Aluminum Gunnels in salt water

I appreciate all the info I got on canoeing in salt water. I am ready to go out and try some paddling in my Argosy, but I still have one concern. My canoe has aluminum gunnels, aluminum footbrace, and I believe aluminum rivets. I am not sure if the rivets are all aluminum or some combination of aluminum and a softer metal.



Will salt-water do some harm to the aluminum despite a routine wash after use in salt water? I am particularly concerned about salt water getting trapped in the rivets or gunnels despite a routine wash.



Do I need to do something special in the washing like using a powerwasher or washing with some kind of added surfactant to insure penetration into rivets and other fasenteners?



Probably not a big issue, but I have seen a lot of pitting and corrosion on aluminum parts on fishing reels and boating equipment down here on the gulf coast.



Mark

I guess you could go over the pop
rivets and seal them with something like SeamGrip or Aquaseal. I would not try to seal the gunnel flanges, because saltwater is going to sneak under there anyway. Better to use a thorough freshwater rinsing.

Not much damage

– Last Updated: Jan-19-09 7:22 PM EST –

There is alot of white pitting on our fleet of Grummans but they have been serving the guests at our AMC cottage since 1976.

I note that some of the floatatin is degraded though and wonder if saltwater (were on the ocean) has hastened its demise.

Grummans have open seams to the floatation and I wonder if rinsing would help or just waterlog the floatation.

I know the guests never rinsed the boats.


Brass however will corrode.

I havent seen any corrosion on the Wenonah that we occasionally use on the ocean. We rinse every use. We have had that boat for over fifteen years. It has aluminum gunwales.

salt
I can’t answer for canoes, but most of the trucks that haul our road salt to us are aluminum and I believe for the most part they just rinse them thoroughly.

beware sealing salt in
Be careful when sealing rivits, seams, gunwals etc as suggested. It probably won’t keep salt water out long term but will keep it in once it is there and make it very difficult to rinse out.

A good rinse
after every use and you will be fine. You do need to do more than just hose it down, though. Use a soft sponge or rag to wipe down the entire boat while rinsing, paying specila attention to the ungerside of the gunwales.

And if you can;t rinse right away, as long as you do not let the boat sit for extended periods with the salt encrustation it will be fine.

You can get rapid damage to aluminum in salt water thtough something called galvanic corrosion, but that only happens in the presense of two dissimilar metals and will not be a problem for your boat.

Re: Floatation
Any styrofoam that old is bound to be degrading a bit. I think ozone would be more detrimental than saltwater. A bigger threat to expanded polystyrene is that it soaks up water in teh voids formed when the beads are heated to expand them. It can become waterlogged, but I assume the canoes were stored hull-up.



Jim

Boshield
Paddlers of aluminum framed folding kayaks use Boshield T-9 to keep protect from salt-water corrosion. Just in the moving parts, mind you.



I have such a boat, as well as a canoe with aluminum gunwales and footbrace. In the canoe, I apply Boshield to the cotter pin that fixes the brace to the support. I don’t see any need to take such precautions with the gunwale rivets: they get drilled out anyway if replaced, don’t they?

Thanks everyone.
I’ll make sure I do a really thorough wash and wipe as much surface as I can while running water. Boshield completely slipped my mind. I will put that on the moving parts of the footbrace and on the adjustable seat parts.



Mark