First off, you'll want to navigate to the following file:
L:\Steam\steamapps\common\7 Days to Die\Data\Config\items.xml

• Personally, I prefer to use notepad++ to edit these files because it's just easier but you can use normal notepad if you desire.

Open the file.

So, for Raw Iron (the chunks of iron you mine in-game,) you'll want to navigate to: name="resourceIronFragment" TIP: Press CTRL+F to open the search function.


We'll want to focus on the Weight of the material. By default, the weight value of "resourceIronFragment" is set at 5. That's how many seconds it will take to smelt. Increasing it to 8 makes it take longer, and decreasing it to something like 1 makes it smelt instantly.
NOTE: Do NOT use decimals in the weight. (EX. 0.1 or 2.3) The forge will eat your resources and won't give you anything.

You can do the above to every item/resource that has weight. Decreasing/Increasing the values decreases/increases the speed.

EDIT: Recently I've learned that decreasing the weight also decreases the total amount smelted. So for example, originally, smelting a raw iron would grant you like 5 pieces of iron or something like that. Decreasing the weight to 1 increases the speed, yes, but it only gives you 1 piece of iron.

THAT is why we focus on the melttimeperunit line of text. Decreasing/increasing this value decreases/increases the actual smelting time (I should've seen this earlier BUT I read online that it no longer worked so I have no idea if changing the value actually works or not, haven't tested it yet.)

Navigate to:
L:\Steam\steamapps\common\7 Days To Die\Data\Config\XUi\windows.xml

Open the file with either Notepad or Notepad++

Using the search function (Ctrl+F), locate: name="Content"


In that chunk of text, search for the text rows="1" (it should be around line 722)

Change the value from "1" to "2"

Afterwards, you can edit the surrounding in-game windows to make your Forge Smelting window neater and cleaner.