sailing skiff with an 8hp.

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Coolredmudball
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sailing skiff with an 8hp.

Post by Coolredmudball »

I am wanting to build myself a small boat. I already have an 8hp 4 stroke Yamaha outboard. I'd like it to motor at a reasonable speed but also have the capability to sail, though with our rivers I'm guessing that would be at a minimum. A small cab would be nice as well. I had thought of a Scamp but the folks on that forum convinced me that 8hp was WAY too much power. Any suggestions? Thanks for any and all ideas.
hankstamper
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Re: sailing skiff with an 8hp.

Post by hankstamper »

you may want to think about a goat island skiff, or perhaps some kind of modified sharpie design; skipjack, etc.
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PAR
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Re: sailing skiff with an 8hp.

Post by PAR »

The problem with your "SOR" is conflicting desires, which is a common issue. A small sailboat will do in the 5 to 6 MPH range, unless it's a performance oriented craft, able to plane off. These might see low double digit speeds and a really fast one, possible the mid teens (MPH). These are skittish boats, that sail on the edge and wouldn't like an 8 HP outboard hanging on the transom. Except for the full plane mode sailors, the hull shapes of the typical sailboat, aren't well suited to speeds much over the single digits you could get from them. If pushed faster with a big HP engine, they become progressively more unstable as the speed rises, again, because of the shapes employed in the after sections of the immersed portions of the hull.
Powerboat hulls differ considerably in this regard (aft hull form shapes), providing "bearing area" for the boat to scoot on. This said, some hulls are better than others, but a good look at the buttocks and waterlines aft will be necessary to judge if it's better suited for being overpowered into semi-plane or full plane mode operation. Scamp isn't well suited for overpowering. A flat bottom hull with much of its aft rocker removed, will fair much better in this regard, though you'll have to sacrifice some sailing abilities to gain this feature.
Another way to look at this is how much "power" does the rig provide, so you can appropriately size an engine. 50 sq. ft. of sail area is approximately 1 HP. This means the Scamp has 2 HP of propulsion potential in its rig. From what I've seen, this more than adequately pushes this puppy along, so quadrupling this propulsive force, just isn't a viable option. Don't get me wrong, on a hot, windless day, with water temperatures in the high 80's (normal for me) a few quick blasts at likely uncontrollable speeds and very questionable stability, would be fun, until you scared yourself back into reality. As a young man we did this fairly regularly, with the expected mixed bag of capsizes, rolls, drowned motors and sunk little boats, that had to be dragged back to shore by the more responsible among us (our pissed off dads usually).
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