Slip fit

[bytes2doc]

I'm in the midst of making the motion works on Bill Smith's skeletal clock design. He states there is a slip-fit of the cannon pinon onto the center arbor. I take this a a nice fit but not tight. That being said, then the cannon pinon would just spin on the arbor, so what would drive the motion works? Or does a slip fit mean a tight fit such that the cannon pinon rotates with the arbor?

 

[glenhead]

By definition "slip fit" means that the pieces join together with no slop and with as little friction as practical. You want the clearance to be about .002" (.05mm) for a 0.25" (6mm) pin joint. With a blind hole a "perfect" slip fit of a cylindrical joint will be one of those where you get that glorious "pop" when you pull the pin out. I don't know the specifics of his build - is there some other doodad that provides the friction necessary to drive the hands, like a domed washer or something? If not then it seems likely that at some point you'll put a dimple in the cannon pinion to provide the friction. Or something,

Hope this helps.

Glen

 

[bytes2doc]

By definition "slip fit" means that the pieces join together with no slop and with as little friction as practical. You want the clearance to be about .002" (.05mm) for a 0.25" (6mm) pin joint. With a blind hole a "perfect" slip fit of a cylindrical joint will be one of those where you get that glorious "pop" when you pull the pin out. I don't know the specifics of his build - is there some other doodad that provides the friction necessary to drive the hands, like a domed washer or something? If not then it seems likely that at some point you'll put a dimple in the cannon pinion to provide the friction. Or something,

Hope this helps.

Glen

Thanks for the reply Glen. That is what I was thinking and so thought a press-fit would be better. There is a domed washer in the build as I recall, but will check it as I’m heading to the shop now.

thanks again.