[Captain Bling]

I have a 46' 1968 aluminum hull Roamer with Imron paint. The upper rub rail is wood and the lower is aluminum faired into the hull. They both have ss screws which fasten the wood rail and the ss rub rail to the hull. It appears to me the source of the bubbling is external water getting in behind the paint via the screw holes.

I would assume this is a common issue, and would like to know if someone has had successfully eliminated the problem. I thought of possible solutions, but have not acted upon them until I know it will work.

1. Refinish the bubbled areas and fill in the screw holes permanently eliminating any point the water can get under the paint. I would then have to find some kind of chemical fastener (epoxy, 3M PSA tape) to hold the rub rails to the hull, which is questionable.

2. Refinish the bubbled areas and apply caulk or silicone into the screw holes and apply some sort of gasket or caulk bed under the rub rail before screwing it to the hull.

Any input is appreciated!

[m2m]

The only way to repair this problem is to remove the rubrails sandblast (or grind) all areas of corrosion apply a barrier coat and topcoat of paint reinstall the rubrails using both a bedding compound such as 3M 5200 along with a very thin rubber gasket. All screws should be coated with with 5200 as well. With aluminum the problem never permanently goes away, but if you prep the surface right you can keep the problem to a minumun.

[K1W1]

Originally Posted by m2m

The only way to repair this problem is to remove the rubrails sandblast (or grind) all areas of corrosion apply a barrier coat and topcoat of paint reinstall the rubrails using both a bedding compound such as 3M 5200 along with a very thin rubber gasket. All screws should be coated with with 5200 as well. With aluminum the problem never permanently goes away, but if you prep the surface right you can keep the problem to a minumun.

I would go very easy on using 5200 as a bedding compound as described above, you would never get the rails off without smashing them to pieces if you stick them on with this glue of glues. There are other products specifically designed for this that would be much better suited to this task.

[m2m]

I agree that 5200 is a scary thing to use if you want to get something off, perhaps Boatlife would have been a better choice of materials--do not use silicone as paint will not stick to it or any area where there is the slighest bit of residue.

[Captain Bling]

I agree about the 5200. Sometimes I wonder if it wouldn't be easier to just eliminate the SS & wood rub rails altogether......fill in the screw holes which are the real culprit, and take your chances with out the protection of the rails.

I think I would rather deal with an occasional scrape or scratch (which can be avoided) vs inevitable bubbling paint issues.

[m2m]

Removing the rubrails all togethor is one way to go but the only way to seal the holes up properly is to weld them and with welding you get into more head aches. fire being the main concern, old aluminum is very tough if not impossible to weld due to umpurities in the metal, and the least of your worries is you loose the protection that they were put there in the first place for. There is a company by the name of Smart Rails that uses a glue to install splash rails on boats that is quite impressive, but I am not sure if it works on aluminum, might be worth a phone call.

[Capt J]

I also wouldn't use 5200. Life seal from boatlife would be a good choice. If you use tefgel on the threads of the screws it should help. You could countersink the screws (at least in the wood rubrail) in the rubrail and then fair over them and then paint the rub rails. This should seal the screws and help.