Posted by Joe Lorenzino on Tuesday, December 30, 2003 at 11:14AM :
In Reply to: OT - Keyless chucks posted by Joe Cimoch on Monday, December 29, 2003 at 8:04PM :
In the machine shop I work in, we have both keyed, and keyless chucks on hand drills, as well as lathes and drill presses. The machinists ALL prefer the keyless type for ease of bit change. The guys in the back like the keyed ones because they can tighten (and abuse) them more. From past experiences, the shop rule is that keyless chucks are NOT TO BE USED for any hole larger than the biggest straight shank bit that will drop into the chuck. That means no bits larger than a 3/8's on a 3/8's drill, and NO HOLE SAWS. The keyless chucks seem to slip on reduced shank bits, and the hole saws lock them up so tight it takes 2 LARGE pipe wrenches to release them, usually resulting in damage to the chuck itself. Ours is a metal only application, so this rule is probably overkill on softer materials. My hand drill at the farm is a cordless / keyless Dewalt which has never given any trouble. J.V.L.