First, a short digression into history. Trebuchet is a medieval throwing machine. It was used in sieges of cities and fortresses. Shells for trebuchet were stones.
In the USA, trebuchet are used in pumpkin throwing competitions. The master built a not quite classic model. This trebuchet has fewer parts and differs in the way it is driven.
The largest trebuchet made by the master weighs 226 kg at a height of 3 m. Using this trebuchet, the master threw a 2-pound pumpkin at a distance of 213 m.
In this instruction, the master will tell you how to make a trebuchet with a height of 1 meter and a weight of 9 kg.
Tools and materials:
-Lumber;
- dowels;
- Sticks for ice cream;
-Fasteners;
-Cord;
-The cloth;
-Metal for counterweight;
- PVC pipe;
-Marker;
-Hacksaw;
-Hammer;
-Electric drill;
- Metalwork keys;
-Scissors;
-File;
-Vise;
-Burner;
Step One: Project
As can be seen from the photo below, the trebuchet design differs from the classical lack of a fixed base. The master had the task of simplifying the product as much as possible without compromising the propelling characteristics. Aiming, in this case, is not so important. The trebuchet consists of a bed in the shape of a triangle and a throwing lever. The spikes are fixed on the bed, which does not allow the triplet to turn over when in contact with the ground. On the lever are mounted, on the one hand, a counterweight, on the other a sling bag on a rope.
Step One: Throwing Lever
For a lever, you need a board of 91.44 x 7.62 x 1.27 cm. The lever has two ends, the lower with a sling bag, and the upper with a counterweight. At a distance of 50.8 cm from the bottom edge, the master drills holes for the axis. In the lower part it measures 2.54 cm and cuts the wood into a cone, to the hole (i.e. where the hole is 7.62 cm, and below 2.54). Measures from the hole 37.4 cm up, cuts the rest.
From the end of the cone, the master drills a hole and installs a thorn metal spike.
Step Two: Bed
This is of course not quite a bed, but, in order to avoid confusion, we will adhere to the name of the parts, as in the classical trebuchet.
The bed is an isosceles triangle with sides of 50.8 cm base and 58.4 cm sides. A throwing lever will be attached to the top of the triangle. The master prepares the details of the bed.
Collects a triangle.
On the front side (the one that will abut against the ground) Drills holes and secures the spikes.
Step Three: Hook
To hold the throwing bag, the master makes a hook (by analogy).From a previously drilled hole in the throwing lever, down, measures 10 cm. Drills the holes. Fixes ice cream sticks on both sides.
Step Four: Sling Bag
A sling bag can be made from a piece of fabric or mesh. It is a square with sides 25 cm. In the center of the square, the master makes a pocket. To do this, he cuts four holes and pulls the fabric through them with ties. On the same axis with a pocket, at the edges of the bag, the master makes knots.
Tie a rope to the knots. The length of the rope is about 76 centimeters.
At a distance of 5 centimeters from the lower edge of the lever, the master drills a through hole and pulls the end of a sling rope through it. The rope should not be stretched from the conical side, but from a straight line. Having stretched the rope, the master ties a knot so that it does not stretch back. At the end of the second sling rope, the master makes a loop. Now you can try how the device works.
Step Five: Counterweight
On the upper end of the lever secures the base for the counterweight.
Secures the load.
Step Six: Build
At a distance of 38 centimeters from the top of the triangle, on each side, drills holes and fastens the rope. The length of the cord (between the two slats) is 40 cm. Using this cord, it will be possible to adjust the range of the projectile.
Attaches a lever to the bed. Installs washers between the connecting parts. The lever and bed should be easily rotated on the axis.
Seventh step: tags
On the lever, the master makes small cuts and draws marks. The cord of the bed will catch on the grooves.
Now you need to charge the trebuchet and conduct tests. You can understand how to do this by watching the video.
There are many ways to adjust trebuchet. Using the position of the triangle (adjustable cord). Using the length of a sling rope (difficult). Using the position of the hook.
Step Eight: Platform
For competitions, the master launched the trebuchet from a special platform. Using the platform is safer for the starter. As shells, balls filled with water were used.
Here is such entertainment for children, adults and even, judging by the video, animals.
