In <199708212149.QAA25077@nutria>, Todd Mullins wrote:
>Lawrence J Alexander writes:
>> [ ... ] but there is a reason for leaving the spacer in place and
>> using shims to set the bearing pre-load......When the castellated nut is
>> tightened against, in order, the outer bearing's inner race, the shims,
>> the spacer, the inner bearing's inner race and, finally, the seal
>> support, you effectively secure the outer end of the stub axle back
>> against the inner end and provide a much larger diameter axle for the hub
>> to rotate on. This added strength can be very important if you drive the
>> car hard!
>
>This is an interesting and unique observation. It makes a lot of sense
>and tickles all the right fuzzy areas of my addled brain. However, I'm
>still bugged by the fact that the spacers seem to be made of an
>incredibly soft, almost crumbly, metal that doesn't seem very strong.
It is a pretty sleazy metal, but it is a steel alloy and not pot
metal, at least. The reason it doesn't have to be strong is because
it is subjected only to compressive forces (under normal
circumstances). Rocks are pretty crumbly, but they hold up all kinds
of stuff.
>
>Also, I must ask: If this is a technically superior system, why didn't
>all car manufacturers use it?
Cost. Not just for the bits, but also for the fiddling during
manufacture. Most 'Murrican Arn uses tapered bearings but omits the
spacer and shims, and uses far less torque on the nut. In some cases,
more than finger tight can eat the bearings. I personally don't like
that much reliance on a split pin.
A. B. "a front wheel did fall off my '56 Olds" Bonds
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