J3 Mount 3/4 KT Chuck?

Never could find any. I have a 3/4" chuck that goes down to 5/32, I think.

Joe, I sometimes use an 18N and when it's mounted and I need to chuck a tiny drill I simply chuck a small chuck with a straight shank. Two chucks, one inside the other. It's very convenient, and I haven't noticed any loss of accuracy as the tiny drills will bend slightly but the tip will pick up a centerpunch and then drill reasonably straight.

GWE

That is exactly the spec of the chuck I'm trying to replace. :)

I was thinking of that... But I'm worried about runout... The application is somewhat critical (.001 is fine, .002 is not) so chucking a chuck worries me... Especially since they are making many, many changes a day.

But if its the only fix...

I am pushing for a 3/4" capacity collet chuck on a J33, but then the end user needs close to 30 collets. Lots of opportunity for "wrong collet" or "where is the collet!?!" moments there...

Regards, Joe Agro, Jr. (800) 871-5022

I think that you are on a hiding to nothing on this one. I can't find any chucks that have that range. I would suspect that the only way for to have jaws that could both successfully grip a 1/32" drill and drive a 3/4" drill would be to have carbide jaws that would probably be small/sharp enough to mark the larger drills.

Collets are a struggle too. ER32 would give you 1/16" to 3/4" continuously in a total of 21 collets but wouldn't go down to 1/32" with out a $pecial one.

Can your customer live with 1/8" shank drills for the small sizes or S&D drills for the large sizes? That would make the chuck or collet selection trivial.

Mark Rand RTFM

I would have to agree on that... Although I've got some 1/2" capacity chucks that go to "nill" and hold a 1/2" shank without a problem.

DA collets... Does my customer's range in 20 steps... But trying to avoid that.

They are already turning the .890" tools down to .750 for the application. I'm afraid I'll traumatize them if I suggest making the smaller ones larger (grin). Circuit board drills are 1/8" shank I think... But that doesn't help much with the chuck I've already got on the table.