If you have a mast on your trawler or powerboat, it will eventually need either repairing or at least painting. The nature of paint on aluminum in a marine environment dictates this. It can be delayed by judicious care – such as touching up scratches as they occur or taking care of corrosion at fittings. Although we don’t see as many damaged masts (as in the photo above) we do see a lot of paint damage on them – usually caused by corrosion. It can start as a scrape from another piece of equipment or a fitting that was not sealed properly. In any case the corrosion will travel once it starts. Once you see the damage you should hasten to seal it up before it travels. This can only be accomplished by sanding the corrosion back to bare aluminum before sealing. You don’t want to seal the corrosion under the paint. Most of the ones we see are already to the point where they need repainting any way so we like to do it right. Remove the mast and all the rigging as well as any attached hardware and get down with a sander. You will need to hard sand in some places and merely scratch for new paint on most. You can apply Awlgrip over already areas that already have the same paint but we prefer to prime the whole mast for a uniform finish and just to be on the safe side. If you have removed hardware, you should fill the holes that were previously used – you don’t want unused holes in the mast to be a channel for moisture intrusion. This takes a little planning if you haven’t picked out your electronics yet you may want to do that so you don’t end up with extra holes in the mast later. It is best to have the holes drilled first so the edges will be encapsulated in paint. If you drill after painting you should use a bit of paint on the bare edges to seal it up. When installing brackets for electronics and the like we prefer to build them from aluminum and weld them on before painting. This not only looks better and more professional but eliminates fasteners which will compromise the paint. When you do use fasteners you need to isolate the fastener from the aluminum. Even stainless will eventually cause corrosion. You should use an isolating compound such as Never-Sieze We use grommets where the wires go through the holes. This protects the edges from abrasion – once again permitting water intrusion under the paint. With a couple of good coats of Awlgrip and some careful rigging your mast should provide you with many years of service with no maintenance except for the occasional inspection.
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