I have an ally boom and the extension was totally seized on one side. I managed to give it a few adjustments with the knock-o-meter and some WD40 and that freed it up. Once it was free i sprayed a bit more WD40 on it and the white corrosion/build up disappeared.
I'll be using it more often because the lubricant displaces the water to prevent that from happening again. Regular maintenance will always be need but.

Thanks for that. Not 100% sure about WD40 - would that stuff eat away the foam in the core of the boom?

^^^great idea
Also try your local yacht shop. they have a good range of products ideal for this exact purpose

K Dog said...

Thanks for that. Not 100% sure about WD40 - would that stuff eat away the foam in the core of the boom?

foams only thier to stop it filling with water any ways

Mike105 said...

Had the same thing on a new boom after first use and fresh water wash. Usually take tail out completely to wash and suspect it is putting them back together wet (a type of crevice corrosion?). Since then I just leave it in two pieces until next session or completely dry - no problems on my other boom (purchased about the same time).

Have also got less a**l about washing gear every time and still no problems.

Also it was a cheap ally boom so coating maybe not the best.

I really don't know if it is a problem. All alloy corrodes and has white stuff on it.
I have never ever washed a boom and had 4yrs wavesailing from an ally Chinook. At least 3 masts were broken and 15 major sail damages and the boom is still good.

^^^"The long-term active ingredient is a non-volatile, viscous oil which remains on the surface, providing lubrication and protection from moisture. This is diluted with a volatile hydrocarbon to give a low viscosity fluid which can be sprayed and thus penetrate crevices. The volatile hydrocarbon then evaporates, leaving the oil behind. A propellant (originally a low-molecular weight hydrocarbon, now carbon dioxide) provides gas pressure in the can to force the liquid through the spray nozzle, then itself diffuses away."