Mass Production is an achievement/trophy in the Fallout 4 add-on Contraptions Workshop.
Requirements
Produce 100 objects from builders.
General Information
The needed builder can be found in the Workshop Menu under Power > Manufacturing > Machinery > Builder. It requires 2 circuitry, 3 gears, 4 rubber and 10 steel to complete and is the base component for mass conversion of junk items. Conveyor belts, hoppers and sorters may also be created and linked to the builder, but are not a necessity.
Once created, the builder requires 8 power to operate and can be achieved with three small generators, one small and one medium generator, or one large generator. The small and medium generators must be linked in tandem in order to successfully power the builder. Once powered, access the builder's inventory and transfer as many items as possible. Once items are transferred and the builder is powered, it will automatically produce new items.
One builder will take 30 minutes or so to unlock the trophy/achievement. Naturally, more builders will unlock the trophy/achievement faster. Three builders will take approximately 10 minutes and six builders will do it in about five.