Three Jaw Independent Chuck

Looking for any information on the use and and avantage of the a Three jaw chuck.it's purpose.

I have one.

any coment appreciated.

Doug in Canada.

Doug,

Somewhat confused:

Chucks are typically either independent or self-centering

.... and three-jaws are usually [as Jason indicates] the self-centering type.

Do you really have a three-jaw independent ?

If so; could you please post details or a photo.

MichaelG.

Edited By Michael Gilligan on 12/08/2013 09:34:06

Michael

He doesn't say that it is a 3-jaw independant just that it's a 3-jaw. If it is a self centering then, its use is as Jason states. The only variation of that I know of is the Grip Tru which is commonly ( although not exclusively) a 3- jaw chuck.. So Doug - is this a 3-jaw self centring chuck which which has an additional adjuster next to each jaw? If so what you have is a chuck to be cherished!

Here is a pic.

You will see that, alongside the normal hole for the chuck key is socket for a hexagon key. This allows the micro adjustment.. If this is like your chuck just reply here and I will post the adjustment instructions.

Regards

Norman

Norman

The title of the thread mentions "independant".

Jim

Could possibly be a 3-jaw combination chuck where each jaw can be adjusted separately and then a single key will move all three. Used for repetition of holding a round object off centre eg if you were making loads of eccentrics.

J

.

Norman,

As per Jim's comment

MichaelG.

OK Michael - I'm in error here - I've never come across the combination chuck referenced by Jason so the only one to fit the bill, to my knowledge, was the Griptru. Hopefull we will be enlightened eventually. ( Although I've spent much of my life, fruitlessly, awaiting enlightenment)

Norman

Edited By NJH on 12/08/2013 12:38:50

Hi Norman,

By way of some enlightenment ... whilst we wait for details from Doug

You might like this.

MichaelG.

Thank's Gentleman for your interest.

Some old very experianced Machinist have observed this Chuck with their Jew on the floor, one said that he feels that he had seen one while in the Navy but only vague about it.

This I beleave to be American and may possibly be associated with a Rotary Indexer for possibly Ecentric and Cam Grinding/Cutting??

Hear are the Photo,s as requested.

The only reason I use a three jaw chuck is for holding hex bar... I use a four jaw self centering for round and square bar and a four jaw independent for placing the workpiece where I want it rather than where the chuck wants it

Steve

I also use my four jaw self centering for holding hex. The only advantage my three jaw has is the larger hole in the centre for allowing larger diameter work to be held further inside the body of the chuck, rather than having to stick out.

Jo

Gentleman I have mostly every chuck avaible, this one is close to being an odball.

My interest is in the Practical Theory and purpose design of this Chuck and it's purpose use.

Your technical theries and history of this chuck is required and appreciated.

Doug in Canada

My Mistery is Solved.

Many Thanks to those gentleman that responded professionly and constructivly, I particuly apreciate the input of discussion from both Michael and JasonB eith a high 5 to Michael for the look at This, that forced me to disect the Chuck and solved the mistery.

Thanks to all from Doug in Canada.

My

A fabulous find, Doug ... and thanks for the great photos.

We've all learned something today ... which is why we are here !

MichaelG.

Doug,

You have to ask questions about its work holding accuracy, it is not only depended of the accuracy of the thread of each jaw, but also of the gearing, In a normal scroll chuck the accuracy of the gearing has no part ín the centering of the workpiece. Niko.

Doug,

Here is an intriguing PostScript

MichaelG.

Doug,

One more gem for you.

Scientific American

MichaelG.

Of course it would have been easier to turn the key to see how it worked rather than pull it all apart