Bill Finch had a very nice experiment there, concerning crank rod
elongation.  I have also noticed that maple elongates less, but there
are different qualities of maple, too.

The self-lubrication of wood comes from its resins liquefying under
friction heat, and you will then notice a varnish buildup on the cranks
after awhile.  This is what gets hot in minuscule amounts.  The reason
oak has less friction but more elongation is probably obvious -- the
internal "wicking action" of the wood is stronger in oak because of the
"sinew-like structure of oak with the large pores, but the compression
of oak is greater because there is less wood contacting the crank,
since the pores are big and hollow.

However, the reason for the knocking of wooden rods is due to the
stopping and starting of these pumps, thousands of times a year.  Once
the rod cools off and the resin gets hard, then you get a tremendous
amount of wear and tear until the rods get hot again.  (I'm not talking
about the whole rod -- just a very thin contacting surface, so you
can't measure it very well.)

The grease must be there, or your orchestrion or band organ will
definitely start knocking again, and you will have to make new rods.
The grease substitutes for wood resins, so, since you are either going
to use wood resins or grease, you'd better pick a good grease.

A little common sense will tell you that any test run continuously can
only test the continuous operation factor.  Testing engines that way
produces absolutely wonderful results, too.  But turning them on and
off, letting them get cold, and then switching them back on, and you
get terrible results.  Even changing the speed, changing the loading
factor, etc. makes enormous differences in your results.  So when this
happens all the time in band organs, you end up instead looking around
for a truly great _grease._

Craig Brougher

 [ Interesting thought.  The old oilfield pumping engines in Long
 [ Beach CA ran continuously for years, never stopping except to change
 [ the motor oil.  And I remember when (before the modern lube-oil
 [ additives) the automobile owners manual always advised the driver
 [ to allow the engine to reach operating temperature before any
 [ strenuous driving.  -- Robbie