Elevated Bridge B/C

[croman74]

Wow, 1000's good. I've only built 2, but my best is 617.

[sr243]

Wow, that is amazing. I built 7 so far and I dunno how many parts of the bridges. My second highest ratio is 650. Before that, I was failing so bad with a 450 ratio bridge. Up to my 5th bridge, my ratio were all below 400. Just amazing that I nearly tripled my ratio from before. It was a lot of work and effort for my last bridges. Still wondering whether wood can be reused.

[croman74]

My first bridge was around 350. My school's scioly starts late, so I haven't been able to build many bridges.
On your question about reusing wood, I'm not sure. You might be able to if the wood isn't split along the side. I don't know for a fact. I say that you should just try it for one bridge and see how it does. You could save a ton of wood if you could reuse it.

[andrewwski]

Wouldn't recommend it. The wood weakens when subject to a load.

[croman74]

Wouldn't recommend it. The wood weakens when subject to a load.

That's true. It's a bummer that it can't stay the same. SOOOOOOOOO much money could be saved.

[nejanimb]

The problem with reusing wood is mostly that it has to be cut out. If you're using CA glue, you definitely can't rip it off and use it again, since the wood wouldn't break well, and you can't really reglue it in the same places since the glue has seeped in already and it won't be able to bond as well a second time. I'm sure testing does weaken the wood a bit, but what I've found is that when you build a bridge that holds, it'll usually continue to hold if you test it several more times, indicating that it hasn't weakened too too much in between.

[jazzy009]

Wood+$$$ problem= you should definitely look into any companies near you to try and get a sponsorship. Look specifically for companies that deal with engineering. They love to shell out money for science olympiad. I hate when I have to buy all the supplies for building events...it takes quite a toll on my wallet after numerous experiments

[WrightStuffMonster]

Wood+$$$ problem= you should definitely look into any companies near you to try and get a sponsorship. Look specifically for companies that deal with engineering. They love to shell out money for science olympiad. I hate when I have to buy all the supplies for building events...it takes quite a toll on my wallet after numerous experiments

Building events can be as cheap or as expensive as you want to make them. Wood for bridges though does not have to be very expensive at all as long as you know how to strip your own pieces of larger sheets. $20 worth of wood, if selected intelligently (go through it with a scale and a flashlight to check density, stiffness, and grain), could make several bridges. If you live in the middle of no where (Eagle River Alaska for example) then you will invariably spend more money as you will probably be forced to order online which is expensive because you always have to order about 1000% more than you need as most of the wood they send you will be unusable anyway.

[dudeincolorado]

I'm having the same problem with cost. My partner is determined to use power tools and wood glue. We have gone through at least 30 sticks of balsa because of it. Sigh I'm having event issues...

[WrightStuffMonster]

I'm having the same problem with cost. My partner is determined to use power tools and wood glue. We have gone through at least 30 sticks of balsa because of it. Sigh I'm having event issues...

Unless you are using oak or really dense thick basswood there is no reason to be using power tools. It just wastes wood. The only powertool that might actually be useful here is a high quality table saw if you were trying to cut your own sheets of balsa which I dont really recommend (I have tried it...) Sharp razors that are replaced often are your friend when working with balsa. What power tools are you using now and how are you using them?