1. CeAnn Chalker ceann@chalker.org
Towers B & C –
CeAnn Chalker

2. Disclaimer
This presentation was prepared using draft rules. There may be some changes in the final copy of the rules. The rules which will be in your Coaches Manual and Student Manuals will be the official rules.

3. Towers
Students will design and build the lightest structure holding the greatest amount of weight.

4. General Rules Only 1 structure entered per team No Impound
Testing maximum load 15 kg
Students must wear goggles
Towers must be marked by team so judges can identify them
Tower is a single structure (no separate or detachable pieces)

5. Towers Construction
Towers must be made of only wood and bonding glue (any type of glue)
No particle board, plywood, beaverboard, or other composite wood are allowed (this includes bamboo and paper)
Unlimited laminations by students is allowed
No limit on the cross section size of individual pieces of wood

6. Towers Parameters
Must accommodate a loading block that is 5.0cm x 5.0cm x 2.0cm w/a ¼ inch diameter hole in the center
Height – All parts of the loading block must be a minimum 50.0 cm above the platform (no max.)
The base of the Tower must span the testing platform which has a 20.0 cm x 20.0 cm square opening

7. Towers Parameters
No portion of the Tower may extend below the top surface of the testing platform
The Tower may not be braced against the edge of the Test Base
After set up, the Tower may only contact the Loading Block and the Test Base

8. Towers Parameters Division B Parameters Division C Parameters
The portion of the tower more than 30.0 cm above the test base must pass through an 8.0 cm diameter hole or opening
Division C Parameters
The portion of the tower more than15 cm above the test base must pass through an 8.0 cm diameter hole or opening

9. Towers Testing
A chain and bucket will be suspended from the loading block
Structures will be tested by loading sand into the bucket up to 15 kg.
Students will be the only ones to handle their structures

10. Towers Testing cont’d
Students may adjust the tower until they begin loading the sand
Teams are given 10 minutes to load the sand into the bucket

11. Towers Testing cont’d Sand loading stops –
When failure of the tower occurs
When maximum load is supported (15 kg)
When the chain comes in contact with the tower
When any part of the tower extends below the top surface of the Test Base

12. Towers Testing cont’d Load Supported includes – Loading block Eyebolt
Washer
Wing nut
Bucket
Sand

13. Towers Scoring Formula
Score= Load Supported (grams)2/Mass of Tower(grams)
Highest Score wins
Tie Breaker
Ties will be broken in favor of the lighter structure

14. Towers Tiers 1st Tier 2nd Tier Tower meets all Construction Parameters
Tower does not meet one or more Construction Parameters

15. Towers Tiers cont’d 3rd Tier
Structure can not be tested for any reason will be ranked by the lowest mass