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Re: Elevated Bridge B/C
Posted: March 29th, 2009, 4:13 pm
by nejanimb
2000 is extremely impressive. Congrats on winning, though I'm sorry you won't be able to take that to nationals.
What were C division bridges like? Were those efficiencies quite as high? I have to imagine not - I definitely think C has harder specs.
Re: Elevated Bridge B/C
Posted: March 29th, 2009, 4:17 pm
by dickyjones
He replied to the wrong thing. The 2186 efficiency was a C division bridge from Valparaiso High School.
I believe Benjamin Franklin got the 2000+ in division B (not going to nats) and Thomas Jefferson was a little below (going to nats).
Re: Elevated Bridge B/C
Posted: March 29th, 2009, 4:57 pm
by andrewwski
Wow...2186 in C? Impressive!
Re: Elevated Bridge B/C
Posted: March 29th, 2009, 5:00 pm
by croman74
Wow, over 2000 is incredible. Did you guys use bass or balsa?
Re: Elevated Bridge B/C
Posted: March 29th, 2009, 5:03 pm
by sewforlife
croman74 wrote:I think I'm going to try baking my next bridge. dholdgreve, thank you for that useful info. That definitely changed my views on baking. I was just wondering how many grams would baking knock off of my bridge?
most of the time baking knocks off about 6% or 7% of the weight before
Re: Elevated Bridge B/C
Posted: March 29th, 2009, 5:04 pm
by croman74
sewforlife wrote:croman74 wrote:I think I'm going to try baking my next bridge. dholdgreve, thank you for that useful info. That definitely changed my views on baking. I was just wondering how many grams would baking knock off of my bridge?
most of the time baking knocks off about 6% or 7% of the weight before
Oh, okay. Thanks.
Re: Elevated Bridge B/C
Posted: March 29th, 2009, 8:24 pm
by Bjsong
Can anybody post an average ratio of their or somebody else bridge ratio of how much it could hold to how much the bridge weighed. I'm competing in the state tournament next week and i just want to get a sense of what state bridge scores are like.
Re: Elevated Bridge B/C
Posted: March 29th, 2009, 10:34 pm
by Valpo Towers and Trebs
oh yeah sorry, I'm in C div for those that didn't know
croman74 wrote:Wow, over 2000 is incredible. Did you guys use bass or balsa?
about 10 % of the peices were balsa and the rest was bass
Re: Elevated Bridge B/C
Posted: March 30th, 2009, 7:46 am
by Balsa Man
croman74 wrote:by croman74 on Sun Mar 29, 2009 6:04 pm
sewforlife wrote:
croman74 wrote:
I think I'm going to try baking my next bridge. dholdgreve, thank you for that useful info. That definitely changed my views on baking. I was just wondering how many grams would baking knock off of my bridge?
most of the time baking knocks off about 6% or 7% of the weight before
Oh, okay. Thanks.
Uh, Guys, anybody that is thinking that baking will gain them anything - go back and read. From some very careful research:
a) the effect lasts maybe 15-20 min; i.e., it will not do you ANY good in a competition. The research cited on moisture vs comp strength is meaningless for Sci-O competition, because there is no way to maintain a.....reduced moisture content.
b) if you get much over 140F, you will impact the strength of the glue.
Enough said.
Len Joeris
Fort Collins, CO
Re: Elevated Bridge B/C
Posted: March 30th, 2009, 10:23 am
by dholdgreve
Balsa Man wrote:croman74 wrote:by croman74 on Sun Mar 29, 2009 6:04 pm
sewforlife wrote:
croman74 wrote:
I think I'm going to try baking my next bridge. dholdgreve, thank you for that useful info. That definitely changed my views on baking. I was just wondering how many grams would baking knock off of my bridge?
most of the time baking knocks off about 6% or 7% of the weight before
Oh, okay. Thanks.
Uh, Guys, anybody that is thinking that baking will gain them anything - go back and read. From some very careful research:
a) the effect lasts maybe 15-20 min; i.e., it will not do you ANY good in a competition. The research cited on moisture vs comp strength is meaningless for Sci-O competition, because there is no way to maintain a.....reduced moisture content.
b) if you get much over 140F, you will impact the strength of the glue.
Enough said.
Len Joeris
Fort Collins, CO
Len, in most cases I agree with you... My kids always built their bridges and towers down in our moist, humid basement. When they were done they'd bring them up and weight them... Typically, a 10 gram bridge could fairly easily be dried down to 9.5 or 9.6 grams with a hair dryer, depending on how much humidity was in the basement... Over the course of 4 to 6 hours, it may gain .2 grams back before reaching equilibrium with current humidity conditions, but it never returned to the original weight from the basement... In all likelyhood, it would have gotten lighter without the use of the hair dryer, only it would have taken a little longer as it adjusted from high humidity to the lower ambient humidity.
I'm totally on board with your warning about glue though, and have said the same thing in every post I've made.