Hopper
While it appear deceptively simple (it's basically a box with a hole in it), the Hopper allows the construction of many advanced mechanisms. Any items that fall into the top of the Hopper are added to its inventory. If the Hopper receives Mechanical Power through axles mounted to its sides, it will begin to eject items from its inventory (and stop when the power is cut) out the spout below. Items may be ejected into the air, or directly into any other Block that has an inventory (chest, dispenser, cauldron, etc.), and it is also capable of eject its contents into a storage minecart parked beneath it. Also, if all the slots in its inventory contain items, it will send out a redstone signal warning that it is getting full (the signal will stop when there is an empty slot in the inventory).
Crafting
Filtering
The Hopper also contains an extra inventory slot in which you may place various items that act as a "filter" on which items it will swallow. Filtering hoppers can be placed in a trench so water will wash Items/Drops over every hopper. The water must decent one block after each hopper to avoid jamming.
| Filter | stops | passes | passing Examples |
|---|---|---|---|
| Ladder | blocks | Items | |
| Hatch | max. Stack<64 | max. Stack=64 | pork chops, eggs |
| Grate | large Items | small Items | feathers |
| Wicker | not powdery | powdery | gunpowder, flour |
Note that the Hopper will not eject clay balls if they are placed inside of it (it gets stuck to the sides). As such, clay balls can be used as a "filler" within the Hopper inventory, allowing you to control precisely how much space is available to store other items within it.
Applications
- Automated Chest loading
- Automated Drop sorting
- Automated Refilling of any Block that has an inventory
- Automated storage-mine cart loading
Keep in Mind
- The Redstone signal the hopper emits if no empty slot is available will reach the block beneath it. So a booster rail will be powered if the hopper is becoming full. To stop the minecart from escaping and causing the hopper to spill its content into the air place a detector block so it can place a solid block next to the booster rail. With this design you can trigger the minecart when the hopper has been cut from mechanical power.
- A filtering hopper will cause the not swallowed Items/Blocks to be a bit lower so they get stuck if a full block is placed downstream of the water conveyor. You can place hoppers next to each other to avoid jamming but separating the falling drops afterwards is quite complicate so building a row of sorting hopper with a incline is a lot easier, compact and will generate the two block distance needed for chests.
Demonstration Video
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