Designs

[Freyssenet]

If I have a good, competitive tower, I would not read into the ambiguity of the rules and leave all my work to the subjectivity of the judgment of the event coordinator... you may be disappointed after all your hard work...

[rjm]

ekcnho: You are flirting with disaster.

The top of the tower above 30 cm. from the test base has to fit through an 8.0 cm diameter round circle. That means that in any plane, the upper part of the tower has to fit completely inside that circle. The way we test this in the competitions where I work, at Michigan Region 12, Michigan State Tournament, and Nationals, we slide a flat piece of Lexan with an 8.0 cm circular hole down over the top of the tower down to the 30.0 cm level. The Lexan plate is about 3/16" thick. We are willing to move it a bit side-to-side as we go down, but we don't tip it around obstacles. The rules don't strictly speak of a cylindrical boundary, but in practice there will be some depth to any testing device. If we can't get your tower to fit through our hole without deliberate tipping and contorting of the tester, you are second tiered.

If you have small bumps and protruding ends but still fit through the hole you may be okay. It depends too much on the judge. Please, please, please, don't ask the judge to make a subjective call and don't try to push so close to the limits that he has to make any kind of interpretation. Make the top of your tower small enough that it will clearly fit the rules. There is no reason whatsoever to build it that close to the limits. Don't get yourself in the second tier.

I coach this event as well. Years ago, I had a student who built his tower 2 mm too short for the National tournament and I didn't catch it. Put us in 56th place in Towers that year. Not quite worth it.

Really, there isn't much reason to have a tower with protruding bits of wood. You should be able to clean that up without compromising your tower. If not, then fix it on your next tower.

Bob Monetza
Grand Haven, MI

[ekcnho]

Thanks Bob and Freyssenet. You both make good sense. We've done some sanding and I think we'll be okay. It's just a school competition at a grade school, and it's our first year doing this. It's been a lot of work and definitely a learning experience. It's not a state level competitive tower by any stretch. I think a state level tower has to be clearly under 10 grams and hold the full 15 and we're at like 33 or something and I'm not positive it will hold the full 15. By squaring the weight, there's really a premium on holding the whole load right?

[jander14indoor]

More like a strong penalty for holding significantly less than the full weight. Do the math, not a lot of change between holding 14.5 and 15 kilos. 210.5 vs 225 in the numerator. Big change between holding 10 and 15 kilos. 100 vs 225 in the numerator.

Note, still no benefit for holding MORE than the full weight.

Jeff Anderson
Livonia, MI

[MrsKingCMS]

thanks!

just answered this in another post by you a second ago

it fits INSIDE the 8cm diameter circle, its an imaginary circle

[lllazar]

Do you guys do 3 or 2 x braces on the base (and if you do chevrons, 2 or 3 of those?).

[Freyssenet]

Do you guys do 3 or 2 x braces on the base (and if you do chevrons, 2 or 3 of those?).

For 1/8 square legs, we are using 3 levels of |V| chevron braces - J

[Freyssenet]

Do you guys do 3 or 2 x braces on the base (and if you do chevrons, 2 or 3 of those?).

For 1/8 square legs, we are using 3 levels of |V| chevron braces - J

- this is for the DIC C tower like yours (I appear as DIV B, here, but I am also helping the High School who are doing the DIV C)

[lllazar]

Are you a coach or a student (just wondering).

And thanks, thats what i was thinking of doing as well.

[VishaalK]

How do you connect the tower shaft to the base when using a four leg base, equally spaced around the tower like in this video. Would one just attach the tower shaft to the horizontal cross brace at the top of the base? In addition, I had a design that that looked like this one

except we braced ours a little differently. Why are there no completely horizontal braces on the tower shaft? In addition, where can I purchase a razor to cleanly cut balsa wood, because it seems I lack the strength to use this one. The razors have a bad habit of snapping when I try to cut through a piece, and then they fly all over the place.