I would suggest using what the gunsmiths use on aluminum. I can ck on the chemical content and if it is shippable. Would be happy to have it sent to U if it can be mailed. 73 Tim O'Rourke W4YN at ARRL.Net Low Power Amateur Radio Rocks Member of Flying Pigs,ARCI,GQRP,RSGB,ARRL Life Member NHRA Life Member