Redsmith Crucible Set

Alter: This set of magic smith's tools from the dwarven Redsmith family includes a stone crucible that's been enchanted with minor transmutation magic. If you are proficient with smith's tools or are a dwarf, you can use an action to speak the tool's command word and lower a nonmagical weapon made of metal into the crucible and hold it there for 10 minutes. At the end of that time, make a DC 10 Strength check using the smith's tools. On a success, the weapon is magically reforged. A reforged weapon counts as magical, and when you pull the reforged weapon from the curicible, you can change it into another type of weapon that shares the same properties as the original one. For example, a light hammer can become a handaxe, or a longsowrd can become a warhammer. These benefits last for 24 hours, at which point the weapon becomes nonmagical once more and returns to its original form.

Once this property of the tools has been used, it can't be used again for 24 hours. In the meantime, the tools can still be used as magic smith's tools.

Attunement: No
Rarity: Common
Type: Tools
Cost: 50gp

Griffons Saddlebag, Vol II

a magic smith of sufficient skill can use this item to permanently change the shape of nonmagical weapon, or a magical one. with each, the crafting time and DC increase.

Knot Redsmith