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PCProffitt
 
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Default Pinewood Derby - Part Deux -Bring It On Sylvan.

Xylem wrote:
This year the wheels will be trued on the lathe and the hub coned to
relieve the friction between hub and body. This year the internal
part of the hub will be polished to an ungodly sheen.

This year will not suck.

This year the wheels will be packed with the appropriate lubricant,
rather than a spit of WD-40.

This will stop some of the sucking.


Here's my humble tip on preparation and lubrication of tuned wheels on
tuned axles (all from approved stock as required).

Before you polish the internal part of the hub, thread it with a tap
that is just large enough to leave grooves in the inside of the hub
(probably 8-32 or 10-32, but I don't remember). Then polish the inside.
Then put the wheel on the polished axle and use large amounts of
powdered graphite as a lubricant to fill the internal grooves. Besides
reducing friction by reducing the internal surface area, the grooves
left by the tap seem to 'capture' some of the graphite which provides
longer and better lubrication since you cannot perform any maintenance
after the race begins.

The year we discovered this little trick we came in first in our pack
and seventh in the district.