# 4 Jaw Chuck



## NCjeeper (Dec 12, 2015)

Watching Adam's videos (Abom79) got me motivated to remove my 3 jaw and install my 4 jaw and use it. Still cant dial in the material very fast but Im working on it. Any of you guys use your 4 jaw as our normal chuck?


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## David S (Dec 12, 2015)

Yes...sort of.  I have a 3 jaw Jacobs spindle chuck that goes up to just over 1/2", anything larger is my 4 jaw independent.  With two keys I can centre pretty quickly for most work and pull out the dial indicator for real accurate stuff.  Small accurate stuff I use ER collet system.

David


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## Chipper5783 (Dec 12, 2015)

4 jaws chucks work great.  Certainly for certain irregular shapes, or if you need a piece offset from center - they also hold better, less tendency to distort hollow work.  With a bit of practice, you'll get much quicker.  I still recall my first awkward efforts (probably took me 15 minutes) - now it is a routine task (perhaps it takes a minute?).

I have not used the 2 key method (I'm used to a method that works well for me).  Number the jaws, locate your dial at the top of the work piece (the mag base on the cross slide so you can move the whole dial back and forth to get the pointer on the high point), then work the jaws in pairs (i.e. get 1-3 close, then work 2-4, repeat), ignore the dial reading between the jaws - just dial the 4 quadrants (the space inbetween will sort itself out).

Regards, DavidC


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## joshua43214 (Dec 12, 2015)

I use the 4jaw more than the 3jaw.
I never understood why people avoid them so much.
DavidC laid it out perfect. They hold better, distort less, and have less rotating mass and stick out.
Dialing in to about a thou takes maybe a minute, just work jaws in pairs. If I really mess up the initial centering, I use two keys to get it close. Then I just use one key. It is not rocket science, you just tighten the "high" jaw by 1/2 half the runout.

I do use my 3jaw, I just find the 4jaw more useful over all and so it tends to live on the lathe more than the 4jaw. Mostly I use the 3jaw when I am cutting parts off the end of a long bar that is run through the headstock. Hard to beat a 3jaw in that application.


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## mksj (Dec 12, 2015)

Kinda a little of both depending on the project. If I was removing a piece frequently, 4 jaw gets to be a pain unless you use it a lot. I really like my 4 jaw combination, kinda the best of both worlds but they are very uncommon.


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## Uglydog (Dec 12, 2015)

My 10inch Powermatic/Logan came with a 4jaw. That's all I had. 
Never did figure out the two wrench thing.
Now the only reason I keep the 3jaws for my other lathes is that it may make the lathes more saleable- someday....

Daryl
MN


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## British Steel (Dec 13, 2015)

Call me spoilt, I have three 4-jaws of various sizes (the 10" Pratt-Burnerd with matching to lathe serial number stamped on the back..., a 8" Fuerda and a 5" Bison), swap them to suit the work as the lathe spindle has D1-5 engagements, not a thread.
I find the 4-jaws pretty quick to centre to within a thou" or less with a decent DTI (finger type, not plunger - I don't use two keys either) and use them in preference to the 3-jaw (an 8" Pratt-Burnerd, also matching s/n) even for quick jobs, although it's very good for a 60-year-old chuck, within a couple of thou" still! It may wind up permanently attached to a rotary table?

 I also have the rare-as-rocking-horse-droppings native collet set (Holbrook parts are more than scarce and generally don't match up to any others!) and drawtube for up to 7/8" for less-than-tenth accuracy...

Anything really awkward goes on a faceplate firmly clamped, that way if it clears the ways it can be turned  Many seem intimidated by faceplate work, but with some attention to clamping, balance and *keeping the speed down* it's a good way to hold really oddly shaped work that you'd otherwise have to bore on a mill.
Even more run from between-centres machining, but I think it's the only way to reliably turn anything that needs to be taken off the lathe and e.g. checked for a bearing fit or measured. Does shallow tapers nicely too!

I WOULD like a 6-jaw self-centring chuck for thin-walled tubes etc., but I haven't  found one in my price range yet... and I need to make a D1-5 spindle nose to go on one of my rotary tables!

Dave H. (the other one)


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## mattthemuppet2 (Dec 14, 2015)

had only a 4 jaw for 2 years, so it's nice to have a 3 jaw at last  That said, it's a very handy thing to have when you need it.


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## NCjeeper (Dec 14, 2015)

Used it today. Got the stock dialed in in only a couple of minutes. I getting better with practice.


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## tomh (Dec 15, 2015)

My first encounter with a 4 jaw was in the 7th grade. 
We had to remove our project at the end of class, If we didn't  the next day we had to get it out of the trash, so we got good real  quick.    Sink or swim   

My first encounter with a 3 jaw was  like how does this thing work no mater which hole I stick the key in all the jaws turn together   ROLMAO  

Just remember    tighten on the high       loosen on the low  

Numbering  the jaws may reduce the  chance of  confusion  also.

Tomh


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## NCjeeper (Dec 15, 2015)

tomh said:


> Just remember    tighten on the high       loosen on the low
> 
> Numbering  the jaws may reduce the  chance of  confusion  also.
> 
> Tomh


Roger that.


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## dlane (Dec 15, 2015)

In that pic it dosn't seem to be able to hold smaller od parts with those jaws


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## zmotorsports (Dec 15, 2015)

My 4-jaw isn't my "normal" chuck.  I generally have my 6-jaw on the lathe, however, I do use my 8" 4-jaw quite a bit.  Much more than on my previous lathe because the D1-4 mount is so much more user friendly when it comes to switching chucks.  I also use my faceplate a lot more than my previous machine.

I too have myself dialing in my 4-jaw quicker each time I use it, which is probably why I find myself reaching for it as much as I do.

Mike.


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## kingmt01 (Dec 17, 2015)

I seem to need which ever Chuck isn't on the lathe. I mostly use the 4 jaw tho. If it is a one time setup or a short job I use what ever is on there. If it needs to be exact I use the 4 jaw. If I have to pull the part I take my sharpy & mark the piece & jaw then only loosen two jaws. Putting it back I tighten the two I loosened. Usually with no correction needed.

I use the three jaw when I'm going to be in & out a bunch before I'm done & have a good bit of tolerance.


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## autonoz (Dec 17, 2015)

Here's one of my four jaws. Can't even lift it. Don't have a use for it. 24" and is extremely heavy. Picked it up at an auction because nobody else wanted it.


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## Uglydog (Dec 17, 2015)

autonoz said:


> Don't have a use for it. 24" and is extremely heavy.
> 
> 
> 
> ...



Looks clean.
What is the back?

Daryl
MN


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## chips&more (Dec 17, 2015)

I can count on one hand the times I have used a 4 jaw chuck in my shop in the last 40 years. When I do use it, there is no substitute, but it’s rare. If you want to offset a project in a three jaw. Just put a shim between one of the jaws and the work. I have used that method many a times when making cam action levers for Levin lathes. No dial indicator needed, you know the offset (trig it) because of shim thickness …Dave.


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## autonoz (Dec 17, 2015)

Uglydog said:


> Looks clean.
> What is the back?
> 
> Daryl
> MN


It is clean and jaws are in great shape and move freely. It was put in my truck yesterday and it is still there. I can not lift it to see the other side. LOL! I will pull it out this weekend and post a picture of the back.


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## kingmt01 (Dec 17, 2015)

That wouldn't fit on my lathe & it probably couldn't turn it if it did. I'm not even sure it would even support the weight.


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## Andre (Dec 17, 2015)

My 9" 4-jaw is my only decent chuck. I have a smaller 3-jaw Cushman, but it needs a rebuild and the jaws need to be ground.


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## JimDawson (Dec 17, 2015)

autonoz said:


> Here's one of my four jaws. Can't even lift it. Don't have a use for it. 24" and is extremely heavy. Picked it up at an auction because nobody else wanted it.
> 
> 
> 
> ...



If you have no other use for it, it would make a great grinder base.  Just clamp the support column into the jaws!


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