Mast Leaks/small hull repair
Yup, here it is, another mast leak question. I have searched the forum for the other general mast leak questions, but this one is more specific.
After realizing that my mast was leaking, I thoroughly (or so I thought) sealed all rivets and mast cap with the heavy, white sealer/silicone recommended in previous posts.
But mast is still filling with water quickly following capsize. I've narrowed the leak to just below the mast cap at the top of the mast just behind the top halyard wheel (sorry, don't know what that wheel is called).
It's an alluminum mast on an '86 Nacra 5.0 and before drilling off the cap to see what's going on under there, I was wondering if anybody has any ideas where I'm leaking and whether the leak can be fixed without removing the cap. Is a cap a comp tip? Not sure what that is?
One other question if I may, evidently the keels on the 5.0 are a different compartment from the rest of the hull? I have to use 20 foot wooden ramps to slide my cat in the water off a 3 foot bank. The wood has worn the keel and has resulted in a small hole on the bottom, but I'm not taking on any water in the hulls while sailing.
Two quick questions, is there a quick, strong patch product for the keel until I can give it more attention at the end of the season? 2, I orginally had plastic latice on the ramps, but it was so slippery I could not control the cat up and down the ramp. Any suggestions about what I can add to the wooden ramps to reduce friction but at the same time not make it as slick as the plastice latice (plastic gutters nailed to the ramps?)
Dannno
For the small blind hole here is what I did. It was really easy.
I took a thin square piece of pressure treated wood (the biggest that would fit through the hole). I punched a small hole in the middle of the wood and put some thread through it. I slipped the wood in the hole and pulled it flush. I glued the block in place with super glue. I removed the thread. Then I filled the hole with “Marine Tex.” Once dry, I sanded it flush.
Matt
Danno,
Try putting marine carpet on the ramps - that should make some difference. Keel wear is a pretty standard thing and usually it is repaired by filling any holes and then putting an extra layer of fiberglass or kevlar on the keel. You can usually by a 2
wide roll of fiberglass (or kevlar) that works really well in this application.
Your mast cap is not a comptip - that is a plastic top mast section used on some Hobies and is about 3 or 4 feet long.
I'm not sure exactly what the top of your mast looks like but it sounds like you do need to remove the cap, reseal, and reinstall it. I'm guessing you have a cast aluminum cap that is recessed to fit inside the mast and is riveted in place? If so, just drill out the rivet heads with an oversized drill bit (1/4
) (being carefull not to drill out any mast material). Punch the rivets into the mast, remove the cap, apply bunches of sealant (3m 5200), re-rivet the cap in place...alumnimum rivets would be fine in that application - monel as well.


I was hoping to do this when I removed the bottom mast casting (broke when putting up mast when I tried to straighten it too early). But I found out it was sealed about 7 cm from the base! I can't imagine how many rivets are in the mast- but probably less than in the HULLS!!!
BTW... good luck with getting the cap off. I about had a stroke trying to get the bottom off fighting the sealer and tryingnot to destroy the mast.
Thanks all -
I did seal around the mast cap last season, but evidently, based upon the flow coming from that area when I raised my mast out of the water, you cannot properly seal the cap without first removing it.
There will be no plug or anything in the there that will have to be replaced? Just the cap/seal keep the water from entering the top of the mast?
Danno

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