Reason im asking is ive got hammerite direct to rust paint
http://www.ebay.co.uk/itm/HAMMERITE-SMO ... 231be8cb25
ive allready painted the front struts with it and control arms to tidy them up, colour was black though
am i cool to paint up the diff with it? and arms and subframe, with the exhaust system around that area as well?
or will it just burn off,
Does the rear end get hot? diff trailing arms etc
Moderator: martauto
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bss325i
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Dont paint the back plate of the diff as its cast alloy and has cooling fins. The back plate is used to cool the diff oil and black paint is a heat insulator.
The rest is fine but it may flake off the exhaust.
The rest is fine but it may flake off the exhaust.
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greg124
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Black paint is not a heat insulator.
We used to get matt black aluminium heatsinks because they dissipate more heat away than 'aluminium coloured' aluminium heatsinks.
Black things radiate better than shiny metal things, but matt black is best. Anodizing would be best, but if you must paint it a thin coat is best.
We used to get matt black aluminium heatsinks because they dissipate more heat away than 'aluminium coloured' aluminium heatsinks.
Black things radiate better than shiny metal things, but matt black is best. Anodizing would be best, but if you must paint it a thin coat is best.
Schadenfreude - the German's haven't got a word for that.
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Brianmoooore
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Black bodies radiate heat far more effectively than white or shiny bodies, but not necessarily if you add an insulating layer in the form of paint, which, in the case of Hammerite will be a VERY thick layer as paints go.
I'm not enthusiastic about the use of Hammerite on cars, as it tends to be far too brittle, chipping off with the slightest knock.
I'm not enthusiastic about the use of Hammerite on cars, as it tends to be far too brittle, chipping off with the slightest knock.
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bss325i
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The bottom line is, don't paint your diff back plate!
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bss325i
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And yes I should have worded my first post properly.
Paint acts as an insulator and Black does radiate heat hence black cars with black leather = fooking hot in summer!
Paint acts as an insulator and Black does radiate heat hence black cars with black leather = fooking hot in summer!

