This script will add recipes to melt down Railcraft's Steel tools and armour, Minecarts (Railcraft and vanilla ones), IC2's Bronze Armour and tools, and MFR's Jailer's Safari Net into Steel, Bronze, and Iron based on the item you input.
1.12.2 version of the script is used in my modpack, Aurora's Adventruer
Requires all of the listed mods to be installed [Especially Tinker's Construct] (or you can choose the script(s) you want to use) and CraftTweaker (or MineTweaker) for Minecraft 1.7.10 or higher.