Replacement drill chucks

[WilliamTO-35]

I have three Sears Craftsman cordless drills . I've owned them for at least 8 to 10 years . I like them, I have extra battery packs, and I want to keep them . But, two of the three drills are having trouble gripping the drill bits without spinning and tearing up the bit. I've cleaned the chuck teeth , and visually I can't tell what's wrong with them. But, I'm giving up and buying replacement chucks . The chucks mount on a 1/2 - 20 spindle , with the center left hand thread machine screw in the middle. Without spending a small fortune on Jacobs chucks, what brand of chuck ( 3/8 inch capacity) do you recommend ?
Thanks.

 

[bcp]

You can find bits with 3 slight flats on the shank. You have to look closely as it might not say on the packaging. And there are bits with 1/4 hex shanks, too.

Bruce

 

[WilliamTO-35]

bcp- Thanks for your suggestion. It's true that hex shanks won't spin, and driving screws with hex bits works fine . But, I have a large collection of conventional round drill bits ( hundreds of them) in carbide, cobalt, high speed, and Harbor Freight metal (an undefined and variable alloy) , and I need to be able to use them without damaging them.

 

[GLyford]

Are you looking for keyed or keyless?

The last time I changed out a chuck, it was because I managed to kill the gears in an ancient B&D corded drill. I found a similar corded drill in a thrift shop, and did not realize when I bought it that its chuck was bad. I never did get the good keyed chuck off the old drill, but I did get the keyless one off of a HF cordless drill that didn't have any good batteries.

Cheapest option I have found for 1/2-20 is the 1/2 "Jacobs" at HF:
1/2 in. Jacobs(R) Keyed Chuck
I have picked a few of these up to have on hand over the years, but haven't actually used them (the drill above was also a 3/8 like yours).

I have not used the next cheapest option, which is the Ryobi at home depot. This is also a 1/2" chuck.
Ryobi 1/2 in. - 2 Teeth per in. Drill Chuck and Key-A1KC31 - The Home Depot

I think your absolute cheapest option may be to buy a cheap cordless drill with no/bad batteries from a thrift store/junk shop/pawn shop/flea market/tag sale.

 

[Jesse masterson]

 

[stuckmotor]

When I work my way around the chuck using the key in all three holes, have less slippage.