plywood

Bamboo Plywood: Review

Bamboo plywood is a product that has existed in Asia for more than a decade.
People outside of large bamboo areas are not accustomed to using bamboo as a
traditional plywood replacement. However, researchers in both India and China have
discovered several different combinations of bamboo that produce strong, durable
sheets of plywood.

In India, researchers have taken a traditional method of working with bamboo and
have adapted it for commercial production. Traditionally very thin bamboo strips
were woven together into bamboo mats. These mats were use in a multitude of
functions in and around the home as well as out in the fields. Researchers used a
technique similar to those used in making plywood to form a flexible and durable
wood substitute. This wood substitute, made by applying heat, glue and
high-pressure to several sheets at one time, has the useful characteristic of being
able to be molded into many useful shapes. This material can be used to produce
items of varied uses from bowls and plates to roof shingles.

Chinese researchers, working on a design also based on traditional construction
methods, formed a different type of bamboo plywood. This form of plywood, currently
used most often in the production of bamboo flooring and paneling, uses bamboo
slats glued together to form a solid board with the grain of the bamboo flowing in one
direction. Two of the solid boards are used, one on top and one on bottom, with the
grain flowing parallel to each other. The strength of the plywood lies in the core
place between these two sheets. The core is also a bamboo board with slats glued
parallel to each other however, this board is place between the top and bottom board
at a 90 degree angle to both. These three layers are included together under high
temperature and pressure. The core supports both the top and bottom layers
adding stability and strength.

Although both methods expand the use and utility of bamboo, they both have
drawbacks. The Indian form of bamboo plywood is very flexible and unable to be
used for load-bearing or structural purposes. The Indian method also requires a
large amount of the thin mats in order to form the plywood. A larger amount of mats
also requires more of the expensive resin and glues used to bind the mats together.
The Chinese method requires an extreme amount of processing of the bamboo slats
so that when they are fitted together, there is no area between the slats. The
Chinese method is also very labor-intensive.

Recently, a new type of bamboo plywood has been developed which combines the
positive attributes of both types of plywood previously mentioned. The top and
bottom layer consist of the Indian style bamboo mats, bamboo slats woven together.
The inner layer consist of large sheets of minimally processed bamboo strips. The
strips are held together in a fashion similar to bamboo curtains and blinds. Each
layer is back at a 90 degree angle from the previous layer. Thicknesses of five,
seven, or nine sheets provide the bulk and strength necessary to use this material as
a loadbearing material. It also can be used in every fashion that typical plywood is
used. Scientists are now contemplating adding a thin paper or wooden veneerto the
outside layers in order to use it as a more decorative item.

This type of bamboo plywood requires a large amount of bamboo with strong culm
walls. Although the machinery used in producing this plywood is minimal, this
process does require a considerable amount of labor. The top and bottom layers
must be woven by hand. The alternating stacking of sheets is also currently done by
hand. The loading and unloading of the sheets into the high temperature pressure
machine also must be done by hand to ensure quality. Countries with a large
workforce a considerable bamboo resources will be able to capitalize on this new
product. Because of the large amount of manual labor required, this industry
provides a lot of jobs for unskilled workers.