# Shopping for a Bigger Chuck



## erikmannie (Dec 15, 2020)

I have a 16” swing lathe & I am currently using a 10” D1-6 camlock 4 jaw with a 2 1/4” center hole. This is a Taiwanese chuck and the runout is about .0005” which I am very happy with. 

The problem is that my spindle through hole is 2.55” & I want to be able to take full advantage of that.

My main question: I wonder what the largest chuck is that I can put on a 5 HP, 16” swing lathe. I prefer 4 jaw independent chucks.

I don’t want mainland Chinese. A used chuck is okay, but it would have to be nice.

I can put on the 8” and 10” chucks that I have by myself. I am okay to buy a chuck that requires some sort of mechanical (e.g. hoist) assistance.

My machine goes up to 2000 RPM. I noticed that a lot of chucks have an RPM limit lower than that. I also see some D1-6 chucks with less than 6 mounting pins; I’m sure that’s fine, but I will buy one that has 6 pins.

Right now I have zero money, so I will be saving up.

I notice that a lot of chucks are much thicker (and thus heavier) than others. The 4J independent that I am using now seems to have the D1-6 pins on the chuck body (i.e. no backing plate). I don’t understand why some have a backing plate and some don’t.


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## erikmannie (Dec 16, 2020)

This is the only one that I have found so far that can be turned at 2000 RPM:









						TMX 10" 4 Jaw Independent Manual Chuck D1-6 Mount 3-857-1036P
					

TMX 10" 4 Jaw Independent Manual Chuck D1-6 Mount 3-857-1036P




					www.smalltools.com
				




The Bison-Bial model that looks a lot like this has a max RPM of 1500.

I think I saw a pattern of larger diameter chucks having a lower max RPM, but I am not sure of this.


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## Jubil (Dec 16, 2020)

Sorry I can’t answer your “main question” but for rpm question, I think there are a couple reasons for lower rpm on larger chucks. 
1. SFM. I don’t know what material you are turning but surface feet per min. would be rather high. SFM = .262 x dia. x rpm. In your case .262 x 2.55 (spindle id)x 2000 =  1336 sfm. Most of the stuff I cut at 50-250 sfm. I seldom turn my lathe 900 rpm. I am not doing production work, so I’m in no hurry. Besides I get nervous with things spinning that fast in my face.
2. Centrifugal force. The material the chuck is made of has a bearing on the integrity of the chuck. 
I hope this is not offensive, I am just trying to explain the little that I know. 
Surely others here can explain better than I. And correct me if I’m wrong.

Chuck


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## NC Rick (Dec 16, 2020)

My 15" lathe has a 12" 4 jaw.  I'm not willing to run it over 1000 rpm.  It has a lot of mass and inertia and I think it is possible to have the jaws loose holding force at higher rpm.  I don't like using a big Chuck if I'm not doing big work.  My 50 year old 10" south bend, 3 jaw won't clear the cross slide and is pretty worn so I replaced it with an 8" from Shars.  I'm pretty happy with it and it is very versatile.  I am keeping the 10 inch for when I need the size (near 3" through).


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## mksj (Dec 16, 2020)

You would not be spinning a 10" or 12" chuck at 2000 RPM, with a 2.5" stock it works out to a SFM of 1300. A realistic maximum speed would be in the 1500 RPM range, and most people would probably stay under 1000 RPM with a 10-12" chuck. As far as size, depends on the orientation of the jaws but you need to keep a minimum of at least 4 jaw teeth engaged, and maybe more for a large chuck at speed. You could probably fit a 12" chuck on a 16" swing lathe, but more for low speed big diameter work with the jaws reversed. if you are swinging larger diameter stock you have material imbalance and use much lower RPM's. The maximum diameter work holding with the jaws reversed is approximately equal to the diameter of the chuck. Chucks that are made from semi-steel (cast iron) having a lower maximum speed then the same chuck in forged steel, many chuck manufactures offer both.

All these chucks have a bore diameter over 2.5", the first one by TMX is rated to 2000 RPM, Bison also has the equivalent. Assuming you do not need the 2000 RPM speed range you can use the semi-steel, in a 10" the maximum chuck rated speed is usually in the 1500 RPM range. Assuming you will only be using this occasionally then it does not pay to get anything expensive. If it was a gunsmith and it was their primary chuck, the the 10" 4J independent TMX or Bison with 2 piece jaws might be a better option. I just went through this selection with another individual with a 14" lathe D1-5  and he purchased the Bison forged steel in a 10" version of the TMX. The two piece jaws would allow the use of soft jaws.









						TMX 10" 4 Jaw Independent Manual Chuck D1-6 Mount 3-857-1036P
					

TMX 10" 4 Jaw Independent Manual Chuck D1-6 Mount 3-857-1036P




					www.smalltools.com
				











						Bison 10" 4 Jaw Independent Manual Chuck D1-6 Mount 7-857-1036F
					

Bison 10" 4 Jaw Independent Manual Chuck D1-6 Mount 7-857-1036F




					www.smalltools.com
				












						10" 3-JAW SELF-CENTERING LATHE CHUCK D1-6 MOUNTING--0.003" TIR--new  | eBay
					

Find many great new & used options and get the best deals for 10" 3-JAW SELF-CENTERING LATHE CHUCK D1-6 MOUNTING--0.003" TIR--new at the best online prices at eBay! Free shipping for many products!



					www.ebay.com
				











						10" 4-JAW SELF-CENTERING CHUCK top & bottom reversible jaws w. D1-6, D6 adapter  | eBay
					

Find many great new & used options and get the best deals for 10" 4-JAW SELF-CENTERING CHUCK top & bottom reversible jaws w. D1-6, D6 adapter at the best online prices at eBay! Free shipping for many products!



					www.ebay.com
				











						10" 4-Jaw D1-6 Cam-Lock Lathe Chucks Manual Independent Jaws  | eBay
					

10" 4-Jaw D1-6 Cam-Lock Lathe Chucks. Jaws are individually adjustable, allowing firm gripping of odd shaped work. Hardened and precision ground reversible jaws. Direct Mounting chuck with Camlock Nose.



					www.ebay.com
				











						10" D1-6 4 Jaw Chuck at Grizzly.com
					

We are proud to offer Bison Lathe chucks. This well respected brand of chucks has been the long accepted standard for high quality European work holding technology.<P>These direct mount 4-jaw chucks are made with semi-steel bodies, hardened and ground jaws and have independently adjustable...




					www.grizzly.com
				











						10" 4-Jaw Independent Chuck D1-6 at Grizzly.com
					

This direct mount 4-jaw chuck features jaws that move independently. Each chuck comes with studs in the back and hardened reversible jaws. The body is made of semi-steel. D1-6 is a type of spindle found on certain metal lathes. It is a cam-lock style mount that requires the chucks to have...




					www.grizzly.com


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## erikmannie (Dec 16, 2020)

All of these responses are very helpful. I will have to save up for a long time, so I will have a lot of time to think about it.

I already have the 10” Taiwanese chuck with a 2 1/4” diameter center hole, so it might be financially wasteful and even redundant for me to buy a 10” chuck with a 2 1/2” diameter center hole.

If I had to guess, I would imagine that I will end up buying a used, quality 12” 4J independent with a center hole larger than 2 1/2” and obviously adhering to the max RPM.


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## NC Rick (Dec 17, 2020)

I worry about my stupid mistakes, like accidentally switching the one lever into high instead of low and suddenly finding the 12" Chuck running 2000 rpm.  I have done it, it's difficult to not make a mistake now and again.. that could have been a disaster holding the 10" diameter cast iron adapter plat i made a few weeks ago as I was clamped on just less than a 1/4" of the edge.  Yikes!


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## Jim F (Dec 17, 2020)

Really need to to think about the mass and speed.....
I do not want to be near a 16" chuck at 2K
My 5" at 1K is kinda touchy....


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## Shootymacshootface (Dec 17, 2020)

CME is my go to for chucks and back plates.
These guys.


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## erikmannie (Dec 20, 2020)

So I have been researching this extensively. Long story short, I am going to save up for the Toolmex 12”, 4 jaw independent D1-6 chuck below. It will take me about a year to save up.









						TMX 12" 4 Jaw Independent Manual Chuck D1-6 Mount 3-857-1236P
					

TMX 12" 4 Jaw Independent Manual Chuck D1-6 Mount 3-857-1236P




					www.smalltools.com
				




There is a Jet 12” 4J chuck (made in Taiwan) that I was looking at, but there is no information online about the diameter of the center hole.

The Bison chucks spec out, but there is one thread on the less friendly machining forum that says there may be an issue with the Bison jaws gripping tightly. 

I spoke with Ashley, a rep for Toolmex. She says that TMX used to be the distributor for Bison, but the 2 companies parted ways. She said that the TMX and Bison chucks are made in completely different factories (but both are made in Poland).

One main difference between the TMX chuck and the Bison chuck is that the TMX body is forged steel whereas the Bison is cast iron. Also, the TMX has two piece jaws, whereas the Bison has one piece jaws. I would like it if I could just bolt on soft jaws.

The max RPM on the TMX is the highest of all the chucks that I looked at.

One more thing on Polish made chucks. Apparently the Gator chucks are made by Polish guys who used to work for Bison and now they are producing what they say are high quality chucks in mainland China.


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## erikmannie (Dec 20, 2020)

Toolmex put me in touch with a TMX distributor in my city, and the local distributor quoted me a price that was a whopping $640 higher for the exact same chuck listed on SmallTools.com.


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## mksj (Dec 20, 2020)

They both offer semi-steel and forged bodies, the Bison forged steel is the 7-857-1236F. They are all patterned off of the Bison, including the Gator. The Gator is made in China, and there have been more QC issues with fit and finish, overpriced for what you get. But then Buck, and a lot of other notable chuck makers have shifted production to China. I recall one post where they compared a Buck chuck to a Chinese mainland one, identical in every way other than the branding and the Buck was 2X the cost. It varies. As far as holding power, on these larger chucks the jaws are much wider and courser, they are made for large stock not small. I recently had heard that Bison may be stopping production on the forged steel versions on this 2 piece 4J  line of chucks, according to a US distributor they were rarely selling this model in a forged body. Makes sense, no reason to spin a chuck this size past 1000 RPM.








						Bison 12" 4 Jaw Independent Manual Chuck D1-6 Mount 7-857-1236F
					

Bison 12" 4 Jaw Independent Manual Chuck D1-6 Mount 7-857-1236F




					www.smalltools.com
				





As far as fit and finish/QC from the ones I have and having spoken to others: Bison>TMX>>Gator in descending order. Typical price difference from the Bison, TMX is about 10% less and Gator about 25% less.


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## erikmannie (Dec 20, 2020)

mksj said:


> They both offer semi-steel and forged bodies with 2 piece jaws, the Bison forged steel is the 7-857-1236F. They are all patterned off of the Bison, including the Gator. The Gator is made in China, and there have been more QC issues with fit and finish, overpriced for what you get. But then Buck, and a lot of other notable chuck makers have shifted production to China. I recall one post where they compared a Buck chuck to a Chinese mainland one, identical in every way other than the branding and the Buck was 2X the cost. It varies. As far as holding power, on these larger chucks the jaws are much wider and courser, they are made for large stock not small. I recently had heard that Bison may be stopping production on the forged steel versions on this 2 piece 4J  line of chucks, according to a US distributor they were rarely selling this model in a forged body. Makes sense, no reason to spin a chuck this size past 1000 RPM.
> 
> 
> 
> ...



That is super helpful. Ashley the TMX rep was pretty convincing that TMX was better than Bison. Now that I see that Bison offers a forged steel body & 2 piece jaws, I will reconsider Bison. Anybody should be happy with a Bison. The one thread (about poor jaw grip) on Practical Machinist may be an aberration.

Regarding RPM & holding small stock, there is a good chance that I will leave the 12” 4J in the lathe most of the time. I am not a fan of 3J chucks, the center hole in my current 4J restricts my pass through diameter, & I am right at the point where my back is going to become injured. 

I have a 10X30 lathe that goes up to 2000 RPM that I can use for stock that is too small to put in a 12” chuck.

I forgot to mention that TMX chucks have interchangeable jaws with 2 other brands; I don’t remember the name of the brands, but one is Japanese (probably Kitagawa), and Bison is not one of the brands. This doesn’t really matter to me because I would just buy a set of soft jaws when I purchased the new 12” chuck.


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## erikmannie (Dec 20, 2020)

This is still a contender:









						Pratt Burnerd 12" 4 Jaw Independent Manual Chuck D1-6 Mount 1214423
					

Pratt Burnerd 12" 4 Jaw Independent Manual Chuck D1-6 Mount 1214423




					www.smalltools.com


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