So which is worse, bored farmers, with 3000 HP pulling tractors and giant sculptures of dinosaurs or bored engineers with rocket-assisted cars and steam powered motorcycles? Or both, competing with trebuchets?
D'wife has remarked several times that Engineers should never be allowed to be bored. The results all too often wind up making headlines and not always in a good way.
Here's my rather modest contribution: A crossbow, made from leftover parts of other projects involving bicycles and old motorcycle parts. I will warn you up front that this thing is not all that close to being finished. I'm designing this as I go along and most of is is subject to revisions, some of which may be quite significant.
The draw on this is a compound stringing method that makes the pull relatively lighter while increasing the pull distance quite a bit. Most crossbows only pull back 6-12 inches but might be as high as 150 lb. The physics of springs says that the energy in a spring is 1/2KX^2 where K is the spring force, and X is the distance it is compressed or extended. More pull distance means less effort to cock it for the same energy for the bolt.
This one uses a rear spring from a motorcycle to supply the force, and the bottom brackets from 2 small bicycles to operate the bow arms which normally do not bend. The chain runs from one sprocket, down through the spring, back up, and around the other sprocket. When the arms are pulled back, the spring is compressed forward. If you want a more powerful bow, you simply attach the chain further around the sprockets, increasing the pre-load on the spring.
It simply cries out for some sort of steampunk decoration.
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