Re: Do how I clean Aluminum hull?
I suspect your boat is corroded.<br /><br />Aluminum is a very active metal and must be protected from electrolisis, especially in salt water. I was once given an aluminum boat that had a lot of time in salt water. The prior owner said it was impossible to protect the boat from electrolisis without an active system. The result was that the boat corroded. And in some places the corrosion went through the hull to create holes!<br /><br />Signposts of corrosion are a white powdery residue with a rough surface under the residue. If that is what you have, the only solution is to sand the surface fair then with finer and finer grits of wet and dry get to an almost polished surface. Then use buffing compounds and buffing wheels on an offset grinder to get it to shine. The shine can be as good as this
http://www.sculpturegallery.com/sculpture/piggy_bank.html How far do you want to go? <br /><br />Unfortunately, it will be really difficult to get an even shine if the boat is rivited together and the shine will not last because the oxygen in the air will react with the aluminum and cover the surface with aluminum oxide (the equivalent of aluminum rust) which will dull the finish. You could constantly polish the boat to keep it shiny (as in motorcycle crank cases), but that is not practical for a boat.<br /><br />Probably a better solution is to paint the boat. Aluminum can be painted and the paint can stick to the aluminum if proper techniques and materials are used. If not, the paint will fall off. You must clean and fair the auminum, then etch it with an acid, then clean it and maybe neutralize the acid, then prime it, then sand it, then paint it with something like Imron all with proper breathing protection. Also, remember that even with a hull coating like Imron you must protect the hull from electrolisis!<br /><br />You see beautifully painted aluminum all the time on airplanes. Check some airplane maintenence sites for the proper procedures and materials to paint aluminum. You might also check the Interlux and Petit sites for instructions and materials.<br /><br />Good luck with it.