General Discussion

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mrsteven
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Re: General Discussion

Post by mrsteven » February 10th, 2012, 8:35 pm

questionguy wrote:Does the 70 cm include the base of the tower?
ya. 70cm is from bottom of tower to top
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Re: General Discussion

Post by Vizard007 » February 10th, 2012, 9:09 pm

Well, we tried using a jig, but it still ended up crooked. :( I think it's because the actual wood itself is curved if I were to lay it on a flat surface. Is there a solution to this? Thanks so much for your help by the way!
It's so easy, even a Badger could do it.

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Re: General Discussion

Post by jander14indoor » February 11th, 2012, 4:54 am

Two choices on curved wood I can think of.

Throw out the crooked pieces (better, don't buy them to start with). Good wood is critical in this event, don't saddle yourself with a handicap before you even start building.

Use the curves in equal and opposite directions so they offset each other and end up straight. This might even be useful in building in some preloads to force your structure to behave in certain ways as it is loaded, but that's a little tricky.

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Re: General Discussion

Post by Vizard007 » February 11th, 2012, 8:09 am

jander14indoor wrote:Two choices on curved wood I can think of.

Throw out the crooked pieces (better, don't buy them to start with). Good wood is critical in this event, don't saddle yourself with a handicap before you even start building.

Use the curves in equal and opposite directions so they offset each other and end up straight. This might even be useful in building in some preloads to force your structure to behave in certain ways as it is loaded, but that's a little tricky.

Jeff Anderson
Livonia, MI
Oh, I see. Thank you so much! :) Also, I was wondering, what type of balsa grain are you guys using? Do you think it'd make a difference?
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Re: General Discussion

Post by fanjiatian » February 11th, 2012, 2:46 pm

Do any of you have tips for steadying the bucket?

I find it extremely difficult to steady the bucket without having shaky hands.

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Re: General Discussion

Post by lucwilder42 » February 11th, 2012, 10:36 pm

fanjiatian wrote:Do any of you have tips for steadying the bucket?

I find it extremely difficult to steady the bucket without having shaky hands.
Have your partner do it. A shaky bucket can wreck a perfectly good tower very quickly
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Re: General Discussion

Post by fanjiatian » February 12th, 2012, 5:52 am

Good idea.
Where is the best place for your hands to go?
Near the bottom or top of the bucket?

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Re: General Discussion

Post by thsom » February 12th, 2012, 7:23 am

Hey guys, I just tested a tower and it held merely 2.57 kg :oops: . However, when I tested the base and chimney at home, both held over 15 kg. The tower broke at the connection. No wood actually snapped causing it to break, the chimney just literally quickly fell of of the base. Was it because of a small lean and improper/inadequate connection of the two because if I can fix this issue, I could have a nice tower.

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Re: General Discussion

Post by foreverphysics » February 13th, 2012, 6:44 am

fanjiatian wrote:Good idea.
Where is the best place for your hands to go?
Near the bottom or top of the bucket?
Neither. Don't actually touch the bucket. Give it about a .5 cm margin to swing. Put your hands on either side of the bucket nearer the center, but again, don't touch the bucket. You can put more pressure on the bucket if you're not careful, and also, the more sand you dump in the bucket, the more stable it becomes. A large part of it also has to do with how you pour in the sand. I would suggest pouring the sand in a slow, large circle at first, gradually speeding up and centralizing. At the end, you should easily be able to dump full beakers of sand into the center of your bucket with no unbalancing effects.
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Re: General Discussion

Post by Frogger4907 » February 13th, 2012, 7:38 am

thsom wrote:Hey guys, I just tested a tower and it held merely 2.57 kg :oops: . However, when I tested the base and chimney at home, both held over 15 kg. The tower broke at the connection. No wood actually snapped causing it to break, the chimney just literally quickly fell of of the base. Was it because of a small lean and improper/inadequate connection of the two because if I can fix this issue, I could have a nice tower.
Even the slightest lean will really affect the distribution of weight to one side of the tower causing it to snap much quicker. and unlevel testing surface could provide a similar affect.
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