g8 fasteners

[Jeff Taylor <jbtaylor@domain.elided>]

Terry,

If this was a G8 bolt that was purchased at the local hardware store, I would
be very suspicious that it is actually a grade 8 bolt. Counterfeit hardware is
a huge problem for industry. Even if it was installed from at the factory, it
could well have been counterfeit. 

I have never trusted hardware store fasteners and try to avoid them. I get
most of my hardware from industrial supply houses, either locally, or from
McMaster-Carr. 

Also, if that bolt was installed from the factory that way, it is not
surprising that it failed. It sounds like it was loaded in single shear, a
situation for which that type of fastener was never designed. Better options
would be to distribute the load across the faster in a double shear
application, or to have a hardened pin custom made to fit _tightly_ in the
holes. What about using a larger rod end bearing and moving up to 3/8" hardware

Jeff Taylor 


Terry Rust wrote:
> 
> yesterday the bolt sheared off at the pedal interface. It sheared cleanly
> with no evidence of deformation or thread damage. I need to replace the
> bolt obviously and picked up some grade 5 and grade 8 to put in there, the
> one that sheared was a grade 8. So my question is, is this an application
> where a softer bolt (grade5) works better than a harder (gr 8) one, or do I
> 
> TIA
>