Posted By : Mark Stradling, 04-Dec-2003,
04:41pm
I was of the opinion special wheel nuts should be used for two reasons.
1) The wheel nut 'pinches' the aluminium wheel to the hub. The loads at each wheel nut will vary as the wheel rotates. Now, unlike steel aluminium
doesn't have a safe loading, but gets damaged by each and every compress/release cycle. This means eventually ANY aluminium wheel WILL fail. If one
wheel nut design concentrates this stress point more than another, it will fail sooner. The special nuts should maximise the life of your wheels.
(this is the same mechanisum that caused DeHaveland Comets to fall apart in mid flight if you are interested)
2) Your average wheel nut is mild steel. Your average aluminium wheel is.... umm, aluminium. As most of us who have had fun with the steel water
pipe that runs through the aluminium inlet manifold will know, these two don't mix well. Basically steel likes to steel electrons from aluminium,
at which point it's a powder and not a metal and not much use for anything. I would imagin 'proper' ally wheel nuts are stainless steel, or some
other less re-active metal. (this is the same mechanisum that caused the engines to fall off Boing 747's in mid flight - where the steel bolt used
to hold the engine on was screwed directly through the aluminium engine mounting).
Ahh, all those materials lectures at Uni. DO have a use.... ^_^
