Include the class of weapon, i.e., small guns, big guns, explosives, pulse weapons... what they do and the amount of damage they would produce, their name and the parts required to make em.
For example I would like to be able to stand at my work bench and make a...
POP-UP MINE
Class - Explosive
Recipe
Lunch Box
Lawn Mower Blade
Cherry Bomb or Bombs
Automobile suspension spring (not currently available by scrounging)
Upon completion and placement the mine would explode
(triggered by proximity you would not have to actually step on it.)
The lawn mower blade would "pop up" spinning like crazy and would dismember or perhaps decapitate the enemy.
Damage no less than 50
A critical hit would always be decapitation and would always be fatal, of course.
Lets see your ideas gang!