Date:         Fri, 22 Dec 1995 14:46:43 -0800 (PST)
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         brandys@ichips.intel.com
Subject:      Re: Re[2]: Heater Box

ok, i have a rust paint question.

i have some rust spots, i want to treat them now so they don't get any
worse, and take care of it for good this summer when the sun comes
back out (i have no garage to work in:(

so i:
1) get all loose rust off
2) sand the spot down pretty well
3) here's my question...


i have a two part treatment, ones a primer and ones a stop/rust
thing  (not very technical i know).  they are both spray paint type
cans.  what happens to the existing, non rusted paint that gets one or
both of these on that area?  will it make the paint chip/crack and
fall away, or will it seal it also, until i can get to it?


>boxes warmer, I don't know. (perhaps someone who understands the physics
>involved can explain to me why color matters for heat conductivity--is 
>that the word?--, even in dark places.)



conduction is heat transfered via molecular collisions.  a spoon held
over a flame, the flame heats up the part of the spoon it is in
contact with, those molecules speed up, collide with its neighbors
till the whole spoon is nice and hot.  color has nothing to do with
conduction.

heat transfered by radiation (the sun radiates heat to the earth,
engine parts get hot and radiate heat to other parts. )  the color of
an object helps to determine how much heat it will absorb from the
hotter objects around it.  a dark color will absorb more heat (thus
becoming hotter) while a lighter colored object will reflect more of
the heat (absorbing less, stays cooler)  think of the difference
between wearing a black tshirt versus a white tshirt on a hot, bright
summer day.

DISCLAIMER:  there are MANY factors that determine how objects can
heat up, color is only one of them:)


forgive me, i modeled heat transfer equations for awhile.


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