PICTURES, SCORES, VIDEOS!!!

[sciolycats]

Does anyone have any basic design tips? I'm using bracing type P1 from the Wikipedia, consistently getting scores of ~1400 but, of course, I would like to be around 2,000. 3 sets on the top half and 3 on the bottom half.

Double the bracing and reduce the column weight.

By column weight, do you mean the thicker, usually 1/8x1/8 structural pieces? If so, how do you suggest reducing the column weight? (shortening the columns is not an option because of the height minimum)

[dholdgreve]

Does anyone have any basic design tips? I'm using bracing type P1 from the Wikipedia, consistently getting scores of ~1400 but, of course, I would like to be around 2,000. 3 sets on the top half and 3 on the bottom half.

Double the bracing and reduce the column weight.

By column weight, do you mean the thicker, usually 1/8x1/8 structural pieces? If so, how do you suggest reducing the column weight? (shortening the columns is not an option because of the height minimum)

We've bought 1/8" x 1/8" balsa in both 36" and 48" lengths. The first thing we do when an order comes in is to cut the balsa into 12" lengths... We can do this, because we are Div B, and both top and bottom columns can be created from 12" blanks. We then go through and weigh each piece and sort them. 12" balsa blanks can weigh anywhere from .19 grams to well over 3 grams each. Same size, different weights. Next, we will determine the general weight of the columns we want to use, then do the Single Finger Push Down test on each piece. We don't do the SFPD test until the stock is cut into 12" blocks because we want the results to be specific to that piece of material... not the 2 or 3 adjacent pieces. If you find pieces that have a SFPD of 300 grams, you may be able to design a tower with only 3 or 4 tiers of bracing. If you find pieces that have a SFPD test of 200 grams, you may want to up to 8 tiers of bracing. Logically, as you add tiers of bracing, the distance between connections (nodes) is reduced. The more bracing tiers, the less "unsupported column length" there is between nodes.

The whole trick to this competition is to find the most efficient combination of column density and the number of tiers of bracing it takes to support them. This takes hours and hours of testing, and several dozen towers built with very carefully documented material used and results. Sure... you might get lucky... but can you repeat it?

[emilyshangg]

Hey, I saw a few people talk about a formula that can calculate your score that Balsa Man (may he rest in peace) posted or mentioned? I've gone through the forum and can't seem to find it...
Thanks!

[StormTJ]

Any predictions for a placing score at nationals in division C?

[jinhusong]

Hey, I saw a few people talk about a formula that can calculate your score that Balsa Man (may he rest in peace) posted or mentioned? I've gone through the forum and can't seem to find it...
Thanks!

The score is simple, just the (weight the tower can hold + bonus if any) / weight of tower.

Maybe you are talking about the spreadsheet about leg strength and intervals for all X bracing?

[jinhusong]

Maybe this?

https://docs.google.com/spreadsheets/d/ ... edit#gid=0

[emilyshangg]

Maybe this?

https://docs.google.com/spreadsheets/d/ ... edit#gid=0

Yes, that's exactly what I was looking for. Thank you so much!

[jinhusong]

Maybe this?

https://docs.google.com/spreadsheets/d/ ... edit#gid=0

Yes, that's exactly what I was looking for. Thank you so much!

Just as a reference, my son and his partner built a square based bonus tower:
Base: strong leg, BS ~48 at 36 inch with 5 interval, all X bracing (bottom 2: 3/32X1/32 strips from 10g sheet, next 2 1/16X1/32 strips from 8g sheet, top one 1/16X1/32 from 6g sheet. The sheet is 1/32X3X36).

Chimney: light leg, BS ~20 at 36 inch with 9 interval, all X bracing ( 1/16X1/32 strip from 6g sheet)

Total weight 8.06g, holding 13kg, got first place in Northern California State. I was not there, but my son told me the table was not leveled. It was designed for 15kg.

I thought they may be able to get a medal, but they got first place.

Hope these information can help you.

[JVallurup47]

Does anyone know the winning tower scores from the state tournaments?

[Unome]

Does anyone know the winning tower scores from the state tournaments?

High.

For Missouri specifically, over 2000 should be an easy first or second in either division. Over 1400 should place you in the top 5 pretty easily.