Painting heatsinks

[davesaudio]

is aluminum oxide stable?
I gather it is soft unless done by an anodizing process
it should be easy to oxidise aluminum-but how would it be if lacquer or clear coating applied over the soft oxide?

proper anodizing sounds like a pain and the alodine compounds rare and nasty too

 

[Dark Shadow]

So if you did some test at Bombardier you should heard about NMF Canada. That where i'm working. 6 years experience on aerospace surface finish. Alodize, Chemical Film, Gold plating, nickel plating, copper plating.

Did you know that Chemical film exist also for Copper and is used alot in microwave telecommunication system to protect the copper from corroding?

Francois Gregoire

 

[Dark Shadow]

Anodise is not very complicated....you just need the right chemical and hardware...The biggest problem is to have a safe place to install the equipment...

I would not suggest you to paint over natual oxidation of the aluminium...the paint adhasion is very poor on this kind of surface...try to find a place that can do the alodine process for you, or if you live near montreal i'm able to have access to the chemical and do it. =)

Francois Gregoire

 

[ashok]

Alodine.

This sounds like an interesting way to treat Aluminum. Unfortunately we do not get it here nor can we get it in small quantities ( all kinds of restrictions and rules).
So what does alodine contain. Can we make it up from its component parts ?
Thanks.

 

[Dark Shadow]

I'm pretty sure that it possible....

I know for a fact that the major component is chromic Acid but I don't know the rest of the composition.

I will check monday with the chemist at work...in fact he have a doctorat in chemistry so if it possible He should know.

I will keep you inform if it is possible.

I know for a fact that the major component is chromic Acid but I don't know the rest of the composition.

Francois Gregoire

 

[Tim F]

Henrik
These heatsinks sound similar to some I purchased on e-bay a couple of weeks ago. How deep are the fins & are they ribbed.
I planned on getting mine black dyed & annodised as according to
everything I read the colour can have a significant effect in the heat dissipation process.
From my motorcycling days we used to use a paint called SPEREX VHT (very high temperature.) It came in aerosol cans & was intended for exhaust systems. It could be applied in relatively thin coats & if baked afterwards gave a pretty tough finnish.
I used it for engine casings with excellent results.
Similar paints are readily available in the U.K. from car accessory stores although I have'nt seen the SPEREX brand for some time.
This might be useful to you if the fins are not to deep say 40mm or so.