Quote Originally Posted by dnmilikan
[i][b]The term "machinists press fit" means that with .005 a human being could not physically insert one piece into another without the use of mechanical aid in the form of a hydraulic or mechanical press.
Don, Ed, you're both right.
Don, I think you left off a decimal place. A .0005 interference would be appropriate for a pin in the 1/4" range or smaller, which is about the size I imagine your registration pins to be.

Ed, you're right, a .005 interference would certainly bust things apart up to a certain size.

Old machinist thumbrule for press fits: .0005" for less than 1/2", .001" up about 1-1/2", then add .001 for every 1" larger. A .005 interference would be appropriate for a 5" diameter.

Caution: Thumbrules are known to vary from source to source.

Alex (Once trained in Wichita area shops)