Looking for ideas on building a PVC river raft

I am interested in building a raft for use on the Mississippi. I am about 150-200 miles from Itasca. My first idea was 5 gallon bucket pontoons but since then I have aquired access to a large amount of 4" X 6' pvc well pipes. Any ideas or suggestions would be greatly appreciated. Thanks- Rob

 

I would be thinking of a catamaran with 24' long hulls made from tube bundles of 4 tubes long. You could make solid bundles or just use the tubes on the outside with internal formers to locate the tubes.

Either way you would like to form a nice curve into a near pointed bow and stern on each hull.

The tubes could be sealed off with expanded foam in either end. Either pressure pack or bulk two part. The foam is easy to fair out with a rasp.

You could use expanded foam to fair out the circular gaps between the tubes.

You could then wrap each hull bundle in some cheap ployester fabric that is stretched over the hull bundle and clamped along a top seam. Then use polyester based flowcoat to stiffen it up, increase scratch resistance and improve surface finish.

I made a catamaran from two pieces of aluminium irrigation pipe. It is good for boats if you can weld it. Here is an example of a catamaran I made from pipe that has very simple hull form - just cones welded to tube to get a nice transition:
http://www.rickwill.bigpondhosting.com/web_photos_video/video_v4.wmv

Rick W.

 

Net flotation potential of a six foot length of 4" PVC will be only about 28 pounds. 28 pounds only if fully immersed and of course, capped on the ends. It follows that a 24 foot piece would support only 112 pounds. Rick W. is right that you can build it with pipe but I submit that you need to have an overwhelmingly good reason for doing it that way.

You are falling into the familiar trap of making a boat suit the material. A boat worth building uses the material that will suit the boat. If you want to build a raft or floatboat, then consider conventional material like plywood. That construction will yield a better boat, take less time to build, and may not cost as much as compromising the structure with alien materials or methods.