"Ned Simmons" wrote in message
...
In article , no-
says...
I happen to have a nice Nikken metric boring head that was designed to
fit a
26mm BT-flange holder. This boring head has a 26mm dia x 26mm straight
cylindrical shank with two radial holes at 90-deg to accept locking set
screws or pins.

Of course, my mill doesn't have a BT spindle; it has an R8 spindle. So my
idea was to use an end mill holder as an adapter for this boring head.
...


It'd be a lot easier to turn the shank down to 1" to fit an
end mill holder, or 3/4" to fit an R8 collet, than to bore
the holder.

I realize that's an option. But I am opposed to cutting or grinding the
shank on this beautiful precision tool, not so much for practical reasons,
than on principle. The way I look at it, an adapter is a consumable part
that is subject to change over time (as a tool migrates from machine to
machine, or as the adapter wears). So it makes more sense to me to modify
the adapter than it does to modify the tool.

- Michael