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Re: Elevated Bridge B/C

Posted: September 11th, 2009, 1:39 pm
by jazzy009
Max height 20cm
clearance: 30cm long x 12.5 cm high

C

I love this season.

Re: Elevated Bridge B/C

Posted: September 11th, 2009, 2:12 pm
by croman74
T-B wrote:The 2010 guidelines are out. The clearance under the bridge is more than doubled in Division B (15cm x 15cm new vs. 10cm x 10cm old), overall height limit is raised from 15cm to 20cm, and the limitation on individual member cross-section is removed. Same structural efficiency ratio and weight limit (15kg). Let the building begin! :D
Sorry but my math sense is kicking in. That's definitely not more than doubled.
Anyway, I'm definitely looking forward to this year. It seems like they just added height to the bridges. And like mentioned before, what's the span?

Re: Elevated Bridge B/C

Posted: September 11th, 2009, 2:20 pm
by AlphaTauri
Sorry if someone has already posted this, but do you think it's more effective to build an "A-frame" bridge or a regular bridge on legs?

Our team never got around to testing this last year before States. (We were more concerned with building a bridge that would actually hold 15kg after our epic fail at Regionals where the bridge broke at 14.87kg. :? )

Thanks!

Re: Elevated Bridge B/C

Posted: September 11th, 2009, 2:24 pm
by blue cobra
croman74 wrote:
T-B wrote:The 2010 guidelines are out. The clearance under the bridge is more than doubled in Division B (15cm x 15cm new vs. 10cm x 10cm old), overall height limit is raised from 15cm to 20cm, and the limitation on individual member cross-section is removed. Same structural efficiency ratio and weight limit (15kg). Let the building begin! :D
Sorry but my math sense is kicking in. That's definitely not more than doubled.
Anyway, I'm definitely looking forward to this year. It seems like they just added height to the bridges. And like mentioned before, what's the span?
Sorry, but now my math sense is kicking in. Old clearance was 10x10. That's an area of 100 sq. cm. The new clearance is 15x15, which has an area of 225 sq. cm. 225>2(100) :D
I interpreted T-B's post to say that span was the same, but it would be grand if someone with rules clarified.

Re: Elevated Bridge B/C

Posted: September 11th, 2009, 2:31 pm
by croman74
blue cobra wrote:
croman74 wrote:
T-B wrote:The 2010 guidelines are out. The clearance under the bridge is more than doubled in Division B (15cm x 15cm new vs. 10cm x 10cm old), overall height limit is raised from 15cm to 20cm, and the limitation on individual member cross-section is removed. Same structural efficiency ratio and weight limit (15kg). Let the building begin! :D
Sorry but my math sense is kicking in. That's definitely not more than doubled.
Anyway, I'm definitely looking forward to this year. It seems like they just added height to the bridges. And like mentioned before, what's the span?
Sorry, but now my math sense is kicking in. Old clearance was 10x10. That's an area of 100 sq. cm. The new clearance is 15x15, which has an area of 225 sq. cm. 225>2(100) :D
I interpreted T-B's post to say that span was the same, but it would be grand if someone with rules clarified.
ooh, good point.
AlphaTauri wrote:Sorry if someone has already posted this, but do you think it's more effective to build an "A-frame" bridge or a regular bridge on legs?

Our team never got around to testing this last year before States. (We were more concerned with building a bridge that would actually hold 15kg after our epic fail at Regionals where the bridge broke at 14.87kg. :? )

Thanks!
For that, definitely go to the archived thread of EB and search A-frame. there were quite a few discussions about that.

Re: Elevated Bridge B/C

Posted: September 11th, 2009, 2:42 pm
by AlphaTauri
croman74 wrote:
AlphaTauri wrote:Sorry if someone has already posted this, but do you think it's more effective to build an "A-frame" bridge or a regular bridge on legs?

Our team never got around to testing this last year before States. (We were more concerned with building a bridge that would actually hold 15kg after our epic fail at Regionals where the bridge broke at 14.87kg. :? )

Thanks!
For that, definitely go to the archived thread of EB and search A-frame. there were quite a few discussions about that.
Yeah, I discovered that right after I posted. Oops. Thanks, anyway.

Re: Elevated Bridge B/C

Posted: September 11th, 2009, 3:56 pm
by T-B
Clear span of 35cm in Division B and 45cm in Division C. 5cm bearing zone on each side. Same as last year, I think.

Re: Elevated Bridge B/C

Posted: September 11th, 2009, 5:05 pm
by danyalukin
Please PLEASE PLEASE advise my team on what type of wood (density, most importantly) we would need to order for bridges!!!
we really need help, best efficiency: 9~~.00 :(

Thanks!

Re: Elevated Bridge B/C

Posted: September 11th, 2009, 6:14 pm
by robotman
most of the time it is design that has more effect on efficency
normally you design your bridge/tower and slowly reduce wood size and wieght till you get the best efficency
untill i had a cometition tower/bridge i got all my wood from the local hobby store because of cost bu the acually size of wood should be in you designs it really depends on design type and what part you are talking about

Re: Elevated Bridge B/C

Posted: September 11th, 2009, 8:31 pm
by dragonfly
danyalukin wrote:Please PLEASE PLEASE advise my team on what type of wood (density, most importantly) we would need to order for bridges!!!
we really need help, best efficiency: 9~~.00 :(

Thanks!
I mean, as someone has surely said somewhere along the way here or in last year's section, the wood necessary for your bridge depends on your design, certain pieces needing more support than others and therefore higher density, yada yada. Not sure if this question is really answerable for anyone but the builder! Sorry :?

(Oops, didn't realize how repetitive that was....oh well)