My third boomilever for science olympiad, weight is 6.5 grams. It held 4317 grams, giving it an effeciency score of 664. This time has thinner balsa for the support beams and thicker balsa for the main structure. The failure point was still up towards the base, even though I added some more bracing.
My next boomilever. I added more bracing, and used 1/8 inch by 1/8 inch balsa wood (thicker than used on #1). Yet to be tested, I will update with results.
UPDATE: The boomilever weighs 6 grams, and held 2.5 kilograms, giving it an efficiency score of about 410. It broke where the balsa comes out of the base, it snapped that length of balsa in half. I will sandwich that area with another piece of wood to make it stronger.
Here is my first version of boomilever for this year’s science olympiad. I weighs 9.3 grams, but it only supported 1.5 kilograms giving it an efficiency score of 161 (weight held divided by weight). A good score would be above 1000. The main flaw was that the two sides of the boomilever were not braced together, allowing it to bow out and split. My next design will most likely have more braces. Pictures: