Looking for full size Dutch Windmill Plans or Blueprints. Is there such a thing out there?

Answer 1

Look in woodworkers.com

Answer 2

I am not sure you are fully aware of how large a full size catapult would be. They were built in a variety of sizes, ranging from about the size of a midsized car to a very large truck. Whatever size you wish to build can be accomplished from any set of plans you find on the internet or in your local library. You may have to use a little math to accomplish this task. You can convert the size suggested in the plans by using a ratio conversion. If you do not understand this ask your math teacher about ratio conversions. I am sure you have or soon will study this in math class.