wood pedal boat- idea

[molerocket]

Hello, all. I'm new and came here because I have a hankerin' to design and build a ply/glass boat powered with foot pedals.

i.e. bicycle pedal that somehow drives a propeller.

the length would be 10-12 feet, something like that.

1. possible?
2. crazy?
3. would foot power even make it move?
4. where might i find parts to rig up the pedal/gearing assembly?
5. i know that many inboard engines have a propeller shaft that goes from the inside to the outside of the hull without the boat leaking. how can I do this with my propeller shaft (i.e. what is the secret, how does it work)?

thanks so much,
molerocket

[duluthboats]

1 Yes
2 No
3 Yes
4 Google HPV's, this site also has many threads on the subject.
5 Depends on the type of craft you choose.
Gary :D

[marshmat]

First three: yes no yes, as per Duluth.
4: Certainly look up some HPV stuff which this place is loaded with. Try bike shops. The lower unit of a dead 2hp outboard can serve as a bevel gear to get a longitudinal shaft from a lateral crank. Have a way of changing the gear ratio (ie bike sprokets), at least until you settle on one that works.
5: The device you refer to is called a "stuffing box". It's just a tube around the shaft, that's bolted/sealed to the hull, and is filled with special water-resistant packing that seals the gap. It does add some friction to the system, so you might consider looking for sealed waterproof ball-bearings instead.

[Chris Ostlind]

Molerocket,

Take a long look at this device designed by my buddy, Bob Stuart... The SpinFin. There's a short bit about the unit here: http://microship.com/bobstuart/pix/drive%20unit.JPG

Bob has put these propeller drive units into several types of boats with very good results. I have driven one of his sea kayaks with the trunk mounted SpinFin in it and it hauls ass with little effort for a person in shape.

Bob can be reached at: bobstuart@ssisland.com He lives on Salt Spring Island off Vancouver, Canada. A great guy, very personable and seriously smart with all things engineering related for human driven boats.