(The Nuances of) Measuring Buckling Strength with SFPD

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Re: (The Nuances of) Measuring Buckling Strength with SFPD

Post by MadCow2357 »

As a guideline, how much buckling strength does 1.2g 1/8"*1/8" and 0.3g 1/8"*1/8" have. I measured 12" 1/8" piece at around 300g. Is that normal?
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Re: (The Nuances of) Measuring Buckling Strength with SFPD

Post by dholdgreve »

MadCow2357 wrote:As a guideline, how much buckling strength does 1.2g 1/8"*1/8" and 0.3g 1/8"*1/8" have. I measured 12" 1/8" piece at around 300g. Is that normal?
If you can get .3 gram 12" sticks that test at 300 grams you should be in pretty good shape. Most will test in the 180 to 240 gram range. The highest .3 gram 12" sticks we have found tested 390.
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Re: (The Nuances of) Measuring Buckling Strength with SFPD

Post by MadCow2357 »

You mean 1.2g 1/8 sticks right? Two more questions: What should I aim for while choosing square 1/16? And how will I test the BS of 1/32*1/16 strips?
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Re: (The Nuances of) Measuring Buckling Strength with SFPD

Post by MadCow2357 »

Oh ok I see what you mean. Disregard the first question in my last post.
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Re: (The Nuances of) Measuring Buckling Strength with SFPD

Post by Cow481 »

anyone have any last tower predictions for top 6 in both div b and c? i am estimating 3200-3600
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Re: (The Nuances of) Measuring Buckling Strength with SFPD

Post by MadCow2357 »

I just started a new thread for score predictions Cow481... I'm guessing that people will not look in this thread for score predictions.
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Re: (The Nuances of) Measuring Buckling Strength with SFPD

Post by MadCow2357 »

So far I have been only testing my 1/8"*1/8" balsa pieces with SFPD. Should I also test square 3/32 and square 1/16 pieces in the same way?

I also recently ordered 1/32" sheets Can I test the buckling strengths of those also?

Sorry if I have repeated myself over and over.
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Re: (The Nuances of) Measuring Buckling Strength with SFPD

Post by dholdgreve »

MadCow2357 wrote:So far I have been only testing my 1/8"*1/8" balsa pieces with SFPD. Should I also test square 3/32 and square 1/16 pieces in the same way?

I also recently ordered 1/32" sheets Can I test the buckling strengths of those also?

Sorry if I have repeated myself over and over.
1/32" thick material basically will have no buckling strength to speak of, unless the pieces are reduced to 1 cm in length, serving no purpose in towers.
1/16" will have very little buckling strength unless the pieces are sub 3 cm.
Yes, you could reduce your columns to higher density 3/32" material, but I think you will find that a higher density 3/32" column compared to a 1/8" lighter density column, with both weighing the same, will not perform as well due to the cross section of the piece. This being said, the convex also applies... Find a piece of 5/32" light density and compare it to a 1/8" medium density piece weighing the same. In 9 out of 10 cases, I believe you will find that the 5/32" will outperform thinner pieces weighing the same.

But this is only half the battle. As you go lighter with the columns, the bracing is more likely to pull a section of light weight columns out where glued. Find the point where you can go as light as possible with the columns while still having enough substance to hold the glue joint.
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