[Top] [All Lists]

Re: RE: To paint, or NOT to paint

To: <>
Subject: Re: RE: To paint, or NOT to paint
From: "Tim Mullen" <>
Date: Mon, 25 Oct 1999 07:19:34 -0700
Scott Hall wrote (about painting calipers):
> I think if you're going to coat them at all, powdercoat them. 
> <...>
> white lets off more heat, but I doubt the color will make a 
> noticeable difference.  <...>

I would think that powdercoating them, although good from a durability point of 
might not be such a good idea from a heat transfer point of view.  The smooth 
powder coat finish would probably act as a good thermal barrier acting to keep 
heat in the caliper.

As for the color white letting off more heat, the opposite is true (if I 
remember my heat 
transfer from my distant college years).  White is a good a reflecting heat 
(i.e. a white 
car doesn't get as hot as a black car sitting in the sun), but black is a 
*much* better 
heat radiator (i.e. ever wonder why air cooled motorcycle cylinders/heads - the 
ones anyway - are black?  For that matter why do you think they paint 
radiators black?).  Dull unpainted surfaces will radiate heat better than 
painted surfaces 
(the paint usually acts as an insulator), flat (non-glossy) surfaces radiate 
better than 
smooth, polished, or glossy surfaces.  Black radiates (and absorbs) heat better 
white, or any other color for that matter.  With all the above, there are 
exceptions - 
there are special paint coatings that actually radiate better (talk to NASA), 
etc., but 
in general the above applies.

And as Scott said, it probably doesn't matter anyway...

Tim Mullen

<Prev in Thread] Current Thread [Next in Thread>