The FAT/F2K Trebuchet Plans
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The FAT Trebuchet PLANS

What's included with these plans:

These plans are available in downloadable PDF format only. The download instructions will be emailed to you on receipt of payment.

Only $14.95 Click here to buy!

The Floating Arm Trebuchet is the most revolutionary design in trebuchet technology since the middle ages. Invented by Ron Toms in 1998, the FAT uses modern engineering principles to increase the efficiency of the medieval trebuchet. The Medieval Trebuchet was the most mechanically efficient throwing machine ever invented, a status that it held for over six hundred years, until the development of the FAT! (FAT style machines have been built with over 80% mechanical efficiency)

In early 2000, Ron modified the design (now called the FAT-2000, or F2K) to double the amount of power available in the machine. Some efficiency was lost, but the increased power more than made up for the small loss in efficiency. This three-foot tall machine, weighing about twenty pounds- including counterweights, is capable of hurling a golf ball the length of an American football field.

The main difference between a traditional Trebuchet and a Floating Arm Trebuchet is that the main throwing "arm" has been de-coupled from the frame, and the counterweights are constrained to fall exactly vertically, the way gravity works best. By de-coupling the arm, it is allowed to "float" on a series of wheels rather than just spin on an axle. This improves performance even more.

It's a great science experiment, and a great model just to have fun with for a different kind of target practice.

Tools you will need to make this kit:
- Table saw
- Mitre saw or chop saw
- Drill press
- Screw driver
- Glue
- Clamps
- Scissors

Designed by catapult and trebuchet expert Ron Toms, this machine is easy to assemble, and it really works!

We've put a lot of time and effort into making this plan as easy and complete as possible. It's a great way to learn about trebuchets!


$14.95 Click here to buy!