Clear coating polished aluminum?

[Soxman]

I am in the process of a frame up restoration of a 1983 G1 and just finished polishing up the aluminum transmission gearbox and the steering gearbox to a bright shine and want to know if anybody has ever used a clear coat to keep the shine and if they had any success doing that.
Thanks in advance for any input

[Revolution]

Aluminum is a tricky but awesome metal. Its known for its corrosion resistance but its only corrosion resistant because its outer most surface oxidizes so fast and hard that the corrosion can't penetrate the oxide layer.

Thats what makes it tricky to keep a bright luster on it. I prefer aluminum in a polished but oxidized state, meaning all the pits, machining marks, and scratches are gone, but allowed to do its thing and oxidize. You can make a mirror finish on it but its not the natural state for aluminum to be in. I have learned to like the way it looks after being brought to a high polish-luster and allowed to dull slightly with oxidization.

Anything you do to try to stop the dulling of the aluminum is temporary at best, especially if it gets hot.

Anodizing is the most flattering thing that can be done long term for aluminum, it can be done at home, theres tons of great videos of home anodizing. It is a permeant surface finish. Now days you can pick almost any color you want for the dying part of anodizing, black, silver, red, blue, purple, yellow, green and brown.

For metals like gold, platinum, palladium, rhodium, nickel, chrome and stainless steel a high luster surface will last a lifetime if left alone. Aluminum is NOT one of those metals.

[Revolution]

I forgot to add, aluminum has a high thermal expansion rate, meaning as it heats up it grows a lot really fast compared to other metals. A clear coat will not match the expansion and contraction rate and will separate quickly from the surface of the aluminum.

[Mike Mac]

I did mine 3 yrs ago!! Polish only!!

Still looks the same today!!

[Revolution]

Originally Posted by Mike Mac

I did mine 3 yrs ago!! Polish only!!

Still looks the same today!!

Thats that slightly oxidized shine I am talking about.

[Revolution]

and I like it!

[meangreenmachine72]

I have taken a lot of pieces that are from the 70's and made them look great. I soak them in a delimer/ de-scaler for 10 minutes to remove and tough oxidation then polish them by hand with blue cleaner and the results are awesome.

[cgtech]

Originally Posted by Revolution

Aluminum is a tricky but awesome metal. Its known for its corrosion resistance but its only corrosion resistant because its outer most surface oxidizes so fast and hard that the corrosion can't penetrate the oxide layer.

Thats what makes it tricky to keep a bright luster on it. I prefer aluminum in a polished but oxidized state, meaning all the pits, machining marks, and scratches are gone, but allowed to do its thing and oxidize. You can make a mirror finish on it but its not the natural state for aluminum to be in. I have learned to like the way it looks after being brought to a high polish-luster and allowed to dull slightly with oxidization.

Anything you do to try to stop the dulling of the aluminum is temporary at best, especially if it gets hot.

Anodizing is the most flattering thing that can be done long term for aluminum, it can be done at home, theres tons of great videos of home anodizing. It is a permeant surface finish. Now days you can pick almost any color you want for the dying part of anodizing, black, silver, red, blue, purple, yellow, green and brown.

For metals like gold, platinum, palladium, rhodium, nickel, chrome and stainless steel a high luster surface will last a lifetime if left alone. Aluminum is NOT one of those metals.

An awesome, and accurate assessment of the great metal that was once worth more than gold. Aluminum, its a great, finicky metal. Love it!

[rib33024]

Tried all kinds of clear on chrome and aluminum, It always come out dull. Looks alot better if you just polish it, and no clear

[Mike Mac]

I Didn't take mine all the way, (just kind of a quicky), there is a finer compound that I could have used, but I ran out years ago, and didn't go get any. So... I got what I got, but it still looks like that now!!

Polished the valve cover and starter covers as well, again, kind of a quicky, but spent more time on the valve cover!!