Is There An Easier Way For Initial Set-up of 4 Jaw Chuck?

Remember to only adjust out one half of the error at a time, otherwise you will chase your tail tiring to get it centered. Sometimes it helps to mark two opposite jaws with a marker and as others have said work opposite sets of jaws.
 
When I am putting a piece in the 4 jaw chuck (regardless of its' shape) I measure the OD of the work piece so I know its' diameter/dimensions. Then, using 1/2 that diameter, I "eye ball" across two of the jaws trying to align them with each other and then set one of the other jaws off from center using that dimension. Then, after rotating the chuck 90 degrees, I do that same procedure for the next jaw. Having two jaws set this way, I just make sure the opposite jaws are open larger than the diameter and tighten those two onto the work piece.

I've gotten pretty good at this and can typically get a work piece aligned within a turn of a dial indicator (0.100" TIR). It's quick and easy once you get used to doing it this way. As others have said, it does take practice.

Ted
 
I remember from the first times using an independent jaw chuck how tedious it was. Now it is quick and easy.
What helped get there;
-some more concentric rings were added to the face of the chuck
-a 1'' travel indicator is used when possible, or a dti holder with fine adjust feature
-made a couple of stubby chuck keys for the initial steps

How I do it:
Open the jaws just enough to accept the work using the concentric lines to balance position of the jaws.
Tighten the jaws as Ted mentioned above. It helps to use two stubby chuck keys for this step.
Spin the chuck to eyeball for wobble. Tune out any visible wobble.
Set up the dial indicator. A fine adjust really helps so that you can spin the chuck while easing the dti stylus on to the work.
Keep adjusting the high spots down and easing the dti down until there is least run out.
Tighten the jaws gradually and evenly. Practise makes perfect.
 
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Use the indicator smartly--figure out how much wobble is on one pair of jaws, then take 2 wrenches and move the par in one direction (or the other) turning both wrenches the same amount at the same time until the dial indicator reads the average. Switch to the other pair of jaws and repeat.

At this point you will be close enough to use only tightening on which ever jaw reads high.

For parts with a hole in the center, you have to be more gentle on the part or you will distort the part by the forces on the jaws.
 
Thank's for the good ideas. I will try some of them, and of course, practice.
 
The fastest person I have ever seen is Adam on Abom79 (YouTube). Great to watch others do it, helps to put some aspects into place. I watch one epesode where he was challenged by someone to see who could do it faster. Adam won by a margin of around 2:1 time wise.

I thought I was pretty good until I watch Adam. Some of the pointers I picked up watching him I called out above. I also got a chance to put some of these tricks into practice and shocked a buddy of mine as to how fast I could set up a piece on his lathe.
 
The way I learned was to use a long trael dial indicator. Get a reading in line with one jaw. Get a reading in line with the opposite jaw. Adjust the jaws until the dial reads halfway between the first two readings. Turn the chuck 90* and repeat the process with the indicator. That should put the part very close to center. Now rotate the chuck 90* at a time. Tweak the jaws in or out one at a time until the indicator hand does not move.
 
Center in a Four-Jaw Chuck by Using a Shilhouette by Don Peterson.

Machinist's Workshop

email.villagepress.com

I received the above tip/link in a Machinist's Workshop email the other day which may be of some help for you.

Just finished reading all of the posts and it looks like BtoVin83 posted the same link.
 
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