Bathtub boats are small watercraft designed around bathtub

Bathtub

A bath , bathtub , or tub is a large container for holding water in which a person may bathe . Most modern bathtubs are made of acrylic or fiberglass, but alternatives are available in enamel over steel or cast iron, and occasionally waterproof finished wood...

s or close facsimiles and are used in bathtub races

Bathtub racing

Bathtub racing started in Nanaimo, British Columbia and involves the use of a bathtub boat. The idea was conceived to showcase Nanaimo to the world, with the first races beginning with the "Nanaimo to Vancouver Great International World Championship Bathtub Race" in 1967.Frank Ney, Nanaimo's mayor...

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Boat design

Early boats were whimsical and crafted from a variety of materials. Today, most bathtub boats are monohull planers with outboard motors. The rules restrict the engine to 8 hp (6 kW), and the weight to a minimum of 350 lb (159 kg) including driver. There are three classes of bathtub boats: stock, modified, and Super-Modified. A form resembling a roll-top tub must be an integral part of the structure. Most tubbers make their "tub" by using a bathtub as the mold to lay down fiberglass

Fiberglass

Glass fiber is a material consisting of numerous extremely fine fibers of glass.Glassmakers throughout history have experimented with glass fibers, but mass manufacture of glass fiber was only made possible with the invention of finer machine tooling...

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Stock must be a stock engine but can be tuned by adjusting the timing. Modified can only modify the lower leg and propeller, and SuperModified can modify the entire engine as long as factory parts are used.