Grinders

Grinders is an optional mission in Borderlands: The Pre-Sequel. It unlocks the Grinder, the game's mechanism for converting unwanted items into more useful ones.

Objectives

 * Destroy grinder buggy
 * Pick up grinder buggy piece(?)
 * Get grinder piece from scavs
 * Don't ask nicely
 * Hit grinder
 * Kill Rooster
 * Pick up explosives
 * Place explosives on grinder
 * Set up detonator
 * Activate detonator
 * Pick up recombinator
 * Talk to Janey
 * Put grinder parts in grinder
 * Pick up assault rifles
 * Put assault rifles in grinder

Strategy
Janey first sends the vault hunter in search of a moon buggy patrolling the southwest area of Triton Flats. When destroyed, it drops one of the grinder pieces Janey needs to repair "Bessie". The moon buggy behaves like a standard enemy buggy that fires missiles.

The next piece is in Stanton's Liver. Janey tells the vault hunter to retrieve this part from the scavs there, and "don't ask nicely". (Killing them suffices.)

Partway through the area, the leader of the local scavs, Rooster, announces himself and taunts the vault hunter. The part in question is at the other side of the area, on the roof of the St. Pancreas train station. When there (and after clearing the enemies), Janey asks the vault hunter to hit the device. It doesn't yield, but Rooster appears - a badass scav. When killed, he drops three explosives and a detonator. Janey has the vault hunter set the explosives on the device and detonate them from a safe distance, leaving the recombulator behind.

Back in Concordia, the vault hunter repairs the grinder by inserting the two parts, then gets a demonstration of its use when Janey offers three common assault rifles to put into it and grind.