Tuesday, April 22, 2008

Bamboo Composites

from WetSand.com - a surfboard company

Bamboo and Composites

Bamboo is planted on the hills in China, rice in the valleys.

Gary Young �..�recalls sitting in a gasoline line during the energy crisis of the mid-1970s when he first got the inspiration to start working with natural materials: "I thought to myself, If what they�re telling us is true, then we need to start making things from renewable resources.� Along the way, it became obvious that you just don�t get any more renewable than bamboo, and it also has the highest strength-to-weight ratio of any natural fiber I�ve ever worked with. I really believe bamboo can contribute to a solution for the planet."

What is bamboo?

Bamboo is a diverse group of plants with over 1,200 varieties of various sizes. Bamboo offers an ecologically viable replacement for wood in many ways. Bamboo is an extremely fast growing grass and has been utilized in building construction in China, India, Indonesia and South America for centuries. Eastern architects and builders design with innovative techniques using bamboo for residential and commercial building, and yet bamboo is relatively new to the Western world.

Usable Bamboo material is available in 3 years compared to wood in 25 years. Mature Bamboo is stronger in tensile strength - superior to mild steel. In compression it withstands up to 52,000 pounds per square inch � stronger than concrete. The fastest species of Bamboo grows vertically2 inches an hour, and some species (moso bamboo) grows three feet a day or a height of 60 feet in three months.

Unlike trees, harvesting bamboo does not kill the bamboo forest, or create soil erosion. A Bamboo forest does not require replanting. Mature Bamboo has an extensive rhizome root system that continues to send up new shoots for decades, so harvesting actually induces the bamboo plant to produce more culms. Bamboo can grow in damaged soil or in areas of degraded lands.

Bamboo used for veneering is primarily Moso, a temperate, running species. It grows mostly in Zhejiang province in the southeast of China - known as the Kingdom of Bamboo. It is harvested when 5 to 7 years old, commonly reaches 90 feet in height and 5� to 6" in diameter. Moso is one of the hardest varieties in the bamboo family.

Bamboo offers a naturally beautiful and environmentally friendly alternative to our limited global supply of timber or wood. In a composite, bamboo veneer can actually be stronger as a substitute for fiberglass.

Bamboo weave mats used on the first two bamboo boards.
Clockwise from lower right: Maverick Burns holds a woven
strip mat before laminating; close up of second weave
pattern, not so tedious to make; the finished mat;
the resulting board. Circa 1996


A composite is a synergistic mixture of different materials bound together that make the combination better than the individual parts. Composites are usually stronger, lighter, more weather-resistant or all of the above. If you are lucky, a composite will be cheaper than what it replaces.

We all have composites in our lives � our highways are concrete reinforced with steel; our homes use plywood or framing made with wood veneer or chips and adhesive; our surfboards, some car bodies and boats are made with fiberglass impregnated with resin; and yes, now bamboo is a fiber in a composite with epoxy, or other plastics, as the adhesive or binder.

Using bamboo in sealed composites elevates bamboo to new levels while reducing the problems of insect infestation, mildew or rotting. Bamboo epoxy composites also eliminate the problems with non-uniformity that are inherent in crooked, tapered, split prone �natural� bamboo.

Bamboo Outrigger Canoe Paddle blade.

Properly done, bamboo is a great looking, strong natural fiber in an epoxy laminate. Think of bamboo as an ecological, lightweight and renewable fiberglass substitute. Safer and healthier too! Probably the biggest hazard from handling bamboo is getting a splinter. (Well, maybe the splinters are healthy - bamboo was used for acupuncture needles in ancient China.)

Bamboo Surfboards by Gary Young have bamboo � epoxy composite skins over hand - shaped foam cores.

BAMBOO IS HEALTHIER for the planet and those who work with it.

Bamboo scraps are bio-degradable; sanding does not produce a skin irritating dust; in processing the laminate produces less fumes.

Bamboo laminates are lighter and stronger - compared to fiberglass. Bamboo epoxy laminates are twice the strength at equal weights.

Bamboo also takes more space in the laminate - saving increasingly expensive oil based materials.

Bamboo floats on water while (fiber) glass does not.

Besides bamboo being safe and economical, it is very fast growing.

Bamboo is among the strongest of natural fibers.

Recently several encouraging process advantages have been developed that increase durability and reduce production times of bamboo composites.

Several products have shown that a Bamboo Natural Fiber Composite can be performance competitive as well. Surfboards, kite boards, snow boards, canoe paddles, canoe and boat decks and hulls are among them.

Use of bamboo in composites creates the potential for industrial markets for the bamboo grower that may someday be as mainstream as corn or wheat. There is a lot of research to be done - perhaps soon the bamboo composites industry will grow as quickly as bamboo itself.

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