Use the materials collected during the mission to power the Forge.
Unless you are using the payload screen in your dry dock (where all of your accumulated materials are available to be replenished between missions), you will need to group Copernics, Cubic Diodes, Carbides, and Pustrels within the mission it -even if you wish. resupply at the Forge. It's not too cosmic to do, as enemy fighters drop them to death. It's just a matter of flying close enough to suck them up.
There are also items in the environment that can be destroyed for materials, such as Grinner satellites, orange asteroids, and damaged crates, but the majority of Forge materials will be collected from downed fighters. It's absolutely essential that you can deal decent damage otherwise you'll have a hard time powering the Forge and keeping up with resupplies.
Assuming you can harvest the goods you need, using the Forge itself is straightforward. There are four nodes you can interact with, and you can only queue one replenishment each time (with a two-minute cooldown between uses). Depending on your Instrinsic (i.e. Engineering) levels, you will replenish a set amount per charge, and the materials required are listed under the resource you are replenishing. Suppose you burned during repairs and drained your Omni, you can use the four Forge nodes to restock Revolite. Forges will say "Forge Ready" and glow yellow when ready to use.
All Tenno have the ability to replenish the Revolite repairing ship, but if you want to replenish the other three you will need to increase your engineering level. Rank 2 allows you to replenish Flux Energy (the ship's energy for battle and tactical avionics, including Tactical Warframe abilities). Rank 3 will allow you to replenish ammo for your ordinance armaments, and at rank 5 you can do dome charges for the advanced cannon.
Materials are capped at 200 per type in the Forge, and anything collected above that cap is dropped into your personal inventories. If you are collecting more resources than you spend at the Forge, and everything is almost capped, you can use the Refine option to move the materials stored for the Forge to your inventory, but this is generally not recommended. . Say you refine and suddenly fall under fire then you have nothing to replenish.
More often you will use the Refine option after completing the mission and return to the Dry Dock. While the game is supposed to automatically refine these materials when they return can be deleted, so it's best to refine once everyone has agreed to return to the dock.
Remember to coordinate with your crew before using the Forge to see what you need. If you're the Tenno running around fires and boarders, you're likely going to find yourself on blacksmithing duty, so watch out for what's missing and stock up accordingly. Proper use of Forge can be the difference between winning and losing, so even if you're not on Forge duty, check it every now and then.
For more of our Railjack guide series, be sure to check out our guide hub!
-