powder coating vs anodising on aluminium

[TrevS]

Hi all

I was talking to a fabricator about the aluminium panels on my car today. He mentioned that he was having some panels anodised in gold as it gives a really nice finish and improves the strength of the panels.

I have been planning on having my panels powder coated in satin black to match my chassis but wondered if having the panels anodised in black might be a better solution. Has anyone got any experience on this subject and can give me some advice?

Thanks all

Trevor

 

[Phil]

Trev:
Anodizing is basically a coating similar to a dye which is applied after a mild acid etch of the aluminum, and although it looks nice it scratches easily.
Also anodizing is limited to a smooth finish unless you go for hardcoat which is much more durable and was originally developed for military ordinance and high wear items.
Check with Bill Cooke on this as he hardcoated his uprights with this material.

Powdercoat is a really durable finish, and comes in textures and finishes that are too numerous to mention.
The real durability IMHO is in powdercoat. You would need to go to a reputable person as the substrate must be super clean and free of oxidation or you may get blistering or peeling.
Colors are almost unlimited, and some of the colors are available with a speckled look, basically whatever you desire.

Whichever way you decide, get a reputable shop to do the work.
Good Luck
Phil

 

[Mark]

I do powdercoating on the side, and have been doing some experimenting with anodizing lately. I generally tell people, if powdercoat is too thick go ano...otherwise enjoy the durability, and color/finish options of powder.

 

[Brett James-McCall]

Trevor,
I would hard anodise if I was going to do it. Powder coating will also scratch, just look at a lot of alloy wheels for instance.

I've just gone for painting using a black stone chip paint.

 

[RichardH]

My understanding on this is that Anodising will, to a small degree chemically harden the surface as well as giving a protective finish.
Although I personally like the surface of powder coating, which with a thicker layer will give slightly more resistance with chipping, I have also heard stories of major component corrosion underneath powder coating, because if it does chip, then corrosion can travel underneath the surface with little or no visible effect.

 

[TrevS]

hmm so interesting responses here, seems there is no preferred route. Having done a bit more reading I know I want the panels to have a matt rather than shiny finish and durability is the top priority so powder coating looks to be the best bet even though anodising is supposed to harden the material slightly.

That said I can see a need for anodising on my build. I think it would be a great way to make smaller components and detail work really stand out and give it a really strong finish.

This picture shows an example of a powder coated panel next to an anodised component to give you an idea of what I mean.

http://i817.photobucket.com/albums/zz96/canonsony/IMG_4078.jpg

Trev

 

[Mike Pass]

If you powdercoat the panels before you fix them on using Sikaflex and rivets you may find that the Sikaflex does not adhere well to the powdercoat which being plastic has a teflon like quality. Maybe leaving the powdercoat away from the areas of actual contact would give a better bond.
Cheers
Mike

 

[cal]

we mfg components for helicopters, never use powder coat on aluminum, we only use type III hard anodize. very hard to scratch.

MIL-A-8625(latest version), Type III, Class 2 black, 2.0 mil coating thickness

 

[TrevS]

Ok, I am now coming back round to the idea of anodising the panels. If it means the sealant will take better to the panel and I can get a hard wearing finish then it makes more sense as it will also help harden the panels.

Do you know if you can get anodising in matt black colour or does the dye take on the reflective properties of the aluminium?

Thanks

Trev

 

[Frank Catt]

Trev, you had better get a fixed quote on hard anodising before you jump, it can be a very expensive process unless you know somebody _____ ! Also, make sure every fixing and utility hole is cut and drilled, and all bends are perfectly shaped, before you have the process done. I dont use hard anodising on side panels for various reasons, including the above, I do a different way. Frank

 

[cal]

frank is very correct. we go to the extreme. best to take your parts to a good ano shop, explain what your doing, they will advise the best and most cost effective procedure. also color options etc.

 

[TrevS]

Contacted a few companies about the possibility of getting the panels anodised so we'll wait and see what they advise and of course the costs involved. I've got no problems getting the panels powder coated if that's the easier option but obviously want my panels to look as good as possible and be as durable as they can be.

Out of interest does anyone have any images of their panels anodised that they can post up?

Thanks

Trev

 

[Mike Pass]

Why not etch prime and then normal two pack? Seems to work OK on most car bodies!
Cheers
Mike