Elsie (L C)
1978 FJ40 build up. I've owned this FJ40 for 13 years and I have recently been able to afford to do fun things like the Aluminum tub and the 350 conversion that I've been planning for ... well... 13 years.
It's not my 1st FJ40. I had to put a tired 1980 w/power steering to sleep and I bought a 1976 parts truck when I lived in WY several years ago. I'm going to start this thread with the aluminum tub prep and add info as I have time to.
I think there are a lot of people out there that are afraid of aluminum because it's difficult to get a straight answer as to how to prep and paint it correctly. I know I was really conflicted about what option to choose, and fiberglass almost won because I wasn't sure how I would paint aluminum correctly. The last thing I wanted was a $3,500 ugly flakey box. I had a steel one. I almost resolved to just polishing the tub and leaving it bare, and that's an option, but it's a total pain. I had aluminum quarters that were bare, they were cool looking, but I spent more time polishing them and waxing them than I did installing them. Paint is definitely the way to go with aluminum, especially if you're going to drive it.
There are a lot of ways to paint Aluminum. I'm not saying this is the one-and-only way, but I did a lot of research and I found answers that have worked for me so I figured I'd share them here.
I happen to work for a company whose owner fancies old vintage warbirds. From the venerable F8 Bearcat to the P51 Mustang that is sitting in his hangar I knew these fellas knew how to paint aluminum. I decided to question the full-time A&P mechanic who almost wouldn't stop talking about it. This guy is a wealth of knowledge. After having painted the $750,000 Mustang 10 years ago and a recoat of the priceless F8F, Wayne knew what he was doing and imparted some wisdom to me, and I figured I'd pass that on. It's worked for me. I'm not saying this is the only way to do it, but this way will surely take the -what-if's- out of the 1st and most important steps in finishing your brand new tub.
Materials needed...
Aluminum tub. ******Aluminum* Replacement* Bodies* & *Accessories *for* Land* Cruisers,* Jeeps**&* Samurai's - Home
Bucket with water and a few drops of Dawn detergent
rubber gloves, safety goggles, and a light respirator or face mask, all-purpose spray bottle
Alumiprep 33. 1 qt. ALUMIPREP NO. 33 from Aircraft Spruce
Alodine 1201 1 gal. ALODINE 1201 from Aircraft Spruce
This will get you a great corrosion resistant prepared surface for any epoxy primer and paint...
Here's how it starts...
Wash the tub with the dawn detergent, just a little soap will get the grime off without leaving a residue. After washing it I decided to sand the outer panels with 80 grit closed paper on a random orbital sander. There were a few grinder marks left over from the manufacturing process. I washed it again just because that's how I am.
Acid Etching.
This is where you will need the gloves, goggles, and mask. this stuff is nasty, you will understand when you do it.
After washing the tub, mix one part of the Alumiprep 33 with 3 parts of water in an all purpose spray bottle and spray it on liberally to the aluminum. Leave it on there for no more than 5 minutes. This will etch the surface for a good adhesion and also draw any oils & dirt from the aluminum to the top where they can be rinsed off. After the 5 minutes just rinse the acid solution from the surface, let it dry thoroughly, and you're ready for the next step.
Conversion coating.
The idea behind a conversion coat is to create a chemical layer between the Aluminum and the air/water/whatever that is less reactive than the Aluminum itself. This reduces corrosion/oxidation. The Alodine 1201 is up to the task. We've seen chromate coating on bolts, this is essentially the same idea. It's not paint, but it IS something that DOES prevent corrosion. Just like a chromate coating on a bolt if it does get scratched off it is vulnerable to corrosion again.
Applying it is so easy you'll think you're doing it wrong. It's essentially... brush it or spray it on full strength and let it sit for 7-10 minutes, and rinse it off with water. Let it dry... poof, your tub is a funky yellowish color (just for effect) and molecularly protected from corrosives and ready for your favorite epoxy primer then your favorite paint, just like painting any other metal.
I painted my tub myself, but if I were to take it to a body shop I would do this process BEFORE I got it there. I'm not exactly sure all body shops are keen on painting bare aluminum. I'm sure that there are exceptions, but I would let a boat builder paint an aluminum tub before I'd let an automotive shop paint it. But that's just how I am.
It's really not as mysterious as you would think. I honestly thought I was doing it wrong because it was so easy. You may want to check with your local EPA or regulatory bodies before using or rinsing these chemicals away with your hose.
1978 FJ40 build up. I've owned this FJ40 for 13 years and I have recently been able to afford to do fun things like the Aluminum tub and the 350 conversion that I've been planning for ... well... 13 years.
It's not my 1st FJ40. I had to put a tired 1980 w/power steering to sleep and I bought a 1976 parts truck when I lived in WY several years ago. I'm going to start this thread with the aluminum tub prep and add info as I have time to.
I think there are a lot of people out there that are afraid of aluminum because it's difficult to get a straight answer as to how to prep and paint it correctly. I know I was really conflicted about what option to choose, and fiberglass almost won because I wasn't sure how I would paint aluminum correctly. The last thing I wanted was a $3,500 ugly flakey box. I had a steel one. I almost resolved to just polishing the tub and leaving it bare, and that's an option, but it's a total pain. I had aluminum quarters that were bare, they were cool looking, but I spent more time polishing them and waxing them than I did installing them. Paint is definitely the way to go with aluminum, especially if you're going to drive it.
There are a lot of ways to paint Aluminum. I'm not saying this is the one-and-only way, but I did a lot of research and I found answers that have worked for me so I figured I'd share them here.
I happen to work for a company whose owner fancies old vintage warbirds. From the venerable F8 Bearcat to the P51 Mustang that is sitting in his hangar I knew these fellas knew how to paint aluminum. I decided to question the full-time A&P mechanic who almost wouldn't stop talking about it. This guy is a wealth of knowledge. After having painted the $750,000 Mustang 10 years ago and a recoat of the priceless F8F, Wayne knew what he was doing and imparted some wisdom to me, and I figured I'd pass that on. It's worked for me. I'm not saying this is the only way to do it, but this way will surely take the -what-if's- out of the 1st and most important steps in finishing your brand new tub.
Materials needed...
Aluminum tub. ******Aluminum* Replacement* Bodies* & *Accessories *for* Land* Cruisers,* Jeeps**&* Samurai's - Home
Bucket with water and a few drops of Dawn detergent
rubber gloves, safety goggles, and a light respirator or face mask, all-purpose spray bottle
Alumiprep 33. 1 qt. ALUMIPREP NO. 33 from Aircraft Spruce
Alodine 1201 1 gal. ALODINE 1201 from Aircraft Spruce
This will get you a great corrosion resistant prepared surface for any epoxy primer and paint...
Here's how it starts...
Wash the tub with the dawn detergent, just a little soap will get the grime off without leaving a residue. After washing it I decided to sand the outer panels with 80 grit closed paper on a random orbital sander. There were a few grinder marks left over from the manufacturing process. I washed it again just because that's how I am.
Acid Etching.
This is where you will need the gloves, goggles, and mask. this stuff is nasty, you will understand when you do it.
After washing the tub, mix one part of the Alumiprep 33 with 3 parts of water in an all purpose spray bottle and spray it on liberally to the aluminum. Leave it on there for no more than 5 minutes. This will etch the surface for a good adhesion and also draw any oils & dirt from the aluminum to the top where they can be rinsed off. After the 5 minutes just rinse the acid solution from the surface, let it dry thoroughly, and you're ready for the next step.
Conversion coating.
The idea behind a conversion coat is to create a chemical layer between the Aluminum and the air/water/whatever that is less reactive than the Aluminum itself. This reduces corrosion/oxidation. The Alodine 1201 is up to the task. We've seen chromate coating on bolts, this is essentially the same idea. It's not paint, but it IS something that DOES prevent corrosion. Just like a chromate coating on a bolt if it does get scratched off it is vulnerable to corrosion again.
Applying it is so easy you'll think you're doing it wrong. It's essentially... brush it or spray it on full strength and let it sit for 7-10 minutes, and rinse it off with water. Let it dry... poof, your tub is a funky yellowish color (just for effect) and molecularly protected from corrosives and ready for your favorite epoxy primer then your favorite paint, just like painting any other metal.
I painted my tub myself, but if I were to take it to a body shop I would do this process BEFORE I got it there. I'm not exactly sure all body shops are keen on painting bare aluminum. I'm sure that there are exceptions, but I would let a boat builder paint an aluminum tub before I'd let an automotive shop paint it. But that's just how I am.
It's really not as mysterious as you would think. I honestly thought I was doing it wrong because it was so easy. You may want to check with your local EPA or regulatory bodies before using or rinsing these chemicals away with your hose.
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