Boomilever
DESCRIPTION:
The objective of this event is to design and build the lightest boomilever capable of supporting a given load. The boomilever is a cantilevered wooden structure, which will be attached to a vertical testing wall at one end, and supporting a load at the distal end.
A TEAM OF UP TO: 2 MAXIMUM TIME- 10 minutes
THE COMPETITION:
Materials:
1. The boomilever is to be a SINGLE structure constructed of wood and bonded by glue No other
materials shall be used. Bamboo is not a wood.
2. The boomilever must be constructed of pieces of wood no larger than 1/4" high and 1/4" wide Anv
dowels used cannot have a diameter greater than 1/4". ' -
3. It may have an attachment base which may be of any type of wood not to exceed 30 cm x 15 cm x 1/2 thick. The attachment base MUST be permanently attached to the boomilever
4. Particleboard, wood products, or commercially laminated wood may not be used, except for the attachment base.
5. There is no limit on the length of individual wood pieces used in the construction, with theexception
noted for the attachment base. '
6. Any type of bonding material (glue) may be used
7. The boomilever will be attached to the vertical-testingwall with one or two 2 inch long 1/4" threaded
bolt(s), washer (not to exceed 3/4' diameter) and wing-nut through the holes in the testing wall. The bolts will be placed so that the head of the bolt is on the same side as the boomilever.
8. The center of the loading block will be placed on the boomilever beam a minimum of 400 mm from the vertical-testing wall.
9. The load will be applied to a loading block by an eyebolt and S-hook
10. The loading block will be 50 mm long and 50 mm wide and 20 mm high.
11. A bucket will be attached to the S-hook attached to the loading block. The loading bucket will be a standard 5-gallon plastic bucket (30 cm in diameter).
12. The student will add sand to the bucket.
13. Maximum allowable time for set up and loading will be ten minutes. If the time expires, the bridge is ranked with those that could not hold the 15-kg.
14. The student will add sand to the bucket until failure occurs or the maximum load (15 kilograms) is supported. The maximum load (15 kilograms) incorporates the total mass of the loading apparatus, bucket and sand.
15. Boomilevers that experience failure before reaching 15 kilograms will not be disqualified.
16. Failure is defined as the inability of the boomilever to carry additional load without breakage or inability to hold the maximum load for 5 sec. Excess sand added after failure will be removed by the event supervisor.
Construction:
1. All construction must be completed prior to impounding at the tournament
2. Sound engineering practices such as good truss construction, gussets and mitered joints are
3. Do not coat the boomilever with any material (i.e. paint, stain or glue)
4. Unlimited lamination (i.e. bonding together layers of wood) by the student is allowed. Commercially
laminated wood is only allowed for the attachment base.
5. The boomilever must be constructed to meet the following parameters-
a. It must be designed in such a way that it can be attached to the vertical-testing wall with one
or two 1/4 bolts. The bolts will be precisely 20 cm apart on center horizontally The
boomilever may have an attachment base (which may be one or two separate pieces)or designed
in such a fashion that it can be attached to the Testing Wall.
b. The boomilever must support the loading block at a minimal horizontal distance of 40 cm
from the vertical-testing wall.
c. No part of the boomilever may touch the vertical-testing wall further than 15 cm below the
attachment holes.
Testing:
1. All boomilevers are to be impounded by the event supervisor prior to the start of the competition
After testing, it may be taken away
2. No alterations will be allowed to the boomilever once it is submitted for competition.
3. All boomilevers will be assessed prior to testing for construction requirements and dimensions by the
even i supci'vi sor.
4. Students must wear eye protection, which they must provide, during loading and testing
5. The event supervisor will provide the loading block, testing wall, attachment hardward and loading material.
6. The vertical-testingwall will bea pieceot-3/4" thick plywood or other suitable material around 45 cm wide and 30 cm high with two 1/4" diameter holes 20cm apart on center horizontally 5 cm from the top.
SCORING:
1. The score (Structural Efficiency) will be determined by the equation: Structural
Efficiency = Load Supported (grams) / Mass of Boomilever (grams). The maximum
load supported cannot exceed 15 kg.
2. The Boomilever that held all 15 kg for 5 sec. with the highest structural efficiency
would be the winner, followed by all other boomilevers that did the same.
3. Boomilevers that meet all the specifications under Materials and Construction, and
held the entire 15 kg but for less than 5 seconds will he ranked next.
4. Boomilevers that meet all the specifications under Materials and Construction, but
did not hold the entire 15-kg will be ranked next.
5. All other Boomilevers with construction and material problems will be ranked next
in an appropriate fashion.
6. Teams whose Boomilevers cannot accommodate the loading block will be awarded participation point(s) only.
2002-CC21