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Gregg Alexander (Boglords)
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Username: Boglords

Post Number: 7
Registered: 1-2006
Posted From: 72.160.48.127

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Posted on Tuesday, August 21, 2007 - 2:38 am:   

I am getting ready to repaint and polish my '62 4106. When I stripped the paint I noticed some corrosion that has eaten through the aluminum above the main electrics panel behind the rear passenger wheel. I have considered tig welding but am afraid of weld through catching my finished interior on fire. Any insights?
Nick Badame Refrigeration Co. (Dnick85)
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Username: Dnick85

Post Number: 173
Registered: 2-2006
Posted From: 70.211.165.126

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Posted on Tuesday, August 21, 2007 - 7:06 am:   

Hi Greg,

One way would be to coat the aluminum with self etching primer, then use a body filler and sand smooth before repaint. The bodyfiller won't hold on the alum. without primer first.
Another way would be to replace the panel.

Good Luck
Nick-
marvin pack (Gomer)
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Username: Gomer

Post Number: 79
Registered: 3-2007
Posted From: 76.4.151.123

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Posted on Tuesday, August 21, 2007 - 4:25 pm:   

greg I had good results with sand blasting some spots on my coaches that i have built n the past and after that put white vinager onit and let it dry, then wipe it down with lacquer thinner and use etching primer then, use fiberglass that i use on caps,boats, etc let dry,sand,prime,sand,;PAINT yeah
gomer
Christopher Goodwin (Cgoodwin)
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Username: Cgoodwin

Post Number: 129
Registered: 10-2005
Posted From: 71.212.85.123

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Posted on Thursday, August 23, 2007 - 12:17 am:   

I TIG aluminum all day and I can tell you this, aluminum oxide melts at 3 times the temperature of aluminum and the only thing harder is diamond. If the aluminum has suffered an electrolytic reaction causing it to oxidize, do not try to weld it, the result will be like trying to fuse two cubes of butter with a blow torch, get it hot enough to shine and it will fall away.

To prep oxidized aluminum for welding I treat it with a strong alkaline solution, then water, then nitric acid. Wash it with water and dry.

Do not try to cover up the mess with fiberglass or resins, it will simply continue under the glass. What you need to do it cut it away and what you can not cut clean with a wire wheel or chemically, etch the aluminum with something like Metal-ready, then paint it with a restoration sealant like POR-15. Have a look at http://www.por15.com/

I don't own the company or work for them but I have been restoring German cars and classic bikes since I was 15 and this product is on my shelf, I paint my boat trailer with it, my dive gear, my Porsche, all my classic bikes, etc.

Once the damage has been contained, pop rivet an aluminum patch in place (with aluminum pop rivets - avoid dissimilar metals in contact with one another, if they must contact make sure both metals are coated with something where they meet and that no water can enter the union), pain it with POR-15 and spray the wheel well side of it with a good rubberized undercoat to prevent any more water from being sprayed onto the metal.

Do it right the first time and you won't be hiding a cancer which will return with more damage.
Gus Causbie (Gusc)
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Username: Gusc

Post Number: 462
Registered: 11-2005
Posted From: 63.97.117.27

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Posted on Thursday, August 23, 2007 - 4:53 pm:   

Chris,

Very good info which I will add to my library.

However, I really hesitate to use undercoat on anything since it tends to trap even the slightest bit of moisture and allow corrosion to start all over again. I stopped using it many years ago.

I prefer to use a good epoxy paint and maybe a stick on insulation pad. I've had much better luck with this method.

On the patch, I would rivet it to the inside of the hole if possible and fill before painting. If he isn't painting I would put it outside.

(Message edited by gusc on August 23, 2007)
john w. roan (Chessie4905)
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Username: Chessie4905

Post Number: 725
Registered: 10-2003
Posted From: 71.58.117.21

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Posted on Thursday, August 23, 2007 - 8:48 pm:   

Just a thought, but how about using plastic aluminum. Don't know if it might work well. I think Fast Fred said something a while back about a salt neutralizer used in the boating world.
Christopher Goodwin (Cgoodwin)
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Username: Cgoodwin

Post Number: 130
Registered: 10-2005
Posted From: 71.212.51.127

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Posted on Saturday, August 25, 2007 - 1:29 am:   

A quality undercoating or waxoil (not sure if it is available this side of the pond) should seal out any moisture. It is dissimilar metals which really need to be avoided and capping (covering the mess) which is akin to sweeping things under the carpet.

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