Spraying a Radiator

maddness · 11 Nov 2009 at 00:05

Hi, i was wondering if its safe to spray a 120.3 rad white using one of those radiator sprays (home central heating radiators white spray) - plasti-kote

would there be any drawbacks? would the rad be less efficient etc..

thanks

setter · 11 Nov 2009 at 00:11

Ive seen a few people spray rads on their builds in the case section of the forum, if you mask off the fin area and just paint the outer casing it should be fine.

maddness · 11 Nov 2009 at 00:15

i was looking to spray the fins too white, basically the whole lot, i figured this spray is for radiators and must have very good heat conductive properties? no?

Zenduri · 11 Nov 2009 at 00:16

Agree with setter, any paint on the fin area will act as an insulator and at a guess increase your temps by 2-5 at worst so just do the outside housing

setter · 11 Nov 2009 at 00:29

Have a look here madness.

http://forums.overclockers.co.uk/showpost.php?p=14076276&postcount=171

Should give you an idea of how to get it sprayed.

maddness · 11 Nov 2009 at 00:38

cheers, remember seeing that before, infact i posted a few posts down

will probably just do it as webbo has, the rad fins are blue so its almost purple lol

thanks

shadowscotland · 11 Nov 2009 at 12:11

maddness said:
i was looking to spray the fins too white, basically the whole lot, i figured this spray is for radiators and must have very good heat conductive properties? no?

Yes it doesn't have good 'Radient' heat properties AND have good thermal movement. But domestic rad's like watercooling rad are convective so colour makes very little differance.

A rad heating cycle will crack 'old style' gloss paint - and emulsion doesn't stick to metal very well so rad paints are usually acrylic or enamel (many new paints that call them selves gloss are not - they just give the 'gloss' finish - so can be used on domestic rads)

Radient heat is all about infrared radation so something that look white in the viable light spectrum may be 'black' (high emmissivity) in the infrared. (appoligies if I've got my psysics muddled

Linky
white emulsion has a emmissivity of .77 (measured value - linky)
'flat white' oil paint .91
Black is .92
Gray-green is .95
lamp black is .96
Krylon bbq paint is .97 (£7 a spray can)
3M Black Velvet 9560 is .99+
Polished copper .03
black oxidiized copper .78
True black body is 1 (perfect score)

Note forced air and convective heat loss used different values