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daved20319
05-27-2012, 12:18 PM
The HUGE difference in cost of 4 jaw independent lathe chucks? I'm looking at plain back, 8" chucks, and the prices range from just over $100 to almost $600, maybe more! And that doesn't include the back plate.

So what does that extra $500 buy me? I guess I'm whining a bit, I really need to replace my 4 jaw, I don't want to have to spend $500 to do it, but I also don't want to throw away $100 on another POS like I already have. I could really use some guidance here, thanks.

Dave

Duffy
05-27-2012, 12:34 PM
I will try-a little bit! First, chuck bodies can be grey cast iron, which is cheap to buy and pour and machine. Then there are "semi-steel" bodies. I THINK that they are a type of ductile iron and thus require a heat-treating step before machining. Finally there are steel, either cast or forged. Each of these processes are much more expensive. These choices will result in quite a range of prices and we have not touched on machining, either for precision or finish.
Now, how about the "moveable bits?" Quality of the screws-are they ground and hardened, or machined and ??? Are the jaws precision ground and hardened as matched sets or are they a "toss fit" of whatever is on the table?And on and on and on- you get the idea.
Personally, as a hobby worker, I believe that just about ANY "cheap and dirty" $100.00 4-jaw will hold to any limits that I can work to, and since it is only used once in a blue moon, it will not wear out.
A LOT of different strokes for different folks!

dian
05-27-2012, 12:42 PM
500$ buys you concentricity between the gripping axis of the chuck and the spindle axis.

i myself would not dare to buy a 8" chuck for under 1000$. unless you know what you are getting. i have a noname 4 jaw independent chuck and never use it. fortunately it is small and was unexpensive.

dian
05-27-2012, 12:45 PM
duffy, we say: there is a seat for everybodys ass.

philbur
05-27-2012, 01:08 PM
If you list why you think the $100 one you aready have is a POS then you will know where the extra $500 goes.;)

Phil:)


The HUGE difference in cost of 4 jaw independent lathe chucks? I'm looking at plain back, 8" chucks, and the prices range from just over $100 to almost $600, maybe more! And that doesn't include the back plate.

So what does that extra $500 buy me? I guess I'm whining a bit, I really need to replace my 4 jaw, I don't want to have to spend $500 to do it, but I also don't want to throw away $100 on another POS like I already have. I could really use some guidance here, thanks.

Dave

lynnl
05-27-2012, 01:23 PM
duffy, we say: there is a seat for everybodys ass.

:D:D That's funny! :D Had not heard that analogy before.

Thnx for the laugh!

flylo
05-27-2012, 02:10 PM
500$ buys you concentricity between the gripping axis of the chuck and the spindle axis.

i myself would not dare to buy a 8" chuck for under 1000$. unless you know what you are getting. i have a noname 4 jaw independent chuck and never use it. fortunately it is small and was unexpensive.

dian, I have a chuck for $1000 & will name it anything you want! LOL. I just bought a import floor drill press named "Tom & Liz" hohestly that is the brand name. My wife is Elizabeth do know I can say I'm going to the shop to drill Liz.

toolmaker35
05-27-2012, 02:56 PM
dian, I have a chuck for $1000 & will name it anything you want! LOL. I just bought a import floor drill press named "Tom & Liz" hohestly that is the brand name. My wife is Elizabeth do know I can say I'm going to the shop to drill Liz.

LOL!! Whew! Now I've got to wipe the iced tea I was drinking off of my monitor...

Dr Stan
05-27-2012, 03:48 PM
Before you drop $1000 on a new chuck try to find a good used one. Lost Creek Machine and Anderson Tooling are two sources that come to my mind.

Forrest Addy
05-27-2012, 05:32 PM
Duffy daid all I have to say on the topic. You don't indicate your level of use. hobbyist, serious home shop, light commercial, or daily production. If your in the lower brackets spendig extra money on a 4 jaw doesnt buy you much but heavy service durability.

My everyday 12" 4 jaw is a Bernard. I've had it for 40 years about 30 of which were three nights a week and a weekend day in the shop so its amortized first cost at about $8 a year,

It's hard to wear out a 4 jaw. They're usable for generqations unless you grip scaley forgings and castings for toughing on a daily basis. Even then you can re-tooth the jaws until you get below the case. Wear and clearance in the jaw slots isn't really an issue because the forces of the grip tightens the jaws against the slots negating wear.

A nice tight new chuck is better to work with but old and battered 4 jaws are usable if nothing else as Christmas tree stands.

RalphWilson
05-27-2012, 06:57 PM
the money differences between the chucks are manly the quality.
I recommend a BUCK Chuck , I have used several 4 jaw chucks and just the quality of all of the parts that make up the chuck just work better.
You can get others on ebay for around $150 used plus shipping.
beware of the self centering 4 jaw chucks, thats not what you want.
You want to have 4 independent jaws.

Enco sports two inports one for $119 and another one for $191.
A buck will cost $800 and if you are gonna make 10 times back in profit from your lathe , then I would get the Buck.
But if your gonna make ten parts a year then go with the enco.

Orrin
05-27-2012, 07:31 PM
I made the mistake of buying a cheap four-jaw chuck, thinking that independent jaw adjustment could compensate for any inaccuracy. Boy, was I ever wrong! Three jaws are parallel and the fourth points toward Afganistan. It is impossible to use for any purpose except help fill up the scrap barrel.

Spend the money.

Orrin

oldtiffie
05-27-2012, 08:12 PM
The HUGE difference in cost of 4 jaw independent lathe chucks? I'm looking at plain back, 8" chucks, and the prices range from just over $100 to almost $600, maybe more! And that doesn't include the back plate.

So what does that extra $500 buy me? I guess I'm whining a bit, I really need to replace my 4 jaw, I don't want to have to spend $500 to do it, but I also don't want to throw away $100 on another POS like I already have. I could really use some guidance here, thanks.

Dave

My guess is that the seller/trader sets it at a price that he can make a profit at and that the market buys enough of them to keep turning over those chucks at that price.

Market forces.

J Tiers
05-28-2012, 11:02 PM
Now that everyone has pointed you to the $600 one.......

I bought a Bison 4 jaw several years ago, and that thing has been very good. they have gone up in price, but they are still at the lower end of the good chucks, and I don't believe that a "Danaher" Buck chuck is going to be very much better than a Bison. if it is better at all.

mine is allegedly semi-steel, neither plain CI nor steel.

Paul Alciatore
05-28-2012, 11:40 PM
Duffy daid all I have to say on the topic. You don't indicate your level of use. hobbyist, serious home shop, light commercial, or daily production. If your in the lower brackets spendig extra money on a 4 jaw doesnt buy you much but heavy service durability.

My everyday 12" 4 jaw is a Bernard. I've had it for 40 years about 30 of which were three nights a week and a weekend day in the shop so its amortized first cost at about $8 a year,

It's hard to wear out a 4 jaw. They're usable for generqations unless you grip scaley forgings and castings for toughing on a daily basis. Even then you can re-tooth the jaws until you get below the case. Wear and clearance in the jaw slots isn't really an issue because the forces of the grip tightens the jaws against the slots negating wear.

A nice tight new chuck is better to work with but old and battered 4 jaws are usable if nothing else as Christmas tree stands.

I have to agree with most of what Forrest and Duffy said, but with a few exceptions.

First, I did get a heavily worn, six inch four jaw with my SB lathe. It is OK for some work and I have used it, but the jaws are loose in their T slots and contrary to the statement that tightening them will take up the slack, when you tighten them they tend to cock so that the tips of the jaws are spread wider than their backs. This makes their grip less firm and it is even possible that the work could move while machining. This is worse with short work pieces which do not reach the back of the jaws. It may be possible to improve this situation with new jaws, but then the slots themselves may be worn so that would be a gamble.

It also may be possible to improve this worn chuck by grinding the faces of the jaws, much like you would do on a three jaw. Like grinding a three jaw, you would have to insure that the jaws are tightly closed against a ring to have them cocked at the same angle they will be at in use.

I purchased an import four jaw, also six inch on sale for well under $100. I was very surprised at the quality. I can not speak at the long term durability as I have only used it a limited number of times. I use it primarily on my RT. I plan to get a Bison at some time in the future for the lathe. I doubt that in my home shop that I will ever need a better one, but if I do, then I will address the shortcomings of the Bison at that time and look for one that promises to correct them.

I do have a Bison three jaw with interchangeable jaws and I have found it to be excellent.

oldtiffie
05-29-2012, 06:44 AM
All chucks are long or short term replacement items eventually and as such are a replaceable/consumable item.

Chucks via their keys etc. should not be hard tightened down - and especially no "cheaters".

Wilful abuse will bring "wear" problems eventually - same applies to vises.

A "worn" (abused) chuck jaws and their guided/slots will have the same up-lift as do moving jaws on a mill vise.

Once the damage is done it is irreversable.