fallout-4
Let's say I have 10mm pistol. Can I break it down so I'm left with no pistol, and a [barrel, magazine, sight, grip] etc?
I ask because I'm finding myself in the early game with mods across 3-4 pistols that I'd like to combine into one, but I lack the extra junk/spare mods to swap things around.
Actually you can put all your junk directly in your workshop and just leave it there, you never have to pick it back up before crafting.
With all your junk in your inventory, simply interact with your workshop and press the button to "Store all junk" (Y on Xbox controller) and it will automatically store ALL your junk in your workshop. You can then still transfer some back to your inventory if you wish.
Normally this works only for a single settlement (junk/ressources are shared throughout every workshop/crafting station of said settlement) -- the junk is only where you've left it. You can however get "Local Leader" perks which enables you to set up trade routes which allow for sharing junk between settlements.
It's uh... yeah. It's a little complicated. And unfortunately the game doesn't make this at all clear.
It all revolves around the Workshop.
You can break down five types of items into their components:
Three benches affect component creation:
When broken down, the components go to different inventories:
The components that are available to you for crafting are a combination of:
To get needed components, the Workshop:
You don't have to break these down to access their components.
Let's say you have a Plastic Plate in your inventory. When broken down, that's worth two plastic. But those two plastic are available as raw materials without a separate step of breaking them down.
These materials are available for Workshop and Workbench crafting whether they're in your inventory or the Workshop's inventory.
It's also possible to break them down manually the same way as for neighborhood debris as described later: by dropping them on the ground and manually scrapping each one. (Infrequently when you drop an item on the ground it will disappear—falling through the ground or into another object—so you might want to back up before doing this.)
Why would you bother to break down junk manually? If you plan to keep these items in your inventory for their components, for example to move them to another settlement, the components themselves will usually be much lighter than the original item. Note the usually though. Examples:
(That last one is presumably because concrete = cement + sand/gravel/stone.)
Moddable weapons act differently from junk in that you must break them down at the Weapons Workbench.
Let's say you have an Automated Institute Pistol, which includes plastic as a component. That potential plastic is not available for crafting.
To make it available you must go to the Weapons Workbench, select the weapon, and use the Scrap command. This will place those components in your personal inventory.
While this is an extra step, it makes sense. If the Workshop automatically melts down a wrench in your inventory, that's great. If it melts down your beloved laser rifle... yeah. That sucks.
It is not possible to break down non-moddable weapons (for example grenades), even by dropping them and using the Workshop menu.
Armor that can be modded works the same way as weapons: you must break it down to make its components available. You break it down the same way, but using the Armor Workbench. This will place the components in your personal inventory.
Other apparel, including clothing and non-moddable armor like helmets, must be broken down the same way as neighborhood debris, which is described in detail next.
As with moddable armor and weapons, the Workshop will not break down these materials automatically. You must do it manually.
For all the debris near a Workshop—walk up to the Workshop bench, choose the Workshop option, and then walk away from the Workshop.
As you walk around your neighborhood, items will get highlighted with the option to Scrap them. Choose that option and they'll get broken down -- you can even break a car, tree, or collapsed house into its components in seconds.
Unlike the Weapons and Armor benches, breaking items down this way places them directly in the Workshop inventory rather than in your own. This makes sense: if you break down an entire house, you don't want to carry it around in your pockets.
While in this mode, you can see the Workshop's area of influence as a translucent green wall around the region.
You can generally activate the Workshop crafting menu from anywhere within the Workshop's area of influence: hold down whatever key, mouse button, or controller button you have mapped to "Toggle POV/Workshop". (Look at the Workbench and it'll tell you the key.) Just be sure you're not looking at another item, like a container, when you hold down the key, or the Workshop menu might not appear.
Note that if you're in the Workshop menu and have selected an item to create, you won't be able to Scrap items you find. Press Tab to break out of item creation mode and back into the main Workshop menu.
Components in the Workshop inventory are available for Workshop and Workbench use within that Workshop's entire area of influence.
By default it's not shared between Workbenches in different settlements. As discussed in this question, you can set up a supply line to share resources between settlements.
Many people believe that when the Workshop automatically breaks down a junk item to get a specific components, the other components are lost.
While this is a widespread belief (and for good reasons), it's not true. Details are in the accepted answer to the question What happens to extra materials from salvaged junk?
Best Answer
It's not possible to do this without any component cost. Scrapping a weapon destroys its mods.
But it shouldn't take long to find a few spare weapons, break them down, and make enough components for a swap at a relatively low component cost. If you can manage to afford the Level 1 Scrapper perk this gets even easier.
It sounds like you might know how to do this already, but in case it helps you or others—let's say you have a Powerful Receiver mod on pistol A, and you want to move it to pistol B.