If the Flyer mast is 40 feet, a 50 degree change is 1/4 inch (I think!). Its roughly
linear for our purposes, so I'd guess that the black might cause an expansion equal to one
turn on the turnbuckle.

Since you have the mast down, why don't you measure it early in the morning, and then in
the afternoon sun. You can report back and be the envy of the group!

BTW, I never liked black masts - I think white would look nice.


"Dennis Vogel" wrote in message
ink.net...
Thanks Jeff, but the mast gets too hot to touch hanging horizontal waiting
to be painted. So it's a lot more than a few degrees.

Dennis

Oh Boy. Coefficients of Thermal Expansion!

The several degrees of extra heat captured by the black mast might come
out to something
like a fiftieth or twentieth of inch expansion on a long mast. A bigger
issue might be if
the mast is setup and tuned on a cold Spring day - the temp rise to a hot
Summer day could
be 50 degrees, which might result in an expansion of maybe a part in 2000,
which would be
around half an inch for a long mast. I think I'll ask my rigger if they
take this into
account.

(These number are all SWAGs - Scientific Wild Ass Guesses)


"Bobsprit" wrote in message
...

Dumb people. My friend's Santana 30/30 has a black mast. On hot days we
need to
use sails from a Rhodes 19 to get a proper fit. We usually have to
change the
stays as well because the mast can change more 3' in height.

RB