wrote in
:

On Thursday, December 26, 2013 7:32:06 PM UTC-5, 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

If you can tolerate the pin spinning in the hole perhaps quite a bit
I've found drilling rotating pins works if you angle the piece, idea
is to angle the part so the drill spins the pin but off-center, on
'average' there will be a part where the bit is hitting where the bit
surface speed will be larger than the pins.

Maybe you could CA or loc-tite a small metal rod in the drilled end
and clamp the rod in the vise?

Dave

Because the holes are mashed up, getting a good fit will be tricky. I
don't want to spin the pin too much, because I don't want any more wear
in the holes I'm trying to save.

So far, the winner seems to be a double cutter set up.

Doug White