Proper reinstallation of a 3 jaw scroll chuck??

[dirtcrasher1]

Sometimes I open my chuck too far and one falls out, or they all do.

Of course jaw 1 goes in #1 on the chuck and so forth.

The distance from the edge of a jaw to the chuck gripping area on all three are different lengths so they will end up matching once installed correctly.

I always kinda wing it and by turning the scroll I can get them in place. Sometimes it takes pulling one out and spinning the scroll until it drops in at the correct place.

What is the proper procedure? For a 3 jaw scroll chuck.

Thank you!

[Harold_V]

The distance from the edge of a jaw to the chuck gripping area on all three are different lengths so they will end up matching once installed correctly.

I think that if you examine the jaws closely you'll discover that the lengths you mentioned are all identical. The usual condition is that the jaws are indexed 120° so the teeth that contact the scroll are offset the appropriate amount so the jaws center. For that reason, they must be installed in the correct slots, at least as they relate to one another. Said another way, it's possible that the #1 jaw could be installed in either the #2 or #3 slots on the chuck body, so long as the rest of the jaws are installed in proper sequence.

What is the proper procedure? For a 3 jaw scroll chuck.

I'm not sure there's a "proper" way, but my procedure is to first remove all jaws, then to blow out the body. Because of the design of the chuck, chips can enter the scroll area. They generally do no harm, although they can make turning the scroll difficult if they get wedged between the scroll and jaws. By rotating the scroll as air is played in each of the three slots, free chips are removed, eliminating the problem.

I then turn the chuck so the #1 slot is at the top, at which time I turn the scroll until I see the leading edge of the thread. It is backed up enough to permit the thread to engage the #1 jaw, which is then installed. I then turn the scroll so it advances towards the #2 position, and repeat the procedure, installing the second jaw. Repeat for the third jaw and the chuck should be properly assembled.

Some will argue that air has no place on machines, and that a chuck should not be blown out. I have no quarrel with them if that's what they choose to believe, but I've been doing it for more than 50 years and have yet to discover a reason I should not. Hard to argue with success.

Harold

[dirtcrasher1]

Thank you, got it right 1st shot.