Junkyard Challenge B

[Freyssenet]

Hello all, I would like to ask those who have experience in this event. Would guyed towers count as self-standing? This is providing that the "cables" made out of tape or string are tied to counterweights and not directly to the test base.

[ohiostar]

Just finished Solon Invitational in Ohio, the challenge was "bridge" We were provided a space to build on the floor then after the 30min. time we were asked to move our bridges on top of two tables which were moved as far apart as our bridge would allow. One end of the bridge was on a table and the other end of the bridge sat on a seperate table with the span of the bridge over the gap. Then the 2 minute period for testing/judging began.

The judges scored by measuring between the tables.

Does this sound correct, may bridges saged in the middle well below the table height - teams with the saging bridges were considered legal. If the gap between the two tables was not present the saging bridges would have touched a table top or floor depending on how they were set up.

How does one practice for these events when the rules are interpeted in so many way? Look at the FAQ's in the S.O. web site by far the most questions submitted are for Junkyard.

The winning bridge was constructed of two parellel strings with weights at each end and a plate in the middle - the span was extremely large probably 10ft. (conservative) when placed between the tables the cup and ball were inches from the floor.

Frustrated in Ohio

[wlsguy]

You will need to have different techniques based on the testing style.
I agree, in looking at the photos in the rules, it appears the bridge span must be higher than the testing surface.
It is not specified so each event supervisor can choose their own setup.

This is one of the frustrating (but learning) oppertunities. You need to be able to adapt.
As long as the event supervisor shows or explains the testing setup before you start building, I think the variables are just part of the event.

[kelbyp]

My partner and I got first at invitationals. We had a bridge that spanned 22' 4". It was NOT on/between tables.

[ohiostar]

The winning bridge at the invitational I mentioned (Solon, OH) was scored at 6,860 mm (22.5 feet). The problem with the judging was that parts of the bridge were allowed to contact table edges, the span sagging almost to the floor was considered legal.

[akmshr07]

What kinds of distances are you guys getting for the catapult? It says it will be measured in mm so its probably not expected to be too big.
Also it never specifies what the catapult must be powered by, could it be rubber bands (like trajectory) and/or weights (like storm the castle)?

[fleet130]

Specifying the measurement will be in mm is only stating the resolution and standardizes the score. It should not be taken to imply only short distances are expected. Distances achieved could be in the 10s of meters range (10<distance<100 meters).

[mnstrviola]

What materials have you found to be the most effective as a counterweight/weight? I think golf balls would probably work best , but I'm not sure

[akmshr07]

What materials have you found to be the most effective as a counterweight/weight? I think golf balls would probably work best , but I'm not sure

tennis balls are heavier (tennis balls 60 grams, golf balls 45) but golf balls take up less space so its up for grabs as to the best weight.

[The Architect]

I have a solution to the height problem in towers. It is possible to use leftover materials in your box to create something that one can place the ball upon, pick up with one's arm, raise, and then tilt so that the ball falls into the cup on top of the tower. An extension of the arm if one will call it so.