Apparently gear cutter holders [right angle] were about as common
as fly cutter holders at one time. this is no longer the case.
As a project in our machining class we cut some change gears and
had to make our own tool holder. You can use a boring bar but
the tool is held above center so you will need to grind 1/2 of it
away to get the tool on center to generate the correct profile.
If you want positive rake or hook the remaining material gets
very thin. Law's book has detailed plans for a holder. One tip
is to use a shoulder bolt for the shank by turning the head down.
You can drill, tap and counter bore for the shoulder bolt and
then loctite it in place. Then locate the tool slot etc. from
the shank. We also had good luck using a #2MT drill chuck shank
with a 1/2 fine thread as a shank. Only the tang was hard and we
were able to cut the shank to the correct length for use with a
drawbar. Modified shank was then drilled and tapped to fit our
drawbar. This gained us about 1 inch of headroom.

GmcD



On 10 Aug 2005 23:48:00 -0700, "himog" wrote:

Grant Erwin:
Many many boring bars have square holes, one at 90° and one at 45°.-


None of the boring bars I have seen have holes in them for holding
cutters.

Many of the boring heads I have seen have holes in them for holding
cutters.

I have no need for a tool holder with the adjustment capability of a
boring head for holding single point cutters at right angles to a
spindle. I have need of a holder which can simply hold the cutter at a
right angle to the spindle for simple one-off form cutting.

Boring heads cost five to ten times what fly cutters cost, and I have
no need for the extra features paid for by that difference.