Human Powered Boat

[Skippy]

SG, what do you think about the super-low-beam approach? You need a self-righting hull, and any shape that's geometrically stable upright will also be stable upside down. You also need fully enclosed, so why not a circular section? WS will be less, wavemaking is much less, and the extra height allows you to strap all your dense heavy gear to the bottom with a slightly better lever arm. The main tradeoff of course would be tenderness. But the total section can be so small that the vessel is submerged say 60% when fully loaded at the start of the trip, and 40% at the end, also decreasing windage. With your 1/4 horse engine, you just might be able to maintain a couple good steady knots. And of course, the higher speed would reduce your cargo requirements.

[mackid068]

Well, what if it doesn't actually right? Then you'd want some sort of inflatable device on one side of the top to push you back over, or just a way to escape. How about outriggers as well? Oh, and for stability, how about a box of water and a transfer pipe with another box to balance out the vessel?

(box of water is = sign, pipe is -) so, =----------=

[SolomonGrundy]

Well, all of what you said makes sense, but I'm an Aluminum boatbuilder and I'm trying to stay with a chine hull for ease of construction and to keep the costs down. A designer I have been working with said it would take >$25K just to get to the cutting files, before I could even turn on my welder, so I'm exploring other options. Thanks for the input.

[SolomonGrundy]

BTW, I intend on having a few fenders, so I can stow them on the top of the house on CL to aid in righting. Capsizing isn't too bid of a concern of mine anyway as the weight of water, batteries, stores etc. will all be down low and the boat will have level flotation installed with blue foam.

[mackid068]

Ok, I just am worried, sorry. Just a neurotic mess But safety is important. Good luck!

[Sean Herron]

Hello...

More than 25 grand to goto CNC cutting files...

I hope you don't use this person as a part time real estate agent on the side...

Yusus...

SH.

[sharpii2]

Originally Posted by SolomonGrundy

Well, all of what you said makes sense, but I'm an Aluminum boatbuilder and I'm trying to stay with a chine hull for ease of construction and to keep the costs down. A designer I have been working with said it would take >$25K just to get to the cutting files, before I could even turn on my welder, so I'm exploring other options. Thanks for the input.

As indeed you should.

If the craft were made out of flat plates bent on only one plane with little or no twist in them, it could probably be lofted up in one long weekend (labor day?) This may be an old fashioned way of doing things, but I bet it has lasted this long because it works. George Buehler has an excelent discription of the process in his book BUEHLER'S BACK YARD BOAT BUILDING.

Although I have never done it myself (at least for a whole boat), it seems straight forward enough to me. My next boat (of my own design, of course) will be built using this proccess.

I am waiting in anticipation to see what design you choose. Will it be a dory?
Or will it be similer to other ocean crossing human powered boats recently built. Just for s#@ts and gigles I dredged up my PLYBOATS c file for a design I had posted on page 4 of this thread, Added half a foot to its Beam and increased the rest of the dimensions accordingly. This produced a 27 footer that draws a little bit less than a foot and a half fully loaded and displaces a little more than three thousand pounds.

The problem I see with a dory is that the wind may tend to boss it around. With the ends being higher than the middle, it may find itself sideways to the wind in blowing conditions with you peddling like hell just to keep her in the right direction. Working dorys seemed to have been much smaller than what you have in mind. And the 16-17ft banks model had two oarsmen on board. Not only that, but they left the mother ship damn near empty and returned full of fish under sail when ever possible.

It appears that larger dorys were primarily sail driven.

That being said, their bare bones functionality and stark simplicity has always appealed to me as an alternative to the fancy floating furniture that the rich commonly refered to as yachts.

Bob

[mackid068]

Dory hulls are quite pretty. Brewer designed a 27 foot dory with a small diesel and said that it performed well in reality. I dunno if he's lying, but dorys are nice and stable (good reserve stability).

[SolomonGrundy]

I doubt that Mr. Brewer was incorrect, they are one of the best hull types for certain applications. I'm not going with the dory design, because: a) my prop will be relatively large for my length and b) I'm trying to keep the shaft length to a minimum, so a flat bottom (dory type) is less desirable. If I were to keep the same basic hullshape, only make it with a "v" bottom, and double ended, I gain a few inches in which to sink the shaft lower, and thus keep the whole prop. in the water at all times.

[mackid068]

Dorys are not flat, ncesessarily. They seem to have a slight v, but try a nice, deep V.

[SolomonGrundy]

Please correct me if I am mistaken, but are not all dories by definition flat bottomed?

[Skippy]

I think the dory bottom is fairly narrow (I'll skip the off-color joke ).

[mackid068]

A conventional dory, yes, but not ALL dories. A more conventional dory has rocker fore and aft but lacks a V. Many dories, however, have V-s.

[safewalrus]

By definition a dory has a flat bottom but....... some bottoms is narrow some broad. Some has steep sides to make the 'v' some has shallow sides which don't look like a 'v' but all of 'dem has flat bottoms. Just look at your banks dory and your swampscott twoo totally different worlds but not as far as you would at first think! The bottom is the thing! Flat it is! Just like the earth, you'd fall off else!

[SolomonGrundy]

After discussions with various designers and boatbuilders both locally and abroad, it seems like real progress is being made on getting the hull built. I've had lots of advice of varying quantity and quality, but its looking as though this boat could be launched this winter or spring. A few of my exemployers have stepped up to the plate to help me out and their help is greatly appreciated.
I'm off to go weld on a boat up in Dutch Harbor for a few weeks, so as usual, things are on hold while I try to earn enough to support my boatbuilding habit.
Another interesting addition to the team is Pro-Video Productions out of Erie, Pa. who will be keeping a video log of the entire effort from plate delivery to a champaign drenched homecoming.

So for anyone who reads this, know that this project is moving forward and we need all the help we can get. And no, we're not asking for money. Right now, we have key support with a great team. In the future, we will have other tasks to overcome, such as equiping the boat, logistical support, technical support and most important of all moral support. So if you or someone you know think you might have something positive to introduce into this effort...you know where we are.

Again, Thanks to all who have helped and contributed so far. I've had valuable responces from 6 continents. And the knowledge gained has been enormous.

More to follow. SG