Welcome to Gaia! ::

So I have to build a tower for a competition I'm in.

The goal is to build the most efficient tower.
Efficiency=Weight held/weight of tower

[see the specifications for it here]

So I've come up with a couple of designs so far, and I'd like advice on them or suggestions for new designs if anybody has any.

So here are some of the designs I have so far.


Please excuse the crappy picture sweatdrop

Design 1

Basic, but it works. I designed one with T-beams, and one with plain pieces of balsa wood (I forgot to add that all of these towers are being designed with balsa in mind).
The t-beams were too strong for 15 k, and really heavy. I'm thinking about making another one with much smaller t-beams, and smaller cross-bars.
The plain balsa version sucked. But I think that was my fault. I had the t-beams on the other one with the backside facing outwards. On this, the pieces were flat on it, and so they easily bent, and so it broke at 3 kilos mad

Design 2

The idea was to take weight off of the main beams, and not just have the cross pieces wasted on just holding everything together. Hopefully this would make it more efficient.
I put in the extra cross piece at the bottom because that part of the main beam always has a lot of stress on it, so hopefully that would help hold it in.

Design 3

When I think of efficient towers, I think about the K.I.S.S. rule (Keep It Simple Stupid), and I don't think this design fits in the simple category.

The idea was to make the cross pieces have smaller angles, and give the main struts more support. This could also be done with more pieces attached to the main beams to keep them from bending. Or a cross piece could be put in between the x's to the main beams to reinforce them.



So, any suggestions?

Edit:

Another problem I've been having is how to construct the tower.

If you construct it by trying to hold the skeleton of the tower (main support beams) while the glue dries, you usually accidentally break the glue bond before it dries, or it ends up crooked.

If you try constructing two sides and connectings them, the main support beams don't face away from the tower, and so they bend and break really easily.

I've been using gorilla glue, and that requires a lot of time to dry. Super glue is evil. You can make it work, but if you break the bond before it dries, you have to sand paper all of the dried glue off before you can try again. You also get too much on your hands
gonk

1,000 efficiency?.. surprised

My max so far is 650


What about the efficiency of #2?

And by 'middle block' do you mean the triangle supports?

And the balsa core of the main supports with the bass layer on top. Should the balsa part be thick with a thin layer of bass?

Also, does it matter very much if the shape of the tower is trianglular or square? I think it would be harder to construct a triangle, and I'd rather just use a square if possible.

Okay, thanks.

Another thing I was wondering about was the quality of balsa. At places like Hobby Lobby, they have cheap balsa, that's really light. At small hobby shops they have 'high quality' balsa that's heavier, and should be stronger (To Plopper: If you remember Art Coup, that's where I'd get it).

Which one do you think is better?


One more thing I was wondering about. How to actually construct a basic tower.
I've made one by making one side at a time on a piece of styrofoam. To hold it down, I used needles, and I just set a small amount of glue on the joints.
The other way was to just make the skeleton (the main supports, the top, and bottom) of the tower, and add in the cross pieces from there.

Neither way has worked too well. The first way makes the main struts angled weird, and the second way requires super glue or tape. Both are evil.

So any suggestions about that?

Hobby Lobby only has crappy balsa. Really crappy stressed
Some pieces had holes cut all the way through them.
I think I'm just going to use high quality from Art Coup.

No no, it's not coming out bent up. The problem was that I was using flatter pieces of wood, not square ones. The flat ones had to face outwards, or they bend really easily when weight is applied. I'm going to use the pin method with square pieces now, and see if it works.

Yeah, that stuff would be better for planes. But how does it not bend all over? The main body of the plane is usually one piece of wood. Even at the size it was at it was really weak.

Oh
I never did a plane, so I thought it was one piece of wood. That makes more sense.

It's not really a resolvable topic until the competition is over. I'm just looking for advice about the tower.

It gives people the option of helping if they want to. And no, you haven't. Unless you want to list out all of the millions of designs and details with them possible, you haven't covered it.

You can give one opinion on this stuff. Yours. I want multiple view points.

I'm not waiting until the last minute, even if I had not posted this, I would still be trying things. This is just for more ideas with things.