The Delta Mortisers do not fit all drill presses. I bought one a few years
ago and returned it after it would not fit my older Craftsman machine. I
subsequently used one on a friends machine. Impressions:

1) It is a compromise compared to a stand-alone mortiser. It will do the
job but the shorter handles on most drill presses require quite a bit of
force to achieve a mortise in hardwood.

2) Attach and teardown takes time and disables the drill press as a drilling
machine during mortising. This can be overcome by planning but still a
nuisance.

The mortiser does its work by leading in with a drill bit and squaring the
corners with the intergal square chisel. For occasional mortising you can
do the same thing in two steps. Attach a fence and carefully drill a series
of holes of the correct width; then square corners and clean excess between
holes with a sharp chisel. If you find yourself mortising more a dedicated
machine is a good investment.

By the way, Harbor Freight sells a dedicated machine for about $100. Not a
jewel but it cuts square holes and comes with decent chisels. The hold down
hardware is crappy but the machine provides a better option than the drill
press attachment (IMHO).

RonB

RonB


"Toller" wrote in message
...
I just got a LN 12" Delta at an auction for $80.

Ebay has a mortising attachment locally. Do they work, or are they just
aggravation?
I have never actually made a motise, so it is hard to say how many I will
be doing.