Thanks for the quick response. Will order 1.1, I guess. Recommendations on the 1/16x1/16?Crtomir wrote:I think you would probably want to start with 1/8" x 1/8" x 36" sticks for your columns (legs) that weigh 1.2g and then start dropping down to 1.0g once you get the bracing figured out. To calculate the density, you do this:MadCow2357 wrote:MadCow2357 wrote:I've read through the whole forum, looking for density guidelines when buying balsa. I dug up Balsa Man's (may he rest in peace) explanation on why 1/8 legs are more weight-strength efficient than 3/32 and 1/16 legs, and a couple of other gold mines of info as well. But, I have not found any concrete answer to my current issue.
How to explain? First of all, I have decided to go light for the last 2 towers I will build before states. I went on the Specialized Balsa website, and looked at the "Specially Weighed" 1/16 Square Balsa sticks. I was initially preparing to just click a low density option, and hope for the best, when I came across a table of specific densities from 0.2 to 1.2 grams per 36" stick. My issue is, I cannot determine if a certain density of Balsa is suitable for the goal that I am trying to achieve. Maybe 0.2 is way too lightweight and weak, or maybe it is considered a moderately lightweight density (what I want)? I don't know.
Maybe someone can help give me a guideline to which densities of 1/16x1/16 and 1/8x1/8 are considered lightweight, mid range, and heavy. I don't want the balsa to be overly light, and carry barely any weight, nor do I want to have a 20 gram tower that held the full load like last time (990 is a super cruddy score, even for a rookie like me).
I am aiming for a ~8 gram tower that can carry near full load. Even a 10 gram would be fine to get gold at states (RI is not competitive). A link to a picture of my tower:
https://drive.google.com/file/d/1mcqaf0 ... sp=sharing
https://drive.google.com/file/d/10y3tuF ... sp=sharing
https://drive.google.com/file/d/17C4O9A ... sp=sharing
https://drive.google.com/file/d/1ZRe1kL ... sp=sharing
I hope I didn't make this post sound disrespectful in any way. For some weird reason, I feel like the wording of this post was a little haughty or demanding, even though I didn't mean it that way. Maybe it's just nothing...
1.2g / [(1/8)*(1/8)*(36)] = 2.1 g/in^3
To change this to lb/ft^3, multiply by 3.81 to get 2.1 g/in^3 * 3.81 = 8.13 lb/ft^3
That falls in the "Light Balsa" category (6-10 lb/ft^3) for Specialized Balsa. However, last time I ordered from them, they had run out of wood in that category. Maybe they have more now, I don't know. My guess is between the CA wildfires destroying balsa trees and the uptick in Science Olympiad orders, they might be out of stock. That was a month or so ago.
Hope this helps.
Btw, do you have any opinions on my design, besides it being rectangular base?