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Re: Is this a bad idea?
By:Paul G. Jacobson
Date: 4/9/2001, 8:54 pm
In Response To: Is this a bad idea? (sage)

If your strips are too stiff to bend easily when they are dry then you seem to have found a cure by getting them wet.

Is this good? Probably. The important thing is that it works for you and that it is a repeatable process with consistent results.

The cells of plants have cell walls made of cellulose. Cellulose is a natural plastic which is the basis for products like cellophane. In the natural, unprocessed state, the cell walls are somewhat flexible and permit water to pass through (osmosis). Green, growing, wood is very flxible, but as the cells die the cell walls stiffen. They can be softened a bit by water, but the amount varies by species of plant. Some plants, like cane, rattan, rush, and bamboo become as flexible as rope when they are thin and wet, and they are woven into products. Some species of wood react in this manner, too.

There is a much greater softening effect which comes from heat. When the cells are heated to the proper temperature and the wood is flexed the dead, empty, tree cells will collapse under the pressure of the bending. Think of it this way: when you bend a piece of wood, the inside of the bend compresses, but the outside of the bend does not stretch out any. This heated wood is frequently harder when it cools. From the days of cavemen people used to harden the tips of sticks in their fires to make better spears. Now we kiln dry (or bake) wood to make it stronger.

Some people have found that they get their wood to bend for them by applying dry heat. Others use steam (wet heat). In these cases it is most likely the heat that is helping the wood bend, and the moisture merely transfers the heat more efficiently, and heats the wood evenly and deeply. Once your wood is wet you might try adding heat to the area you want to bend. Try using a clothes iron set to the highest temperature. This should be most efficient if used on the inside of the bend, but it works about as well on the outside as steam that is generated will travel into the wood -- and the strips are not that thick.

Three is no absolute limit on how long you can soak a piece of wood, or wrap it in a damp towel, but you want to avoid leaving the wood wet for so long that it starts to rot or mildew. Soaking for over two weeks is probably not a good idea. Soaking for a weekend is probably fine. That towel can start growing mildew on it, too, so wash it and dry it thoroughly when you can.

hope this helps

PGJ

Messages In This Thread

Is this a bad idea?
sage -- 4/8/2001, 10:04 pm
Re: Is this a bad idea?
Paul G. Jacobson -- 4/9/2001, 8:54 pm
It worked!! I am back on the forms!
sage -- 4/10/2001, 10:01 am
Congratulations. Keep up the good work. *NM*
Paul G. Jacobson -- 4/10/2001, 10:24 pm