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[Rob]

Have had an opportunity to sail the new wood boat a few times, and I'm starting to have problems with water coming up through the centerboard trunk...a lot of water. Especially on a plane. Like a fire hose sometimes. I'm assuming that there is some sort of gasket applied to the bottom of the boat that seals around the CB when its in the down position. We have something similar on our Flying Scot Class boats. Made of very stiff dacron. Is there someone who makes these and sells them, or do y'all make them yourselves? How are they installed? Any help would be appreciated.

[maxibuddah]

most of our boats use a stiff mylar tape. You have two pieces which butt together down the centreline of the slot. Glue them at the front, back and either side and the board will slide down through them.
http://www.sailboats.co.uk/productinfo.aspx?productID=577270
or
http://www.pinbax.com/index.asp?selection=detailed&uid=32436&cg=1&mc=10&cct=&sc= - this shows the construction of the tape better

Another method is to use two pieces of dacron with an overlap, where the board slides through. As the material is softer it works well with a slight overlap. If I remember correctly on boats I've seen it on, each side piece is basically a bit the same width as the total which is then folded in half throughout its length with the creased edge forming the slot. With this method you will need to screw it down with some sort of capping to trap the dacron.
http://www.sailboats.co.uk/productinfo.aspx?productID=577250
Best of luck in avoiding the geyser

[Rob]

Max, thanks for the help. The links were very helpful. I had been discussing using a mylar laminate and adhesive with our local sailmaker, and I think we'll try that route first.

[maxibuddah]

rob, it is also worth making sure you get a good amount in front and behind the slot, say 2". another good thing to do is to put a length of thin tape over the front of the foremost part of the gasket so that it doesn't lift at any point. Also make sure that a certain amount of the front is not stuck down as normally the front of the board butts up against the front of the case otherwise it will split the gasket across ways

[Rob]

Will do. Saw that in the directions for applying one of the Hawk products I think. Looks like it should be pretty simple to install. I'll let you know if it fixes "Old Faithful".

[OultonBen]

Some stick down the mylar tape, then when cured and firm (24-hr), use a very sharp knife to slice down the centre-line.
Risk is (a) cut is not straight (it's ever so easy for the knife to 'wander', even when you think you have a hard-edge to follow !) so offering-up soft-spots for the c/b to catch on and bend, or (b) any pause in the cutting produces an imperfect slice with a small nick that again can catch the c/b.

Alternative:-
Using over-long tape pinned down onto a long firm plank, cut down the centreline of the tape, then stick tape (shortened to correct length) with original (outer) edges meeting at the centre, or even overlapping by ¹/₈ inch (but no more).

I used to do the 'alternative' very successfully on Fireballs, but have recently become lazy, accepted the risks and employed the "stick then cut-down-the-middle" technique.

For both, a small "V" at the stern end helps the slot empty by venturi effect, just like a self-bailer.
Also concur the importance of a ~3cm length of non-stuck at the front end to allow flexibility when the c/b is fully down, and a short transverse sacrificial piece to ensure leading edge stays down (for this I use the brilliant Conservatory Roof Repair Tape (Mylar) described elsewhere).

BR
Ben

[OultonBen]

From your original post Rob, I'm not sure if you know of C/B slot gasket tape.
This is THE proper stuff; don't use anything else.
It has the right thickness/stiffness/recovery that other sailmakers' stuff doesn't really match that well at all.
It comes in two widths and you buy it cut off by-the-metre. Make sure you use the right width (75mm) !

Ben-again

[maxibuddah]

Ben, I tried the cut the middle trick and had the same difficulties with the wandering of the blade, but it did a job on my old boat. Jeff's little helper years ago on my current boat when it was being built used two pieces to save having to do.just that butter together along the length, and its still on the boat still working 7 years on.

Rob was talking about the hawk stuff I linked to so I'm guessing he's using the right stuff

always a pain, but which ever way he does will better than he has now

[Rob]

Centerboard gasket on and works great! I used a single piece of heavy mylar sail material, and attached it to the hull with double sided adhesive tape. The tape failed on forst attempt, so I went back and sealed over the edges with duct tape, temporarily. I cut the gasket out per a pattern I made up beforehand, and then made the center cut with a good, long, metal straight edge. I then applied two patched of dacron at the front and rear of the slot for reinforcement. Also, I did try cutting a small triangular opening at the very rear of the slot as a suction bailer for the trunk. It actually worked pretty well when the boat was up and moving. The boat is put up for the winter, but I'm going to re-apply the gasket next year using West System 5200 adhesive. I did get to sail yesterday in our last handicap fleet race, and probably won the first race on corrected time. Just had an fantastic day of sailing the Phantom, and really looking forward to next Spring. Meanwhile, US Phantom #2 will be under construction over the winter.

[PeteSykes]

I have a patch of clear sticky backed plastic at the head of the slot gasket extending a few inches ahead of it and to the side. More surface area stuck down around the part where the mylar inevitably lifts so more likely to stay stuck. I've not had half the slot gasket problems I used to have on the Blaze

Works for me

Pete