Lathe chucks

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rockyrude

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My 12" craftsman lathe came with a 4" chuck, I want to upgrade to a 6" chuck. Does price equal quality? I am seeing chucks ranging from $75 - $200, I obviously want the best quality I can get.
 
My lathe came with a Chinese 6" 3 jaw that is OK. I don't think any 3 jaw chucks are good enough to turn the work around and be dead on. I did buy an 8" 3 jaw from Taiwan. It repeats much better but still not perfect. And it was a lot more expensive. For good work I still put the 8" 4 jaw on after first turning all I can in my 3 jaw chucks. Parts smaller than 1 1/8" diameter go in my 5C collet chuck. It centers really well.
 
You can pay even more- Pratt-Burnerd are very nice chucks and would set you back about 400$
-Mark
 
The real question is....How good is good enough for what YOU need it to do. It is not purely better costs more. Expensive does not always mean good, but good is never cheap. Yes even the cheapest junk made will occasionally get lucky and make one of something that is dead on. But do you want you accuracy to rely on luck? So if you want good expect o pay more for it, now you just need to decide how good do you really need. If everything you do is realistically +/- .005 in then you do not need or want equipment that can go to millionths of an inch, IF you could even afford it.

The most accurate you can get a 3 jaw is to get something adjustable like a Set True You then have the capability to dial it in to what ever accuracy you need for the job at hand.
 
Silly question: If you use a Set True 3 jaw, when you reverse the work in the chuck, what are the odds that at a different work diameter the position will be dead on? If it is not and you need to adjust the 4 screws on the Set True, is that much of an advantage over just swapping to a 4 jaw? Maybe the scroll in a Set True chuck is dead on uniform? I know that my semi-decent Chinese 6" chuck will have slightly different runouts depending on the work diameter. Seems inherent with a scroll.

On the other hand, A Set True collet chuck once dialed in, always seems to hold the work true when swapped end for end. The accuracy here would seem to be with the collets, not the chuck.
 
I have an original Atlas 3-jaw, which I believe came with the lathe when new. I use the 3-jaw chuck only for the first operation - such as turning stock to a diameter. If I have to remove and replace or re-orient the work then I go to a collet chuck of 4-jaw chuck. The way I use a 3-jaw it hardly mattes how good or bad it is. My advice is to spend your money on a good 4-jaw and/or collet system. If your work is not too large to fit, collets can be amazingly good.
 
Larry$ said:
Silly question: If you use a Set True 3 jaw, when you reverse the work in the chuck, what are the odds that at a different work diameter the position will be dead on?
Click to expand...
That depends on the chuck. I got a Pratt-Burnerd adjust-tru two or three years ago as my first set-tru type chuck, and machined a NOS PB back plate to fit. This chuck does a fantastic job of holding zero along the length of the scroll. I flip parts over and get a single string of swarf with the thinnest cut I can make, which is a huge difference over my old Cushman (any ideas to re-purpose old chucks?). It's been so good that the 4-jaw barely comes out to play any more. Interestingly, the PB is pumped full of grease to lube and balance everything and that does a good job keeping the chips out, reducing wear to the scroll significantly. Things that cost more than what you want to pay to do right following a big purchase: Putting glass on a rifle, putting tires on a Vette, and putting a chuck on a lathe.
 
If you are seeing 6" chucks in the $75-200 range you are going cheap! I have a 6" Bison 3 jaw that is awesome. The largest error I can see is about .002" runout in certain positions on the scroll. If you buy a good 3 jaw you will not have to switch out to the 4 jaw very often. There may be a lot of machinists who disagree with this but for most of my applications .002 runout is fine, especially if I do all the ops without re-chucking.
Robert
 
Where are PB chucks made now? Buck and Gator are Taiwan or China, TMX and Bison are Poland, different factories, KCM is US but I've heard of inconsistencies. SCA is still Sweden? Opinions on the various chucks? I'm not sure how many of the old names have been bought and are not what made the name famous. Dave
 
Decided to look it up. The Pratt -Burnerd 6" six jaw I bought three years ago cost $300 and another $60 for the back plate. I'm not a big spender, so I had to talk myself into it. It's one of those really good tools that makes me smile when I use it.
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