T R E B U C H E T

1
T R E B U C H E T

• A Semester-Long
• Engineering Project
• By ANDREW ALTON

2
Why did I do this?

• Pent up rage
• Destroying People/Things
• Weapons at school
• Nothing better to do
• on Mondays and Wednesdays
• anymore

3
RESEARCH
Data-Variables

• Only few internet sites w/ worthwhile info
• How-To Websites
• www.trebuchet.com
• A Treb computer
• variables ? data

Cool Simulation
4
The BUILD

• Every Monday and Wednesday
• around 6-9 PM
• Tools from home
• THE HOME DEPOT
• Mr. Dohm reimburses me for the 200
• I spent on materials

5
The Start

• Used old trebuchet(s) from last semester
• Used about 40 old materials, 60 new materials
• Basic plan Make the old trebuchet into one that
  works very well and launches a projectile

6
Components of a Trebuchet

• Long, very strong Arm
• Axles must not bend
• Should have wheels
• Counterweight heavy compact
• Sling launches projectile farther
• Trigger? safety first!

7
The ARM
Holes must be bored perfectly level, so arm is
plumb.

• Triple 2X4 construction

8
Axles

• Cotter Pins Hold Arm from moving horizontally

Axle Grease
More cotter pins so axle doesnt come off supports
Screwing it together is easier
9
The Counterweight

• First tried concrete
• Then looked all around for weights
• HOME-DEPOT paving bricks
• Cheap real HEAVY
• 30 bricks X 5 lbs. ea.
• 150 lbs.!!

10
S l i n G

• No pre-made slings made it myself
• Sewing strap-stronger
• One end of sling string is attached to trebuchet,
  the other is attached to a metal ring- slips off

11
Trigger

• Launch trebuchet from a safe distance
• Heavy duty construction meant a safe launch
• About 100 lbs. of force
• Slip metal ring attached to the arm over the
  trigger rod.
• Stick a screwdriver shaft through eyebolts
• Pull screwdriver out with an attached string

12
Final Product

• Arm is strong and efficient
• Outriggers keep trebuchet from wobbling
• Swiveling wheels allow easier transportation
• Center channel guides projectile

13
Testing

• First couple tests- trebuchet fell completely
  apart
• Next tests with bricks- bricks fell out of
  counterweight box
• Added blue tarp on counterweight box to keep
  bricks in
• Tried different projectiles Water Balloons,
  Concrete Ball, Steel Shot-Put, Then a Large Rock.

14
Movie Of Trebuchet Trial
15
Second Movie of Testing
16
MY FUTURE TREBUCHET

• Counterweight
• 2 X 55 gal. Drums w/ Water 990 lbs.
• Perfect for launching Underclassmen, preferably
  Froshes!
• Beware!..