On 13/08/2020 21:22, Jeff Layman wrote:

I used an ordinary B&D hammer drill before using an Energer SDS Plus
drill. That drill comes with an "ordinary" chuck as well as an SDS one,
except that the ordinary chuck has the same SDS Plus shaft as the SDS
chuck has. So I assume it is designed to take ordinary drill bits to use
in SDS hammer mode. I think I would have noticed if the drill bit was
blunt before using it with the SDS drill, as I had to remove it from the
B&D chuck first.


The ordinary chuck is so you can use wood bits, hole saws, etc, with the
hammer turned off. It won't work for hammer action.

Bill