20' Motorsailer

[newinertia]

Well I needed to fit the boat with eigther human power or a trolling motor for a backup form of propulsion- I have been mulling this design over for a few years now and yesterday morning i decided it was the time to build one, so with only the parts and supplies I had on hand, I built this.....
The tuna fin pushed me at 1.6 mph on gps, boat is filled with a weeks worth of food and clothes, stove, 5gal water, 5 gal gas, 17hp Kohler engine, toolbox..........etc. Id say she is a fine shantyboat! the outer hulls are Hobie Cat 16, center hull is a Catalina 15 Capri. Spars under deck are 304 stainless 2"x2"
Also- this was a float test for the amas and main hull, c/b wt/balance.
Special Thanks to Mindy- my girl.

[newinertia]

this is what I started with.




tags:
Sailboat recycling sailboat conversion anti-sailboat brigs and stratton boat
engine air cooled lawnmower engine mated to a lower unit inboard trawler mini

[rwatson]

It may be a shanty boat, but why do you need to suffer with that extended rudder ?

It must make it very heavy to do a tight turn

[newinertia]

Thats not the rudder, thats my yuloh, they use the same mounts. why dont you read posts before putting in your self riteous two cents- and passive agressive shantyboat comments. I can call it what I want, you cant.

[newinertia]

Ok as you know, I got rid of the junk tecumseh engine because it was impossible to keep synchronized at idle speeds, wide open it was a powerhouse, but low rpm, effortless efficiency was the goal.
I traded it out for the KOHLER Courage single cyl. 17hp. engine. (lighter)
It produces about 4 amps of 12 volt dc current at 800 rpm, and with the reduction belt drive, I am seeing 5.4 mph at the same 800rpm. With the 10x12 prop, I wanted to do a measured fuel test, so I marked a container with accurate marks for measuring. I started with one gallon of fuel and a gps to find speed and range- its close enough for this work. Every hour I marked the level on the container- the ONE gallon container, it took me six hours and 25 minutes to burn that same ONE gallon. (6 hours 25 minutes.) GPS average was 5.2 mph, there was a 6-8 mph breeze and it was a 2-way average. the rear pontoons were removed, so it was just me and my dog and about 100 lbs of gear. top speed recorded so far was 12.2 mph- and that burns alot more! (different day) so- Im sure Im going to be called a liar by a bunch of you, but it shows that a 30 mpg boat is possible for cruising- do the math.
and please start designing boats like this- there IS a market!!!!

[Norsehammer]

I love It! Do you still have the sail rig?
It could be fitted to this vessel and you'd be motor sailing a trihull...
There is new and different life to older boats with this kind of enginuity

[newinertia]

Thanks Hammer-
I was sold the boat and trailer for $100 because all rigging was removed, possibly stolen for crack money..... I would really like to fit it with a 12 meter kite, but they are expensive.

[newinertia]

Lake Jacomo