Nice. Essentially correct (I get a slightly different number in the "Proportion" column for 1/7th (0.96 vs your 0.91), which makes makes the number in the "Multiplier" column 109.26 (vs your 120.76) might want to re-check that.hearthstone224 wrote:Hey everyone, I'm going to put the numbers I got out there for verification. The "safe strength" column refers to the strength a stick of 36'' balsa must have to be braced at that certain interval and work out. I want to get this part right once and for all so that I don't need to think about this anymore.
Is there any disagreement? If not I think people can use these numbers.
I think only the colored ones will matter because the sticks usually don't reach 220 g in BS At least I don't have any.
So do you think the main composition will be bracing at 1/5th interval around 80 BS? Because I thought maybe we could be using 1/4th interval with sticks around 130BS or so. They are fairly heavy though.
And just out of curiosity, can we brace at a let's say 1/4.5 interval? I know it sound fairly weird but would that maybe have a positive tradeoff?
Your conclusion that bracing at 1/5 intervals for a stick with a 36" buckling strength testing at 80 gr should hold is correct, and that a stick with a 36" buckling strength of 130gr should hold at 1/4 interval, and that to go to 1/3 interval, you'd need a stick testing at 220gr.
The (1/8 x 1/8 x 36") stick weights you should expect to get those buckling strengths are (from the table I'm having trouble attaching) are:
1/5 interval- 1.5-1.6gr range
1/4 interval- 2.2-2.3gr range
1/3 interval- 3.5-3.6gr range. I'm not surprised you haven't seen any this heavy, it's pretty uncommon/pretty high density. They do exist; in fact, you can order sticks up to 4.7gr from Specialized Balsa . They start to get pricey as you push past 3gr. Bottom line, 1/5 and 1/4 bracing intervals should be achievable with common/typically available balsa.
As to 1/4.5 interval, you end up with the same number of bracing points/ ladders you would have at 1/5 intervals, with top or bottom one being significantly shorter than the others; the leg in that shorter section would be much stronger than needed (inefficient), and the other sections would be longer, requiring heavier leg material than would be needed with 1/5 bracing. By evenly dividing, you minimize the leg strength needed.