how do you build a trebuchet?

Question

with a throwing arm length of 24 inches, and a base with a max of 2 by 3, counter weight undecided. very important 2 know as soon as possible

Answer 1

The site below may give you some specifics, it also has lots of links to other sites........:D

Answer 2

There are many plans online to build one; I recommend this free program to determine your parameters for what you wish to achieve in range and payload:

http://www.algobeautytreb.com/