Boomilever B/C

[MadCow2357]

By vertical bracing, I assume they mean bracings that connect the main tensions and main compressions; try going for 1/8 x 1/16 or 1/8 x 3/32 instead of 1/16 x 1/16.

Effective arrangement of 1/16 x 1/16 will cut weight and should yield equal if not better results, it really all depends on the arrangement of the vertical bracings.

1/16 x 1/16, under both tension and compression, can support minimal weight. 1/8 x 1/16 or even 1/4 x 1/16 balsa under tension would be far more optimal.

^
1/4 by 1/16 seems a bit overkill tho.

[sciolyperson1]

Effective arrangement of 1/16 x 1/16 will cut weight and should yield equal if not better results, it really all depends on the arrangement of the vertical bracings.

1/16 x 1/16, under both tension and compression, can support minimal weight. 1/8 x 1/16 or even 1/4 x 1/16 balsa under tension would be far more optimal.

^
1/4 by 1/16 seems a bit overkill tho.

The bonus is a thing so you need to make it overkill

[Soumil]

Im having trouble with my compression strands... what size would be the best for a good efficiency

[sciolyperson1]

Im having trouble with my compression strands... what size would be the best for a good efficiency

Compression beam sizes differ by what design you use - so what design are you using?

If you were to use a tower chimney design, 1/8 by 1/8 would be optimal. You could also consider using 5/32 by 5/32.

If you were to use a double beam design or something similar, 1/8 x 3/8 or a similar beam would be optimal.

A main part of scioly is to test and experiment with materials you have, so try different sizes, masses, designs yourself to see what would be the best.

[MadCow2357]

Im having trouble with my compression strands... what size would be the best for a good efficiency

Compression beam sizes differ by what design you use - so what design are you using?

If you were to use a tower chimney design, 1/8 by 1/8 would be optimal. You could also consider using 5/32 by 5/32.

If you were to use a double beam design or something similar, 1/8 x 3/8 or a similar beam would be optimal.

A main part of scioly is to test and experiment with materials you have, so try different sizes, masses, designs yourself to see what would be the best.

I may be wrong, but I think Soumil means the bracing on the compression members when saying "compression strands". Soumil, people generally either use 1/16" square or 1/16" by 1/32" for bracing.

[Soumil]

I'm not sure what the name of the boomilever type im using but it's a tension boomilever one of the most common designs. Also I meant the compression beams not the bracing. I just tested a boomi that used a 1/8 by 1/4 balsa wood for the compression beams however the results weren't too good. My boom is similar to the shape of the blue and red diagram depicted on the website (tension boomilver). Im not sure if im making some simple mistake..please list if you have any tips or suggestions. Also for the bracing I use an x-shaped design is there any bracing that is better and also im not sure if I should use flats for the bracing at the top of the compression portion of the boomi or use square shaped wood to connect in between the compression beams?

[MadCow2357]

I'm not sure what the name of the boomilever type im using but it's a tension boomilever one of the most common designs. Also I meant the compression beams not the bracing. I just tested a boomi that used a 1/8 by 1/4 balsa wood for the compression beams however the results weren't too good. My boom is similar to the shape of the blue and red diagram depicted on the website (tension boomilver). Im not sure if im making some simple mistake..please list if you have any tips or suggestions. Also for the bracing I use an x-shaped design is there any bracing that is better and also im not sure if I should use flats for the bracing at the top of the compression portion of the boomi or use square shaped wood to connect in between the compression beams?

Lol so you meant the compression beams - see sciolyperson1's post above then.
When possible, use lap joints for bracing (members glued on top which allows for better connection), not butt joints (connecting in between.

[LoneMonkey]

Is not going for the bonus even worth considering? I'm new to boomilever but I'm a really big fan of lighter, simpler designs. I feel like it would be more consistent and less risky, especially considering I almost certainly won't make my school's states team and will mostly be going to lower-level invitationals where everyone will probably be scoring lower anyway.

[RobertYL]

Is not going for the bonus even worth considering? I'm new to boomilever but I'm a really big fan of lighter, simpler designs. I feel like it would be more consistent and less risky, especially considering I almost certainly won't make my school's states team and will mostly be going to lower-level invitationals where everyone will probably be scoring lower anyway.

I believe the main priority this year should be getting the bonus. The extra 5kg increases your efficiency by 33% compared to your actual efficiency (assuming it breaks at 15kg). Therefore, only booms that are extremely overbuilt to hold over 20kg are disadvantaged by the bonus (but they have their own problems and could lower their weight).

Regarding consistency, I would argue the reverse. Heavier, stable designs are a lot more consistent than lighter designs. Lighter designs are more prone to the natural variance in the wood. And heavier designs will most likely have a maximum capacity of 17-19kg (if it's built right) so any confounding variables during competition still allow for it to hold all the weight. I personally stress test all my booms before competitions (to 5kg or all the way up to 12-13kg) in order to make sure there aren't any major weak points or glaring issues. I haven't had any issues with weakening wood or glue because of it as long as no cracks or fractures form during the testing.

[Lorant]

Is not going for the bonus even worth considering? I'm new to boomilever but I'm a really big fan of lighter, simpler designs. I feel like it would be more consistent and less risky, especially considering I almost certainly won't make my school's states team and will mostly be going to lower-level invitationals where everyone will probably be scoring lower anyway.

I believe the main priority this year should be getting the bonus. The extra 5kg increases your efficiency by 33% compared to your actual efficiency (assuming it breaks at 15kg). Therefore, only booms that are extremely overbuilt to hold over 20kg are disadvantaged by the bonus (but they have their own problems and could lower their weight).

Regarding consistency, I would argue the reverse. Heavier, stable designs are a lot more consistent than lighter designs. Lighter designs are more prone to the natural variance in the wood. And heavier designs will most likely have a maximum capacity of 17-19kg (if it's built right) so any confounding variables during competition still allow for it to hold all the weight. I personally stress test all my booms before competitions (to 5kg or all the way up to 12-13kg) in order to make sure there aren't any major weak points or glaring issues. I haven't had any issues with weakening wood or glue because of it as long as no cracks or fractures form during the testing.

I agree, it takes inhuman consistency to build very lightweight designs. Also, to ensure consistent competitiveness (>2000pts) you would have to build boomis under 5 grams (rough estimate assuming you plan to hold 10kg) which give this year's construction parameters is absurdly difficult. It's much simpler to go for an 8-10g boomi, holding full weight+bonus to achieve a score between 2000 and 2500, scores which should secure you a fair placement most places.