Capitol wrote:

The reasoning is a bit cockeyed here. The reason you don't want a
drill chuck, is because the drill chuck mechanism cannot handle the high
impact loads without the jaws of the chuck slipping and the chuck
mechanism being damaged. The energy imparted to the tip of the drill bit
in a normal chuck, will to a first approximation, be the same. This is
why SDS drill chucks are specifically barred from impact usage.

This is very true, I was not attempting to suggest you _could_ even use
a conventional chuck, for just the reasons you cite.

However if you could and were to increase the effective mass of the bit
by a factor of (at least) five, you will also increase energy losses at
the point of transfer. You are going to get those losses at some point
in the system, so better they are at the drill to wall interface.


--
Cheers,

John.

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