ok, i've shelved the lifeboat since it's too big for my engine(21'x7'2") (3ihp,or 2.5shp) and i've bought a woodboat (19LOA 'x 5.5'beam) similar in shape to the selway fisher snow bunting|(squareish stern) my calculation tell me that with the 400rpm speed of the engine i need a 15"diameter x 17" pitch propeller. am I right?
John
Propellers and hulls
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barts
- Full Steam Ahead
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Re: Propellers and hulls
I'm running a 16x21 on our 2.5"x2.5" piston valve engine; works very nicely at 150 psi or so. The hull is 19' x 5'...
If your engine is a bit smaller, you're pretty much on target.
-= Bart
If your engine is a bit smaller, you're pretty much on target.
-= Bart
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Bart Smaalders http://smaalders.net/barts Lopez Island, WA
Bart Smaalders http://smaalders.net/barts Lopez Island, WA
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johnp
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- Location: Richmond Hill, Ontario, Canada
Re: Propellers and hulls
The engine is 2.25 x 3 @ 125 psi
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barts
- Full Steam Ahead
- Posts: 1089
- Joined: Wed Nov 18, 2009 6:08 am
- Boat Name: Otter, Rainbow
- Location: Lopez Island, WA and sometimes Menlo Park, CA
- Contact:
Re: Propellers and hulls
Well, I'd see if I could find a bit more pitch, but if you have 15x17 already it will certainly work.
Our boat is easily driven; if yours is not then 15x17 will work perfectly, I think.
- Bart
Our boat is easily driven; if yours is not then 15x17 will work perfectly, I think.
- Bart
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Bart Smaalders http://smaalders.net/barts Lopez Island, WA
Bart Smaalders http://smaalders.net/barts Lopez Island, WA