How to build wood tower ?

[HydrogenBond]

This is sort of cheating but uses only the materials available. I would pressure treat my balsa with a glue-water solution. After that dries, the balsa will be super-balsa.

Bending the wood into arches can be done with steam. The trick is to do it slowly and in stages using braces. Bend only a small angle at a time, let it relax, then steam and bend a little more, let it relax, etc. It is sort of liking putting braces on one's teeth; tightened in stages.

A simple triangle based beam could look like a crane boon. You use 4 crane boons to form the outline of a skinny pyramid with your platform below the apex. Most of the compression will be on the inside of the 4 boons. Maybe add some I-beams to double up the inside wood to help out with the compression.

[Turtle]

Originally Posted by HydrogenBond

This is sort of cheating but uses only the materials available. I would pressure treat my balsa with a glue-water solution. After that dries, the balsa will be super-balsa.

Bending the wood into arches can be done with steam. The trick is to do it slowly and in stages using braces. Bend only a small angle at a time, let it relax, then steam and bend a little more, let it relax, etc. It is sort of liking putting braces on one's teeth; tightened in stages.

A simple triangle based beam could look like a crane boon. You use 4 crane boons to form the outline of a skinny pyramid with your platform below the apex. Most of the compression will be on the inside of the 4 boons. Maybe add some I-beams to double up the inside wood to help out with the compression.

Well Hydro, as always you have written an entertaining post with some on-topic words included. If I may be so bold as to offer my comments?

First, pressure treating with anything requires a pressure vessel & compressor which few have at hand. Even given one had one, I have my doubts about using it to infuse glue into wood.

Second, steaming requires a vessel as well. A simpler method is to use thin bendable strips to begin with and glue laminate them together over a form. (called 'glue-lam') .

The last bit I think a drawing would be helpful.

I think an excellent example of a tower to follow that uses arches and trussing is the Eifel Tower.

[ErlyRisa]

I was waiting for some-one to say 'Eiffel' ... but why do what's already been done.

how about an asymetric tower...?

'suspend' everything from one side... like maybe a 'lean tower of eiffel'

how to make a pressurised steam box....

plactic tub... cut large hole into it.
Kettle ... place a pipe over the spout and put it into the box.
Turn on kettle - note: pressure can build up ALOT!!! - make sure you have some other hole to release pressure.

[Boerseun]

Be it a tower or a bridge, whatever you do, avoid boxes in your construction. Wherever you end up with cubes in your construction, you'll have problems. If you end up with a rectangular or square-sided structural cube, rather build it out of two triangles.

I once build a completely functional glider that was 100% edible. It was made out of spaghetti sticks and rice paper, and edible glue. It flew a record distance of about 70 meters, then we cooked it. It had a considerable wingspan of close on 2 meters, and was only structurally sound because there were no boxes included in the design.

Boxes are BAD!

[Turtle]

Originally Posted by Boerseun

Be it a tower or a bridge, whatever you do, avoid boxes in your construction. Wherever you end up with cubes in your construction, you'll have problems. If you end up with a rectangular or square-sided structural cube, rather build it out of two triangles.

Boxes are BAD!

Unless they are torsion boxes...>>> The Torsion Box

[Scrubbrush]

Im in some sort of "science club" and have been building model towers for three years. There are many designs you can try, however we have found the strongest and lightest balsa design of them all. Get some balsa wood, as thick as you want, depending on the sort of weight you want to support. Lighter is better though. Next, cut the peiced in half (from the thin side), flip one over (wood grains in oppposite directions makes it stronger), and glue. Be very sparing with the glue. Get a pin and just dab drops on. now clamp or pin it together so it dries straight. Do this to all of the peices. Make your tower sketch on a piece of wax paper, and attach it to a wood board. Make sure measurements are right. Next, put the peices on the sketch and glue. Again, be very sparing. Then you have your tower.
With our winnign design, we made 2 towers, one small thin one made of triangles and a big one of x's. Put them together, with small on top. Make sure that you leave space in the center to hand the weight. You can probably find pictures online if you cant get a picture in your head. Try soinc.com if you have any problems. There might be suggestions there.