Powering a wooden raft?

I am planning on making a large wooden raft with either pontoons or barrels underneath to keep it floating. I want the raft to be pretty large, it is going to have a canopy for the weather and spots for storage. I would like to have it pedaled powered,however a pedal wheel might be to hard to move the raft and it would scare all the fish away. Maybe a right angle propeller, but that would also be to small? Any ideas or tips would be appreciated,
Thanks,Nate

 

Welcome to the forum.

You questions are about a design, who's description is too broad to really answer effectively.

A "large" raft wouldn't be easily pedal powered, without some pretty serious gearing. Pontoons or barrels aren't the most efficient things going, so your losing just with this choice, right from the start.

Maybe it would be best if you offer some idea, as to what you think a large raft would be, it's likely construction, probable weight, etc. and we can work from there.

 

Pars points all make sense.

Unless you already have the barrels, or can get them for free, you will find that building a simple boxy hull from good quality plywood will be quicker, easier to propel, lighter and be a much better solution overall.

By the time you have mucked around with fastenings, waterproofing, ect, a proper hull is a way better solution, even if you could get the basic flotation devices cheaply.

 

Why muck around drifting and peddling and going no where in a hurry . live a little and get on with it !!
Make a big bracket and mount a 150 hp outboard on the back make sure the barrels run fore and aft so its eazy to push through the water and go for it !!:idea:.

 

Agreed Tunnels, pedal powered rafts, maybe 55 gallon drum pontoons. Please, pick up a used 50 HP outboard, toss a tune up on it and have some fun. Pedaling is for poor folks.

 

My plans for the size of the raft are roughly 10ft wide X 15ft long. Im not sure how i should make the hull,because I want it to be flat so I will need some sort of pontoons to support it? Also for the powering of the raft I was thinking it doesnt need to go really fast, I just want it fast enough to cruise around a little and do some fishing and exploring.

 

RWatson has described the most sensible solution. He mentions a boxy hull as a practical and functional option. He is talking about a barge. That would be an easy enough build and would not require a lot of power for propulsion. One of the 10 hp outboards would be entirely adequate to propel such a boat/raft/box.

The barge layout gives you a lot of options for storage within the hull which is not practical with drums or tubular pontoons. Reduce the width to 8 feet and the boat is trailerable in case you wish to move it. That width also simpifies plywood construction. A 10 foot width will be clumsy to move and to maneuver. If you cut the width to 6 feet it will more nearly resemble a boat and be easier to propel and to maneuver too. Explore the web and you will almost surely be able to find downloadable plans for barges that have been built before.

 

Thanks that is a good idea I will change the width to 8ft so I can just use normal pieces of plywood without cutting them.do you have ideas for dimensions for making a box hull,like a barge?

 

8X16 will let you use full sheets of plywood to make a barge. Look at http://upload.wikimedia.org/wikiped...-construction.png/600px-Punt-construction.png
http://t1.gstatic.com/images?q=tbn:...kI7547tbGED3QtfNUphP65ym9m74PbJvJDr1voJHAk0og

 

Thanks I will try to draw up some plans like the links.

 

You are not going to row or pedal a 8'x16' raft. You can probably pole one around for short distances, but only in very calm water. A second consideration will be volume. A raft this size will displace a lot, which you have to pay for in building materials and propulsion. Consider all your needs before drawing up a boat. Efficiency pays for itself in fuel, materials and build effort savings.

 

ok then what would you suggest for how I build one?

 

The build portion of the process is ways off yet. You need to establish what the design goals are first, so the design can address each of your concerns. What is this boat to do, what will its usual crew compliment be, target speed, thoughts on efficiency, accommodations, propulsion, electrical & plumbing considerations, the conditions it'll be used in, your building skills, materials availability, trailerability, local zoning, etc., etc., etc. This is the very first phase of any design (for anything).

 

For a first boat, simple, easy and worth building - how does this strike you ?

Its not as big as you first wanted, but it may be so much better thought out, that it will do a lot more.

If you needed it bigger, I bet the designer would do a scaled up version for you.

http://www.duckworksbbs.com/plans/jim/harmonica/index.htm

Harmonica
Plans - $27.50

Remember, every dollar you spend on calculations will save you 2 dollars on materials, and 2 hours on build time, and give you an extra 2 months of usability.

or more bigger, the blue boat below
Campjon
Plans - $32.50

http://www.duckworksbbs.com/plans/jim/campjon/index.htm

 

Look up bateau boats house boat 16. Simple build and roomy
I like the look of it.