Boat Building

[andrewtexas123]

Hi am building a boat with my friends. It is actually a compatishion rules are the following

1. Must be under 100GBP

2. No pre made hulls

3. Must carry to people

4. Cant be over 11ft long

Thats it, the winner will be the first to make 3 laps around the lake and the race will be in less then a month and 1/2.

So my team has decided to build a wood structure and put sheets of ply wood around it to seal it off we will use expanding foam. Will the foam work?

To transport our boat we will be usein g a built in whell in to the bottem back so we can atatch it to the car from the front.

We will be useing the bigest, cheapest, working, and best fitting out board that we can find!

I need sugestions for hull types diagrams would not be bad and i will try to see what i can find and will post it up looking for it to be about 8 1/2ft to 9ft long.

pls post comments of aything

-Andrew

[Richard Hillsid]

Hydroplane

[safewalrus]

Build a box! won't be elegant but it will float and be simple to build! Doesn't need any posh curvy bits just a plain old rectangular box. Put a slope on the front if you must but it really isn't necessary! And put some flags on it (no purpose but it looks good!)

[Richard Hillsid]

Originally Posted by safewalrus

Build a box! won't be elegant but it will float and be simple to build! Doesn't need any posh curvy bits just a plain old rectangular box. Put a slope on the front if you must but it really isn't necessary! And put some flags on it (no purpose but it looks good!)

Agree totally, no slope necessary, a box is cool and ad some hydroplanes to it with the flags.

[andrewtexas123]

I went on to another fourm anad they flame me sayiong i nee plans, thanks guys.

I have already started and worked all Yesterday making the frame strong it is boing to be kind of like a d-day landing boat. The furthest point to pionit is 9ft width 4 1/2.

Thanks, Andrew

[china]

sounds interesting. under a hundred pounds. let us know what happens.

i am not sure about the foam. you might need a waterproof putty. resin and sawdust mixed together into a thick putty could do for the inside. any resin left could be mixed up with some fibre strips of material and put onto the outside of the hull frame edges and left to set. for extra strengh.but resin isnt very cheap. but maybe some one has better ideas for a resin substitute.

glen l have some stitch and glue online information to have a look at to understand the process and theory.

good luck and keep us informed.

[china]

you could try using rope and tar to fill the gaps. squeeze the tar covered/soaked rope in the gaps and tap it in with a tool and then paint over it with more tar.
a very messy and fiddly job. but cheap.

[kagraham]

expanding foam should work, it will form a water tight seal. When you buy it, if you dont already have some laying around that is, look for the type meant for window and door installation (it wont expand as much but is slightly stronger) also, make sure you have some acetone, because that stuff is ALWAYS messy and there is no easy way to get it off anything. I would recomend getting some cheap rubber gloves or nitrile gloves if youre going to to use it. my two cents.
-also one more thought. It may not be neccessary, but if you have larger gaps in the plywood sheets, say 1/2 or larger, i would go to your local hardware store (you could spend hours searching at home depot or lowes), and pick up some "Backer Rod". This stuff is basicaly like foam rope, used to fill gaps in windows and doors and stuff as insulation. It comes in a few different diameters and should be pretty cheap, probably comes in roles of 25 ft or so. I would use this to fill the voids, then seal it up and hold it in place with the foam. It will give some more substance to the seal if the gap is larger.
-karl

[china]

yeah good one. one thing with that foam is that the plastic tube that connects to the can will block realy quite fast with foam. i was making a helmet a few months back and had to pour a little evostick cleaner down the tube and clean and flush the junk out with a wire coathanger. if you not prepard to use the whole can in one go, the foam will set in the top valve of the can and/or the plastic tube and you will have to clean it with acatone or evostick solvent cleaner which will be cheaper and easier to buy in a little can. if you dont seal the top of the can with a piece of plastic(from a plastic bag) and an elastic around the rim at the top of the can, it can compleatly dry out in half a day or less.
so be ready for it,you have to be a bit organised using the foam unless you use it all at once.