"KyMike" wrote in message
oups.com...
I need a way to use 1/8" dia. straight shank cutters in a Gorton
pantograph engraver with a taper socket spindle. A ready made collet is
very expensive to buy new, so I was considering trying to make one from
drill rod. The problem is that oddball Gorton spindle taper. Is there
any simple, accurate way to set up to turn this without all the trial
and error? Is it even reasonable to attempt to do this without some
sort of precision grinding equipment? I'm not sure what the spindle
speeds are since the data plate with the information is missing and
they couldn't help at Gorton, other than to tell me the machine (a 3-F)
has not been made since the 1950's, but it takes almost a full minute
for it to come up to full speed and so I'm guessing it could be
somewhere around 15,000 rpm or more. Any advice appreciated.
Mike

Making something you can spin at that speed requires a little thought. I'd
be inclined to make an adapter that takes a collet for a Dremel tool. You'd
want to make it of mild steel (not drill rod) or even brass. I've never had
very good luck using the compound. I prefer to offset the tailstock, put
the faceplate on the lathe, mount the work between centers and drive it with
a dog. The nice thing about this approach is that, once you have the
recipie down, you can repeat it by simply starting with pieces of stock that
are the same length. I made an alignment bar that is just about the maximum
lenght the lathe can hold out of 2 in. diameter aluminum with the last
couple inches on each end cut and polished to the same diameter. Then I can
put a dial indicator on the tool post and it makes setting the offset (and
returning the tailstock precisely to center) very easy. You simply
calculate the offset required to give you the taper you want, given the
length of your stock.

Jerry