I found myself in a similar situation a couple of months ago. I did all
the stuff you did, buying the 4 way key that didn't work, looking stuff
up in the catalogs, Machinery's handbook, etc.
In the end, the "Key" was simply to measure the diameter of the key
hole in the chuck. I then looked it up in (I think) the MSC catalog and
bought it. It fit.
Of course I now have enough other chuck keys so I could go into
business for myself!

Pete Stanaitis
----------------

WoofWoof wrote:

Can anyone direct me to a chart for chuck-key dimensions. I want to
order a few but the catalog lists about ten or a dozen sizes and I've no
idea what mine is. Besides, a chart would look good on the shop wall (:-).

I've done google searches till I'm blue in the face and even located a
website for Jacobs ( http://www.jacobschuck.com/ ).... possibly the most
useless site I've ever seen.