Blacksmith

A Blacksmith is a type of shop, specializing in smelting metal into workable ingots and using those ingots to create weapons, armor, and other metal items.

Downtime Activity: Training
You can spend time with an instructor here to proficiency with Smith's Tools.

Resources. Receiving training in a language or tool typically takes at least ten workweeks (50 days), but this time is reduced by a number of workweeks equal to your Intelligence modifier. A negative Intelligence modifier doesn't increase the time required for training. In addition you need to find a teacher and pay 25 gp per workweek.

Resolution. At the end of your training, gain that new tool proficiency.

Downtime Activity: Crafting
If you are proficient in Smith's Tools and you're on good terms with the proprietor of this establishment, you can use the facilities here to create mundane armor and weapons.

Resources. Crafting an item requires you raw materials worth half the item's selling cost. The time in workweeks required to craft an item is its base price in gold pieces divided by 50. You can create multiple items in a workweek if the total cost of those items is 50 gp or lower. Items that cost more than 50 gp can be completed over long periods of time, as long as that work in progress is stored in a safe location.

Multiple characters can combine their efforts. Divide the time needed to create an item by the number of players working on it. A particularly tiny item, like a ring, might only allow one or two workers at a time, whereas a larger, more complex item might allow for four or more workers. A character must be proficient with the proper tools to craft an item and must have access to proper equipment.

Resolution. Once the proper materials are collected and the proper time has been spent, you successfully craft the item. You can sell the crafted item at its listed price if you so desire.