I have tried just about every rattle can clear coat spray there is to try and seal up bare aluminum and keep it looking good, sofar all of them have turned yellow, sticky or flake off.
Power coat clear and anodizing are great but expensive and I hate to pay someone else to do my stuff.
I think I am getting close to a solution, these two products are what I'm testing at the moment,
http://www.por15.com/GLISTEN-PC_p_45.html
http://www.sharkhide.com/mpinfo.html
Both are very different but look very promising. I have made up some test pieces of cast aluminum, sheet aluminum and bare polished steel and over the next few months will throw a number of different environments and materials at these coatings to see how they hold up.
I'll start with the simple stuff and work my way up to oil, gasoline, battery acid and scratching.
The products were applied under ideal conditions with proper prep and I thought some here would be interested to see the results.
These coatings look so promising that I have also started applying them to my engine parts.
One of the members here, CARELESS was generous enough to give me an oz. of Sharkhide so I could do this comparison.
First impressions, Glisten like most POR15 coatings is pretty nasty on the lungs but thick, rock hard and very shiny, I have a feeling this coating is going sail through most of the tests.
It says it will not hold brushstokes but that was not the case when I applied it, I think it wouldn't have done it if it had been thinned a bit on the first coat or if it was sprayed.
Mix ONLY what you need, a little bit goes a long way, I made the mistake of mixing it all up and wasted 7/8th of the can.
Sharkhide is a very thin coating, leaves a semi gloss finish but if the piece you are coating is shiny it will let that show through and is extremely easy to use. It takes at least 3 coats to start to build.
With this coating you notice the piece itself, not the coating which is not the case with Glisten.
Sharkhide also goes a long way, it will be years before I use up the whole can.
Some pics,