Bertram31.com General Bulletin Board

Re: ?? continuded

Posted By: Capt Patrick McCrary
Date: Saturday, 19 March 2005, at 9:04 p.m.

In Response To: Re: ?? continuded (cwj)

Charlie,

Sand the entire surface to a 180 grit finish.

You need to both acid wash with a 10% - 20% phosphoric acid/water solution & then treat with alodine solution.

Work 3 - 4 foot sections at a time, overlapping sections as you go through each chemical prep. Do all of the phosphoric first, rinse each section after keeping it wet for about 3 - 5 minutes with the acid. Then do the same thing with the alodine. You can use the clear or the yellow alodine since you're painting.

Allow the aluminium to dry thoroughly, wipe it down with denatured alcohol, and zinc chromate wash it with three coats. Zinc chromate paint is getting hard to find, but it's still around. Thin the zinc chromate to about the consistency of whole milk with the appropriate thinner recommended by the manufacturer, (usually acetone or lacquer thinner will work, but not always).

By making it that thin it will both flash dry faster and get down into the tooth of the sanded surface better.

Use a medium 3M refinishing pad to scuff up the dry zinc chromate, wipe down again with denatured alcohol and prime with any good anti-corrosive metal primer. A one part system is fine...

Since any painted aluminum is going to be an ongoing maintenance item, I'd just use a good one part polyurethane paint such as Interlux Brightside. Easy to apply, looks good, easy to spot repair later when the blisters start reappearing...

Best regards,

Patrick

Messages In This Thread

?? capt pat
cwj -- Saturday, 19 March 2005, at 4:08 p.m.

Re: ?? continuded
cwj -- Saturday, 19 March 2005, at 5:06 p.m.

Re: ?? continuded
Capt Patrick McCrary -- Saturday, 19 March 2005, at 9:04 p.m.

Re: ?? continuded
cwj -- Saturday, 19 March 2005, at 9:11 p.m.

Re: ?? continuded
bob lico -- Sunday, 20 March 2005, at 2:30 p.m.

Re: ?? continuded
John F. -- Sunday, 20 March 2005, at 6:47 a.m.

Re: ?? continuded
cwj -- Sunday, 20 March 2005, at 7:05 a.m.

Re: ?? continuded
Tom Annulli -- Sunday, 20 March 2005, at 12:48 p.m.

Re: ?? continuded
Harv -- Sunday, 20 March 2005, at 1:57 p.m.

Re: ?? continuded
Vic Roy -- Sunday, 20 March 2005, at 3:39 p.m.