Duane Bozarth wrote:
....
You can get 1-1/4 to 1 tee bushings at many places including Delta.
....

Actually, including Delta in that may no longer be right--I actually
don't know about Delta anymore, for sure. Last time I tried to reorder
some of the 1/2" sash cutters I've used for years I discovered they had
quit making them and was told they (Delta) were getting out of the
cutter business entirely. A quick search on their site found a few 3/4"
supplied w/ 1/2" bushings but didn't see larger ones. That wasn't an
extensive search, however.

Interestingly enough they did show a of sash and cabinet set
consisting of a bunch of the old 1/2" cutters that were discontinued
that I don't recall having seen before--whether an order could actually
be placed and shipped, I don't know.