"Pete C." wrote in news:52bccd9c$0$29568$862e30e2
@ngroups.net:


Doug White wrote:

The collegiate pistol team I help coach has two Russian target air
pistols that have broken cocking linkages. I have replacement parts,
but I need to disassemble a linkage that has a swaged pin in it. The
ends of the pin are even with the sides of a piece I need to rescue
undamaged. I had originally planned on drilling/milling out the
center
of the swaged part enough to press the pin out, but I discovered that
the pin is free to rotate. There's nothing exposed enough to hang
onto
that I don't need to largely cut away.

I can probably grind out the swaged bit VERY carefully with a Dremel,
but it's going to be tedious & fussy.

The pins are about 5/16" in diameter, and each end has a shallow
drilled
out section. It looks like they pressed ball bearings into the ends
to
spread them. The linkage the pin goes through is countersunk on both
sides, so the swaged bits hold everything together.

There a picture he

http://www.pyramydair.com/blog/image...inkage-web.jpg

The pin is the large one with the dimple just left of center in the
image.

The only way I can think of to physically hang onto the pin is to
make
an expanding collet that goes into the drilled out pocket on the far
end
of the pin. That is going to be tenuous at best, and it's a lot of
work
to fabricate for a high likelihood of failure.

One other option would be to crazy glue everything together, mill out
the swaged bit, and then soak it in acetone until the pieces free up.
That assumes the crazy glue can handle the machining forces.

Before I drag out the Dremel, does anyone have any better sugestions?

Thanks!

Doug White

How about setting up so the opposite side is pressed against a
multi-flute countersink to act to stop the pin from turning?

I thought about that. I suppose if I put a cutter on both ends, one
fixed & one under power, one of them will do the job before the other
one does. Or both will be the same, I don't care. My only concern is
not being able to see what's going on underneath, and fixturing it so it
can't scoot sideways.

Doug White