Team Seacats

It’s time to really start thinking about some of the big races we have coming up.  Last week, I took the cover off and spent an evening inspecting the blue Team Seacats Nacra 20.  Everything looks good except that I found one of the shroud tangs (a stainless steel plate that holds up the mast!) was loose in the hull.  I could wiggle it back and forth and side to side and lift it up and down almost 3/16″.  Not good.  I put in a call to Performance Catamarans and after a conversation with Jack, I had a better understanding of how this plate is configured.  The plate is t-shaped and has some holes through which some heavy fiberglass tow is run and resined to the hull.  Then a cover of some heavy knit fiberglass goes overtop of this to make it watertight. Because the plate is t-shaped, it really shouldn’t be much of a failure concern.  However, the fact that it wiggles around means that it can continue to wear to the point that it may be a concern.  For repair, my hope was that it was watertight and that I would be able to drill a couple of small holes in the side of the hull through which to apply vacuum and draw in epoxy resin…but I wasn’t quite so lucky.

The recess in the edge of the hull from which the plate protrudes forms a great spot to seal off for vacuum….but I had a problem…the plate was not sealed inside the hull.  I took my camera and extended my arm up to my shoulder to get some pictures to see what was happening (thank goodness we added the forward ports last year!). I also trickled some water from the top to see if I could figure out where the leak was.

In the left-most picture you can see a trickle of water coming out from under the bunji tube (this is where the trapeze retention bunji goes through the hull).  The leak is not the buji tube but is coming through the tang (this would explain why this hull was taking on a little water while under sail).  Above this area, you can see a glassed in plate where one of the spinnaker blocks screws to the deck and the vertical structure to the right in the left picture is the front of the daggerboard trunk.  After running some denatured alcohol through the tang to dry up the water, I mixed up some thickened epoxy and smeared it over this leak with a gloved hand.

 

After that setup, I was disappointed that I still hadn’t found all the leaks, so I resorted to plan “B”.  Instead of drawing a vacuum, I would pressurize a cup of epoxy and force it into the hull.  I think this will hold as a repair – at the very least, it should seal up the leaks so I can pull a vacuum on it next.  I put a piece of tubing inside a piece of plastic spiral wrap – the spiral wrap will keep the sealing clay from clogging up the exit of the tube and the narrow entry into the hull.  I then pressed in clay filling up the entire recess and sealing in the tube.  I then rigged up a cup with some more clay and a top plate, mixed up some epoxy, and lightly pressurized the cup forcing about 4 oz of epoxy resin cleanly into the hull.

I did eventually find the other opening in the fiberglass backing – it is definitely sealed now (it was at the top where it mates with the mounting plate for the spinnaker sheet block) and the tang is VERY firm in the hull.  I’ll be sailing this boat at Spring Fever next weekend so hopefully we’ll give it a good test.