How tough IS the bottom of our keel?

[ebb]

Ariel 338 MAY have similar thickness on the very bottom edge of the keel. I would not bet on it. When the encapsulated keel cavity was drained and filled there was plenty of opportunity to visibly see the thickness of the hull.

The thickness of the hull was never more than 3/8".

In the back of the keel forward of the rudder there may be a too high percentage concentration of polyester to fiberglass for good strength.



An Interphase probe was installed low in the stem requiring a fairly large hole for the sensor. The thickness of the stem was just about the same.

[frank durant]

Ebb When I was drilling drain holes on #50 , 2 holes on the side of the keel , both approx. 7in up from the base , showed a thickness of 3/8 - 7/16. I installed a new through hull for a raw water pick up for the sink just before the "turn to the bilge" and it showed 5/8. I suspected the 1 1/8 to 1 1/4 I found at the forward base of the keel was due to overlap of roving . ??? Any thoughts?

[Bill]

It should be noted that in earlier numbered boats the hull thickness may have been greater than in the later numbered boats.

[ebb]

There you go Frank.
Very very good quality polyester obviously was used by Pearson in the '60s.
Grinded a whole lot on the laminate and it is real tough stuff. The resin to glass schedule to my amatuer eye looks right every accessable surface inside the hull. I've seen no puddling or starving. The only real problem with saturation (and fit) was at the lazarette bulkhead - everyelse the laminate is good and strong.

Along with the stringer and its tabbing it is probable that the tabbing used by the factory to hold the cabin sole and settees and bulkheads in adds significant stiffness and strength to the hull. Guess the schedule for the hull laminate totaled out at 3/8s with tabbing and overlaps adding 1/8" or more in places.

Navy did tests a decade ago on old frp barges they had. (Have to assume the polyester was similar to Pearson's.) No deterioration in overall strength was found. Would think the more active hull of an old sailboat would be a good indicator. In itself the laminate is as strong as the material can get, imco.
On the right reef, or picked up and thrown at a piling by a comber, I would call on the luck of 'The Way' and a pinch or two of 'Ave Maria' to save our butts.

[frank durant]

Bill , Ebb I'm sittin here thinking and when I drilled for a new head discharge the hull was 3/8. What I found was VERY inconsistant thickness's. Forward 3/8 just below the waterline ,forward high on the topsides,my anchor locker drain hole 3/8 , aft 5/8 below waterline at the turn or the bilge ,side of keel 3/8-7/16 , and the 1 1/8 at the forward base.???????But back to the original question.....at low speed I still doubt much damage other than paint.

[willie]

Frank, it's a nissan NS5B. 5hp long shaft 2stroke, weighs 44 lbs.Through the prop exhaust, no problem with the lid closed yesterday. Very little exhaust at all noticable.

I think where she ran up on the rock is a pretty solid and tough area.(the boat! rock too for that matter!)
I remember drilling drain holes around the keel while on the trailer, but couldn't get to the VERY bottom. You know, what she sits on. I can imagine it being pretty darn thick under that lead, having an idea of the mold, glass, resin...building process. .and the overlap you speak of. It supports the whole weight of her on the hard, so can't imagine it doing much in the water where the majority of the boat is still afloat. But we are talking HARD basalt rock here. And maybe 1/2 knot. 5 knots? Yeah, i can imagine some damage.
How hard is coral?

If i did hole her, the ballast cavity would fill up first, right? Guess if she's still afloat when i go down tomorrow, i'll feel better. Sure a sick feeling hearing and feeling her hit. I can't imagine being the skipper of a 90' schooner, 30 yrds. off the beach and having it happen. Churn churn.
I see they got her off last night.

[Mike Goodwin]

"There are two kinds of sailors, those who have run aground and liars !"

Welcome to the club!

If you haven't run aground , you haven't done enough sailing.

[ebb]

Frank, A frp sailboat should gradually get thicker from the sheer on down. 338 is not much more than 1/8" at the seam. But seemingly only getting to 3/8" down in the keel. That is what is so disconcerting, 338 seems to be very conservatively layered, if you can call it that. Even the transom is barely 5/16 in the center, fattening out in the corners and the tabbing across the top.

The hull/deck seam is thickened by the mat tabbing. (On 338 the toerail molding is now filled flush to the inside of the deck.) A test hole thru the topside in a chainplate area yeilded 3/16"
There is considerable factory tabbing of the cabin decks, bulkheads, settees, stringers, although the tabs seldom go further than 4-5" from a joint, which may accouint for varying thicknesses of the hull in proximity. The old cockpit drain holes showed the hull to be around 3/8s.

I feel a little better that the keel cavity is filled with epoxy and there is now a built-in watertite tank running the length of the cabin over the ballast in the turn of the bilge. 338's (supposedly) lightly built hull will have all its furniture tabbed in and probably a layer of 20oz xmatt (about 1/16" thickness) most areas below the waterline. Insurance???

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Maybe somebody knows just how hard or sharp coral calcium is? Probably harder and sharper in the tropics! What will it do to the hull of an A/C? Has anybody seriously run onto rocks? What damage occured? Pictures? More than curious, would like to hear and see what the A/C hull can take!!!