Towers B/C

[shrewdPanther46]

at that thickness they get very flexible. Plus, idk how light you can get building with that strategy which would really limit efficiency.

[Cow481]

Not sure if this has been asked already, but is there any benefit to adding a single horizontal brace on each side where the base meets the chimney?

There would be a benefit if you put the brace inside the tower (butt joint) and put a small peice of wood going up the leg where the two parts meet (around 1/8 x 1/16 or 1/32)

[dholdgreve]

I have been thinking about this for a while, but just wanted to hear your thoughts about it.

What if someone mad e a coverall tower, which is basically a tower without any crossections, but rather 1/32 or 1/64 sheets covering all sides of the tower (using lightest density).
Would this work?

I too have considered this... We have all discussed at great lengths the pros and cons of X braces... Z braces... Ladders... now enters yet another type of bracing known as diaphragm bracing, where each wall is sheeted solid. With X or Z braces, you are supporting the columns only at the joints where the bracing connects with the column, leaving the area between the bracing as "unsupported." The fewer the tiers of bracing, the greater the unsupported length between "nodes." ( a node is what they call the bracing to column joint.) The longer this unsupported column length is, the more the builder must compensate for by increasing the density, cross section, and bending strength of the column. Conversely, with a diaphragm type bracing system, the columns are continuously supported by the edges of the diaphragms. Theoretically, this should mean that the columns could be reduced to next to nothing... maybe 1/16" square to make up for the obvious increase in material elsewhere.

Diaphragm bracing is used in construction in several instances... It is used in shear walls designed to withstand huge wind loads. Roof sheeting is also designed as diaphragm bracing If you've ever noticed, roof sheeting is nearly always installed with staggered end joints... now you know why...

I've even thought about the possibility of installing diaphragm bracing on the sides of a tower, then carefully cutting away large sections within, to lighten the finished product... the problem is, that the grain would be running the wrong direction for this, allowing it to split or tear apart at the slightest load!

Now, if they ever change the rules to allow pulp products such as paper to be an acceptable material, I believe this is a real possibility as it is as strong one way as it is the other, but until then, I don't believe you would be able to get the weight down as much as would be needed to be really competitive.

[kinghong1970]

time to get some japanese hand planes?

https://www.youtube.com/watch?v=kFLt0duNrgc

hahaha

now don't get angry at me for having you guys gawking at the video for 1:27 like i did...

oh and here's another one for a slow monday morning...

https://www.youtube.com/watch?v=zs9X-XzFGHI

fun starts at 2:15

[DarthBuilder]

I’ve read about baking a tower on past discussions. I couldn’t find the percentage, but how much percent would baking the tower decrease from?

[Raleway]

I’ve read about baking a tower on past discussions. I couldn’t find the percentage, but how much percent would baking the tower decrease from?

Baking a tower can decrease the weight of a tower from 1-10%, depending on how brave you are, and how much your tower weighs at the beginning. However, once the tower is exposed to room temperature and cools down, it gains back all of its weight. This can occur in the span of seconds or minutes. Furthermore, baking your tower exposes the glue to various other forces it might not have been built for, and same goes for the wood. I have only seen baking work once (the team used a special box and brought out the tower very, very quickly and prayed the weight would stabilize for a split second. Baking is temporary but also very dangerous. Use it as you will and good luck!

[Balsa Man]

I’ve read about baking a tower on past discussions. I couldn’t find the percentage, but how much percent would baking the tower decrease from?

Baking a tower can decrease the weight of a tower from 1-10%, depending on how brave you are, and how much your tower weighs at the beginning. However, once the tower is exposed to room temperature and cools down, it gains back all of its weight. This can occur in the span of seconds or minutes. Furthermore, baking your tower exposes the glue to various other forces it might not have been built for, and same goes for the wood. I have only seen baking work once (the team used a special box and brought out the tower very, very quickly and prayed the weight would stabilize for a split second. Baking is temporary but also very dangerous. Use it as you will and good luck!

Yup! To add a couple thoughts from some testing a number of years ago (put pieces of 1/8x1/8 of varying density in the oven, then put onto a scale and recorded weight vs time as they returned to pre-baked weight. Low density returned to 90% of pre-bake weight within a bit less than 1 minute. High density (~3x density of low density piece) took a bit less than 2 min. The magnitude of weight reduction depends on relative humidity. On a dry day (relative humidity below 20%) only a few percent weight loss; on a humid day (relative humidity 90%+) approaching 10% (actual highest seen about 8.5% as I recall. So, if you have a rainy, wet day the day of competition, and the check-in process is being run so you can get the tower from sealed box to the scale quickly, you have a chance of picking up a couple of tenths of a gram.

One option is oven baking- 140 degrees F is maximum I've ever used In for about 10 min). To hold the moisture loss, needs to go immediately into a sealed box with silica gel. The other is using (CAREFULLY) a hair dryer at the competition - tower in a big plastic tub; one hand in the tub, close to the tower to feel the heat the tower is seeing to avoid getting it too hot.

[dholdgreve]

This used to be a thing years ago for bridges... The first time I ever saw a tie in an SO structural competition... It was at the Ohio State competition, 2 bridges weighed exactly the same to the 1/100th of a gram. Both carried the required load of 15,000 grams. both ended with the same score!... Tied for first place!... until they reweighed both bridges after testing. One had been dried down by a hair dryer just prior to check in, the other had not. The one that had been dried, gained .03 grams and was awarded the silver medal.

[DarthBuilder]

Thanks everyone for the input! That’s very cool and kinda funny at the same time. If I actually do this method of baking a tower, how many silica gel packets do I put inside the box?

[Unome]

This used to be a thing years ago for bridges... The first time I ever saw a tie in an SO structural competition... It was at the Ohio State competition, 2 bridges weighed exactly the same to the 1/100th of a gram. Both carried the required load of 15,000 grams. both ended with the same score!... Tied for first place!... until they reweighed both bridges after testing. One had been dried down by a hair dryer just prior to check in, the other had not. The one that had been dried, gained .03 grams and was awarded the silver medal.

Reminds me of that one time there was a tie for a medaling place at Nationals in Towers... I guess that's part of why they added more tiebreakers.