Crafting weapons require a Weapon Toolkit and 7 Metal of the appropriate quality. The assembly pattern depends on the type of weapon to be crafted:
|You can remodel a weapon with a Casting Toolkit and another weapon of the same class whose look you want (this weapon will be destroyed in the process). Place the Casting Toolkit and the weapon whose look you want into the Assembly window, click the Assemble button, and you will receive a mould of the weapon. Then place the weapon whose stats you want and the mould in the Assembly window and click the Assemble button.|
Auxiliary weapons (such as the rocket launcher or chainsaw) must be obtained from a mission and are not able to be crafted. However, the weapon you receive can be upgraded using Auxiliary Upgrade Toolkits (blue or purple). These toolkits are dropped from Nightmare mode dungeon bosses.
For information on upgrading and customizing endgame weapons, see Endgame Gear Guide.