Building a Raft

Hi

I know you probaly get this alot, But we are doing a raft race for chairty,

The raft needs to be able to be light or be able to go down wiers, it needs to hold 6 people and be easy to steer and be quite fast in the water.

We would like if possible to also make it peddle powered but are not to worried if we cannot.

Does anyone have any ideas?

 

Not sure if those designs might work, but should give some idea's

https://www.boatdesigns.com/Human-Power/departments/8/

http://www.chrisharrison.net/projects/alleghenyrafters/index.html

Hopefully a more experienced member would give you more info

 

Rafts are inherently not the easiest things to steer. Nor are they fast. They are primarily designed to float with current and not really fast current at that. That being said...a light weight raft could be done with blocks of foam glued together and sandwiched between cheap plywood sheets-thru bolted with some allthread to keep things together and provide some protection for the foam I would go with 6 ft wide and 12 ft long using 2" sheets of foam stacked say 8 deep, 1/4" ply for the top and bottom. Make a large barn door rudder to steer it with and make sure it projects around 6" below the bottom at the deepest but slopes upwards as it goes forward so it slides over things. You want pedal power? mount a bike in the middle, take off the back wheel and mount the sprockets to a shaft and make it a paddle wheeler.

 

Simply steer it with differential thrust. One side pedals more than the other.

I believe the term "raft" is being used loosely here...

-Tom