I bought a set from ToolSatan, all from the same manufacturer to hopefully
get compatibility.

Mexco DCX90 cor drill and Mexco 250mm SDS adaptor pack.

The guide drill in the pack is a taper fit. 10mm drill.

I don't get this taper fit thing unless there is something wrong with the
one I got.

By hand, I can push it in until it grips and needs the release rod thingie
to make it pop out again. However although the taper is engaged through
all the hole (because the bottom is just about sticking through to the
release hole) it doesn't seem to grip enough to drill effectively.

When I use the core bit, then pull back, the drill bit is left in the hole.

I suspect from the markings on the shaft that it is not turning much if at
all. I would expect that if it was properly engaged then I would have to
use the drift to get it out.

No biggie at the moment because I am drilling a guide hole with an SDS
drill bit before using the arbor and that seems to be working.

Just wondering what would happen if I didn't use an SDS bit to make a
guide hole first.

Instructions just say "Insert A-taper bit into adapter". Nothing about a
sharp rap on the top to get it seated or anything.

It is so long since I did any core drilling that I can't remember the fine
detail from last time.

Cheers



Dave R


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