corrosion mast bottom

[taoist]

When I bought my Bristol 31 this past year the surveyor indicated that there was some corrosion at the mast base. Right now the mast is out but will be re-stepped soon. Obviously a good time to address this issue. Any ideas to prevent further corrosion?

[tkeithlu]

Sand down to good aluminum, leave the surface rough for adhesion, prime and paint. Stop whatever leak left water against your mast. Move on to the next problem.

[Lodesman]

The only guaranteed way to stop corrosion, is to not use it in a corrosive environment (ie. the sea). Barring that, you can get some corrosion-resistance from chemical clean and alodine prep:

https://www.aircraftspruce.com/pages.../alumiprep.php

https://www.aircraftspruce.com/catal...lodine1001.php

Then a 2-part paint would probably be best, but I have no expertise there.

[psk125]

Before you paint, how bad is the corrosion? We saw an aluminum can on the beach today that was essentially a bunch of holes that the waves had twisted into a pretzel. If there is enough solid material, sanding it down & painting is the way to go. If it's too far gone you may need a sleeve. A photo could help us provide the right advice, but your surveyor might be the best source for a knowledgeable solution.

[coopec43]

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[taoist]

Many thanks to one and all for the feedback. Unfortunately, we had a death in the family and I had to leave town and by the time I got back they had re-stepped the mast. However, this info will serve me well the next time I have the mast pulled.