[Shop-talk] tolerancing a interference or friction fit ???``

[Randall]

> << Will it help to freeze the bushings before inserting them? >>

Not gonna help, at least not enough, IMO.  Coefficient of thermal expansion
for steel is only .0000073 inch per inch per degree F.  So assuming you can
get a 600F differential in temperature (ie arms heated to 600F, bushing
cooled to 0F), that's still only about a .005" improvement (.0000073 * 1.25
* 600).  That still leaves .005" to .013" difference in diameters, which is
still way too much.

-- Randall