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Concrete Boat!

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Picture of Concrete Boat!
silicone spray.jpg
concrete making.jpg
Concrete Boat:

Materials List- 
Concrete
Water
Rubber Gloves
Silicone Spray
Boat shaped mold (I used a Tupperware bowl but almost anything can be used) 
Bucket to mix concrete in

Step 1: 
First create a mold of the shaped boat you want. My mold was a medium sized plastic Tupperware bowl, but you could create one out of wood, Styrofoam or anything else.
Step 2: 
Coat the mold with silicone spray so that the concrete will not stick to it.
Step 3: 
Put the concrete in the bowl and smooth it out with your hands until it is distributed evenly. 
Step 4: 
Let the concrete dry for at least 24 hours and then remove it from the mold. Now let it float! (: 
Mix the appropriate amount of concrete and water together, make sure to wear rubber gloves! 
dchrenek11 months ago
a good idea is to also use the next smaller bowl in the tupperware set if you are looking for a mold like finish. just fill the first one 3/4 full and shove the second inside. weight it down
Looks cool. I made a bowl in a similar way, but tried to pour the concrete in. It was very tricky. And I see you wearing gloves!... I learnt the hard way :(
http://www.instructables.com/id/Smash-and-Grab-BowlCast-Concrete-Glass/
See also
http://www.asce.org/concretecanoe/

Rowboats were actually one of the first things built (and sold) by the guy who invented steel reinforced concrete back in 1848 or so http://en.wikipedia.org/wiki/Concrete_ship
I am told that during WWII that concrete was used to make ships, because steel was so scarce. After the war, most of them were sunk to act as reefs. Fishing has always been good there.
wat yore talking abowt is "pykreet" (apologis for spelling - im dislexic) mythbusters, did a thing abowt it not so long ago - try youtube they didnt actchaly make boats i dont think but it was tryed
You're mistaken about what pycrete is. Pycrete is a composite of sawdust or wood fiber with ice. Here is a link to Wikipedia's article on Pycrete: http://en.wikipedia.org/wiki/Pykrete

Ships were made of concrete, and some boats still are (I don't think anyone is currently making big ships from concrete).

There were also proposals to build various things, including floating docks and perhaps ships from pycrete.
Nice Grammar.

And they did actually get it to float.
cheers! my grammar is ushally like pin the tale on the donky - if its in the rite plase its a happy coinsedents!
http://www.concreteships.org/ships/ww2/
cammers2 years ago
I found this concrete ship in China recently. The river has apparently been reclaimed around it and it's now part of the landscape. .

Concrete yachts are pretty common. Usually known as "ferro" boats. A famous concrete racing yacht was/is "Helsal II".
helsal ii.jpgconcrete ship.jpgconcrete ship.jpg
danzo3212 years ago
They did make concrete ships, but steel reinforcing is a big part of them. Supposed to be extra desirable in rocky water. Look it up.
Looking into cement boats is cool....

You can use wooden molds, and the release agent on that is oil - but on a small boat mold, I suppose that a good sanding of the mold, and a coating of vaseline would be fine.... or layering of urethane paint or food wrap.

And you can look at reinforcement.

Positive or male molds are good to work with as well.

That way you can use a wire probe to get an accurate thickness and you can have a crack at making a boat with sails etc...

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