Originally Posted by
Mason
I'm having a massive memory failure right now. what is the size of the arm hinge pin? trying to find a reamer!
If you're talking about an Associated front end the upper arm pin is + or - .079". This makes sense because .078 is a common wire size, plus add the oxide coating.
Unfortunately this isn't a common reamer size. I'm looking at the Victor Tools site and see that this is a bit of a "void" area, size-wise. A #47 reamer is .0785" while a #46 is .0810". Realistically, though, the #46 would probably be about right as you aren't really wanting an interference fit. In fact the approx .015-.002" oversize may not be enough--that would take a bit of experimenting. A #45 reamer is .0820", then it's a pretty big jump to .0860 for a #44.
These reamers are under $7 each, I'd be inclined (and am now that you've got me thinking about it) to pick up one of each.
Something I would do would be to ream the upper arms THROUGH the upper arm mount. Something I've noticed (as have, I'm sure, you) is that even if you get the upper arm holes sized properly so they move freely that they can then bind up once the pin is run through the upper arm mount. I'm sure it has to do with molding tollerances and the upper arm mount hole bore not being exactly parallel with the upper arm hole bores.
The page at Victor with the straight flute reamers is
http://www.victornet.com/cgi-bin/vic...%2C1562%2C+629
This is where I order all my taps, etc from. Their selection and service are excellent, and as I recall their shipping price is fairly reasonable too.
Scottrik