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I bought a 1992 Super Snark to take on local lakes here in Washington. I last sailed 35 years ago in college. Yes, it's like riding a bike and as fun as it was then! :)

Sadly though, I found that my little Snark VIBRATES when we get a decent puff of wind. Wind was scarce that day so I didn't get a chance to find the source. I felt it mostly in the tiller, though the body of the boat vibrated too. I notice that the daggerboard is quite loose and the board floats up a bit in its housing. The rudder seems snugly bolted to the tiller.

I'd like to take it on vacation this weekend with the kayaks - but not unless I get this solved. It's pronounced enough to be disturbing - sort of feels like the boat's about to break up.

The hull is in decent condition. This boat is < 50 lbs, so I expect it to feel a bit 'fluffy', but I did not expect it to shake this way. This was not a stiff wind - just enough breeze to sail along.:cut_out_animated_em

Any input is welcome.
I just want to have some fun.
 

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Welcome to SailNet!

Did you notice if the vibration happens on only a certain point of sail? When we had our 22 footer the swing keel hummed at certain times. That was normal for that boat.
 

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Freedom isn't free
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The centerboard on the snark lets you know when you hit hull speed by vibrating like mad... Consider it a rite of passage. If you can get the spars to stay straight enough, downwind, and you sit far enough back in the boat, you MIGHT be able to get that vibration to get REAL high pitched JUST before it stops, as the boat launches on a plane! Yep a SNARK planes! I was much smaller then, might not be easy to do if you are over 150lbs.

I found that sailing before a pop-up thunderstorm downwind can give you enough wind to get you there... only problem is keeping the rudder from falling off (since its merely a paper clip holding the rudder on with that joke of a pintle), the spars from bending in half, and preventing wetting yourself in laughter (you know beyond the wet keester you'll already have from the sloshing water in the bilge you are sitting in).

Yep, nothign to see here, or rather hear, here. The styrofoam model the vibrating is lough enough to hear it hundreds of feet away!

Oh and I'll bet ANY of the sailors who learned on these, will confirm what I am saying if they ever REALLY sailed their snarks. Lemme see if I can update this post with my favorite BLUE WATER SNARK picture.
That's my brother (at 45 yo) sailing my Snark (at that time it was 30 yo) on the OPEN OCEAN (OK not far from the beach, but damnit it WAS ocean!)...



Whatever you do don't sell the boat, by all means upgrade when you are ready, but keep the boat, if nothing else to use as a dingy.
 

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FYI my brother ruined his cellphone that day, in a ziplock bag, sloshing around in the bottom of the boat. I helped him drag the boat from the shore house we were renting down to the water, some 400 yards or so. I lied, that was his $100 Super Snark that he bought, even though he had both my old boat (when I was 11 the all foam Sea Snark) and this one (the ABS plastic coated Super Snark) with him, he decided the ABS plastic would hold up to the wave pounding better than the styrofoam one :)

I'm pretty sure that 50lb snark, was 150lbs laden with trapped water between the ABS plastic and the foam core though. It saw better days for sure. Also that sail, he made himself, as apparently mice ate away most of the prior sail.
 

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I used to sail Lasers and they vibrated like mad at hull speed too. With the Lasers we used to pull up the centreboard to stop the problem since we were always sailing down wind when it happened. We sailed behind a mile long breakwater with 20 knot breezes and 4" waves which made for fantastic speeds.
 

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Lots of daggerboard and centerboard boats vibrate (sing!!!) at high speed. Most all planing hull boats vibrate when on a 'screaming' plane. Sailplanes / gliders also 'whine' when the wings are heavily loaded during flight, especially at the 'bottom' of a diving 'loop'. A lot of ice boat sails (and runners) 'sing' when at super-high speed.

There are several conditions ongoing at the same time 'in boats':
1. The 'board' is too thin (not correctly hydro-dynamically shaped, usually too thin; but, 'thicker' is slower); and, the thin board is quite subject to induced harmonic vibrations - the same process that makes a violin string sound a note when its bow is drawn across it. The 'stiffer' the board, the higher pitched the 'hum'.
2. Vortex shedding across the leading and trailing edges of the 'board' (and sailplane wing) - the vortexes being shed are 'regular'; hence, at a specific resonant frequency. The 'sharper' the leading and trailing edges of the board, the higher the vibratory amplitude.

Most of such 'racing class' boats in this category have very strict rules on how 'sharp' these board leading and trailing edges can be. The early planing hull ILYA scow boats of the 1890s had razor sharp edges to their bilge-boards.

So, if your boat and/or 'board' is singing/humming, welcome to a very unique class of 'very fast' boats. Enjoy 'the music' !!!!
 

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Rich, your technical expertise is as always a step above...

Just for the record, the daggerboard on the Snark is a chunk of 1/2" plywood (might even be 5/16"), with a 10" radiused bottom, if you are LUCKY, the edges are "rounded off" with a file :) There is no "tight fit" for it either, so it rock fore and aft in the slot, the ONLY thing that keeps it from popping up all the time is forward movement of the boat (it wedges it against the ABS/Styrofoam). There isn't even a good spot to put a bungie to hold it down (like in the Sunfish or the laser). If you are lucky enough to have the ABS plastic model Super Snark (as does the OP), you MIGHT be able to install a padeye and a cleat. But keep in mind if you do, it'll very likely leak, now you'll have water trapped between the ABS plastic and styrofoam.

By contrast the Laser, and the sunfish, have perfectly shaped hydrodymically shaped "foils." In that at least someone decided to TRY to taper the edges a bit.

The Snark is proof that sometimes the simplest design wins.

Ah yes LOVE The internet.... HERE you go, a HIGHLY ADVANCED foil for the snark! Still the best darned boat to learn on! You can fashion your own parts!
 

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snake charmer, cat herder
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you DO realize the snark is a styrofoam boat with very thin plastic shell, dont you?
wind will create vibrations and songs when the frequency is right for each different line or cable.
these vibrations , in a larger more solid boat, can be minuimally adjusted out , or changed to perfect the tune. there will always be some.
snark is for very very light wind. oops, not wind but puff of air. perfect for small pond.
my neighbor had one in san diego bay. it lasted almost 3 months before it broke up. it iS styrofoam.
ye may want to save up for a more solid dink, something along lines of hobie 12 (monohull--awesome fun sailor)or a kite (newport 11) or the newer versions of olympic sailors mentioned above. or an optimist or sabot.
 
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