Interference fit WRONG!
It is a fit always ensuring some interference between the hole and shaft in the coupling. The upper limit size of the hole is smaller or at least equal to the lower limit size of the shaft. RIGHT
This refers to parallel surfaces where the hole is actually smaller
than what you are fitting into it, NOT a taper fit...
...a good example of an 'interference fit' is a steel bearing in an alloy crankcase where you heat the crankcase, freeze the bearing and fit the one t'other; or a steel liner in an alloy cyclinder, NOT something that requires A BOLT to hold it in place...
Don't know if it helps really what it's called....but something above doesn't sound right to me:
- why is an interference fit limited to parallel surfaces? Is it common knowledge or a defined rule that it excludes tapers? Not being cocky, just curious.
- when I visualise the whole thing, the hole in the crank is
smaller than the shaft / axle / spindle; the hole
and shaft / axle / spindle both have a 2 degree taper that's all. If it wasn't
smaller, then the crank would run all the way past the taper and be closer to the BB cups.....
- in your example using heat / freezing to give some sort of assistance prior to assembly exploiting the different heat expansion rates of different metals, surely that is what the bolt is more-or-less doing instead by force rather than heat? I guess you could do the same, heat the crank up, put the axle in the freezer, then welly it all together with a big lump hammer, then put the bolt on. When everything settles at room temperature the crank hole would be slightly stretched and the bolt will simply stop it falling off and hence then have a torque value....or?
Anyhow...just grease them
Favorite quote on Retrobike:
Not worth the petrol to take it to the tip so it's down to the angle grinder to make it small enough to put in the wheely bin.