How to drive large auger bit with 7/16" Powerdrive Hex shaft

[Ronald Blue]

The points should fit in between the chuck jaws as mentioned before. True, you can't fit a 11/16 point to point inside a 5/8 hole, but a chuck is different.
I'm in the camp that says you have a metric chuck that is smaller than 5/8 or it's not open all the way and could use some WD-40 or whatever you like to use to clean it up a bit...... It should work.

I just checked my 1/2" chuck and it will accept 1/32" over 1/2". That's what I expected. Apparently 5/8" chucks are different? Not to my recollection from my machinist/tool and die days. I give Joe the benefit of the doubt that he knows what he's talking about. I think he can knock the points down and it will still run true and chuck up securely.

[Ronald Blue]

EXCEPT that the end of the chuck has a circular hole that the jaws of the chuck move in and out of. If that hole is 5/8”, there is no way a hex shaft with a point to point width of larger than 5/8” is going to fit, as you said. Can’t see how a chuck with a 5/8” opening is different than a 5/8” hole...

Perhaps the OP can enlighten us a little more.

My point exactly Bill. A chuck isn't different. They still have a hole that is the final limiting factor in what will chuck up in it. In my experience you can get usually a 1/32" larger than the rated capacity. The hole is what prevents going any larger.

[Joe Jensen]

Checking back in. The 5/8" chuck I have will accept a 5/8" diameter round and no larger. The 1/2" chucks and the 3/8" chucks are also limited to those sizes. Nothing bigger than 5/8" will fit.

I gave up and ordered another bit that has a 1/2" round shank. My bad in the first place for not noticing the shank when I ordered. I seriously considered welding (epoxy was a better idea) a socket on the shank but I was worried about runout and I also need to be able to pull the bit back out of the wood while running to clear chips so I figured I'd have to weld a cut off extension onto the socket.