The Grinder is a machine in Borderlands: The Pre-Sequel which allows you to combine 3 items into a new, potentially better item. You unlock the ability to use The Grinder when you complete the optional quest “Grinders” from Janey Springs when she is in Concordia. The great thing about the grinder is that you can take items which you don’t like or want and using specific grinder recipes you can grind those unwanted items into a specific item type which you want. When grinding items you can choose to either grind the items together regularly or you can utilize a moonstone grind which costs moonstone but guarantees you a better item quality level and also has a chance to add a special Luneshine bonus to your weapon. Below is a list of the potential Luneshine bonuses which you can get on your weapons through moonstone grinding.

Luneshine Bonuses:

• Boominator: +5% grenade damage
• Fast Learner: +XP from kills
• Harden Up: +3% maximum shield capacity
• Oxygenator: +1 O2 unit after damaging an enemy
• Piercing Rounds: +30% chance to ignore shields
• Punisher: +10% critical damage
• Safe Guard: +3% capacity added to shields on kill
• Serenity: -20% O2 consumption rate

Grinded Item Level:

The base level of a grinded item is based upon the levels of the items you used to create it. It seems to be some type of weighted average, however it’s not a median or mean average. For example, grinding together 2 level 23 gold weapons & 1 level 50 purple rocket launcher resulted in a level 28 gold rocket launcher.

Recipes:

The most common recipe in the game is to combine 2 or 3 items of the same type & quality which guarantees you a new item of that type and a chance for it to be the same or one level higher quality. If you use a moonstone grind to create the item you guarantee that the new item will be one grade higher quality level. The exception to this rule is with Purple & Gold weapons. Purple weapons cannot be grinded together to create Gold Legendary weapons. Instead the recipe for creating a Gold legendary item is to combine 2 gold weapons of any type with a purple weapon of your desired type in order to create a new purple or gold legendary weapon of that type. Below is a list of known Grinder Recipes in Borderlands The Pre-Sequel:

Grinder “Recipe”	Resulting Item	Notes
1 PURPLE rare weapon of the desired type + 2 ORANGE legendary weapons	New ORANGE legendary weapon of the desired type	Non-moonstone grind can result in a PURPLE weapon
2 BLUE weapons of the desired type + 1 Additional BLUE weapon	New PURPLE weapon of the desired type	Non-moonstone grind can result in a BLUE weapon
3 BLUE weapons of different types	New Random PURPLE weapon	Non-moonstone grind can result in a BLUE weapon
2 GREEN weapons of the desired type + 1 Additional GREEN weapon	New BLUE weapon of the desired type	Non-moonstone grind can result in a GREEN weapon
3 GREEN weapons of different types	New Random BLUE weapon	Non-moonstone grind can result in a GREEN weapon
2 WHITE weapons of desired type + 1 Additional white weapon	New GREEN weapon of the desired type	Non-moonstone grind can result in a WHITE weapon
3 WHITE weapons of different types	New Random GREEN weapon	Non-moonstone grind can result in a WHITE weapon
3 BLUE items of the desired type (Shields, Oz Kits, Class Mods, Grenade Mods)	New PURPLE item of the desired type	Non-moonstone grind can result in a BLUE item
3 GREEN items of the desired type (Shields, Oz Kits, Class Mods, Grenade Mods)	New BLUE item of the desired type	Non-moonstone grind can result in a GREEN item
3 WHITE items of the desired type (Shields, Oz Kits, Class Mods, Grenade Mods)	New GREEN item of the desired type	Non-moonstone grind can result in a WHITE item
1 SMG + 1 Sniper Rifle + 1 Shield of the same rarity	New Assault Rifle	Recipe items must be WHITE, GREEN or BLUE. Non-moonstone grinds can result in the same or +1 rarity.
Any 2 weapons + 1 Grenade Mod of the same rarity	New Rocket Launcher	Recipe items must be WHITE, GREEN or BLUE. Non-moonstone grinds can result in the same or +1 rarity.
1 Pistol + 1 SMG + 1 Shield of the same rarity	New Shotgun	Recipe items must be WHITE, GREEN or BLUE. Non-moonstone grinds can result in the same or +1 rarity.
1 Assault Rifle + 1 Pistol + 1 Shield of the same rarity	New SMG	Recipe items must be WHITE, GREEN or BLUE. Non-moonstone grinds can result in the same or +1 rarity.
1 Assault Rifle + 1 Shotgun + 1 Shield of the same rarity	New Sniper Rifle	Recipe items must be WHITE, GREEN or BLUE. Non-moonstone grinds can result in the same or +1 rarity.