a brand-new San Ou in a New York Minute if the need arose.

They are not half bad for small money, 4-J centering "goodness" being up to you, not at the mercy of the OEM quality or wear/damage condition of a scroll.

San Ou have several small 4-J, both flat-back and 5C, both independent and "self (off) centering", at very attractive prices.

When on promotional pricing - sometimes under US$ 50, net, brand-new, they can be cheap enough to put by an extra - or two - specifically FOR possibly modifying or task-specific fixturing, the benefit paying-off in only one or few uses.

No cause for complaint, "so far", either. No free magic. Just basic white-bread serviceable.

Decent 3-J, OTOH, one could do worse than go to the Czechs - ToS Svitavy - for good value for money.

2CW

"Decent 3-J, OTOH, one could do worse than go to the Czechs - ToS Svitavy - for good value for money."

You are a "troll" with a Rotted Mind termite, you simply have never displayed any machine work.
As, your other peer had said, you need to do some work, display photos for some "street credibility" of that you have none. Get with the program termite, actually do something...

donie said:

"Decent 3-J, OTOH, one could do worse than go to the Czechs - ToS Svitavy - for good value for money."

You are a "troll" with a Rotted Mind termite, you simply have never displayed any machine work.
As, your other peer had said, you need to do some work, display photos for some "street credibility" of that you have none. Get with the program termite, actually do something...

Click to expand...

Well here you are, "stalking" into yet-another random thread - whining in need for your "fix" of criticism, oh mendacious masochist!

"Machine work" was 55-plus years back, fool. You may live in your rear-view-mirror. I do not NEED to do.

I AM "doing something"!

With more-recent skills...

Assisting a mendacious FRAUD with "wound collector" mental disorder to PROVE exactly what he IS .... in front of God, PM, Google, and the whole of the internet.

Not that you have been all that lazy about helping yerself to that branding.

Seems choosing the most public available of venues for self-flagellation is the only skill you have ever bothered to work HARD at, oh needy-greedy drama-queen?

Downside? It never WAS the fault of "other", was it?

You finally grew too damned greedy for ALL the glory in it to even share the blame!

What a shiddy-piddy!

Keep on digging your "monument"!!! Oh.. might pray it don't rain all that much?

Not "too soon", anyway.

Inefficient use of resources you should accidentally drown yourself in your own self-pity-shitty while you still have the energy left to create more OF it?

Patience. Take a nap now and then. Dig your hole slowly. There's time, yet.

Glenn Jones - We've Only Just Begun (1987 Apollo)(lyrics in description) - YouTube