Required Map: The Split (Only of the initial 32 maps to have a fabricator), added to Escape on 10/06/2020
As this is only for the fab achievement, you can get it with any character on Beginner, once you have started the match follow the natural course of the map, on the first split take the right path...
Theres gonna be a set of 3 staircases in a long section, go down below any of those staircases and you'll have the fabricator in front of you, get close to it, hold X and grab a weapon, you have enough energy on the fab to aquire it, achievement unlocked.
There's 3 fabricators in this first section, so everone should get it without any issue, every fabricator has enough energy to aquire 1 weapon, if the door is opened and it shows 0 energy, someone already got a weapon from there, use the next one.
As you enter the room, the fabricators will have the following Weapons:
Fab 1: Buzkill/Mulcher
Fab 2: Boomshot/Dropshot
Fab 3: Lancer GL/Claw
If you run to any fabricator be careful, sometimes drones spawn downstairs on each section.
On the second section of the map, after the safe room, you can find more fabricators again on the right side after the first split, but there's Guardians/Sentinels nearby, so you need to be more careful to get them.