> I too wondered what a "hardened" roll pin was. I thought perhaps
> that might have referred to a steel dowel, rather than a roll pin. The
> dowel, being solid, would of course be much stronger.
Roll pins come in a variety of types and materials, spring steel is
typically typically softer and easier to deform than other steels. Regular
carbon steel roll pins are the other alternative, and these are harder than
spring steel pins. If you want it to look pretty in 10 years, you can get
zinc plated and stainless roll pins as well. Needless to say, carbon steel
roll pins are what I was refering to.
The idea behind the roll pin, and the same with the bolt idea, is not to
relieve the taper pin of its load, but to compliment the taper pin. Since
the roll pin is supported on both ends by the fork body, it is practically
impossible to snap, it would have to snap twice before it became
ineffective. And unlike, a bolt, the roll pin has no threads, so the roll
pin provides a greater bearing surface for the shaft and fork body to
contact than the bolt does.
Bolts are clamping devices, they are not locating devices, and the fact that
they are often used as such, is a poor practice. The best solution, but one
needing considerably more work, is to insert a solid dowel with a very tight
interference fit into the second hole, then secure the dowel with a set
screw (loctite also recommended).
Kai
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