2.50 items a second · 22 blocks

Empties full shulker boxes into a chest and sends the empty boxes out (2.50 items a second).

tiles side by side and keeps sending boxes out with its chests kept full · timed with 64-stack items · empties a box in about 11½ min · fits in 1×7×6

always on, no lever16-stack items toounstackable items tookeeps box colours and names+3 more

2.50 items a secondShulker box unloader3D view loading (or not available in this browser)

Try it

Press play under the view to start it. Watch the items and boxes move between the chests (the numbers over each container show what it holds); the speed dropdown goes up to 100×.

How this design does it: A one-block-wide shulker unloader you can line up side by side with no gap (22 blocks): a dispenser drops each full box onto a hopper that empties it, and when the box is empty a piston pushes a block into it, which breaks it into a second hopper that sends it on.

Build it

Download .litematic Download the design as text

The .litematic opens in Litematica (Minecraft 26.3): every block of the design in one region. The text file is the same build written as plain text, block by block.

Blocks used: comparator copper bulb dispenser hopper observer piston redstone lamp redstone torch repeater sticky piston

Details: how it works, measurements and properties

In depth

It unpacks shulker boxes: it places each full box from the chest at its BOXES cell, empties it into the chest at its ITEMS cell, and sends the empty box to the chest at its OUTPUT cell. Nothing is lost or duplicated: three full boxes of 64-stack items (1728 cobblestone a box) come out as every item and three empty boxes.

It moves 2.50 items per second: one box every 11 min 31.9 s; the first box arrives 11 min 32.95 s after the start.

It also handles these situations:

always-on: no lever: it runs by itself
16-stack: 16-stack items too (snowballs, ender pearls, eggs: 432 a box)
unstackable: unstackable items too (tools, armour: 27 a box)
colours: boxes keep their colour and their name
box-starved: nothing is lost while the empty-box supply runs out; it resumes when boxes come back
drop-free: box items never lie on the ground
tileable(1):

How to try it

The machine runs in the view. The view runs it without end: the chest at the cell tagged BOXES is kept full of full shulker boxes, and the chests at ITEMS and OUT are emptied as the items and the empty boxes arrive. The items are unstackable (27 fill a box). In the view the first box goes out 12.55 s after the machine starts, then one every 11.5 s. The numbers over each chest, hopper and dispenser show what it holds. Speed it up with the bar's speed dropdown (up to 100×).

It starts by itself (no lever to flip). Drag to look around, pinch or scroll to zoom.

Measurements

metric	value	what it means
boxes/min	0.087	full boxes delivered per minute, at the steady rate
items/s	2.50	items moved per second at the steady rate (from 10% to 90% of the total)
first box	11 min 32.95 s	game ticks from the start until the first box arrives
cycle	11 min 31.9 s	game ticks per box at the steady rate
hoppers awake	3	hoppers left unlocked at rest: each one looks for items every game tick (lag on busy servers)
badges	always-on, 16-stack, unstackable, colours, box-starved, drop-free, tileable(1)	the extra situations it handles (see what it does above)
bill	17 iron, 8 quartz, 33 redstone, 1 slime	what its blocks cost to craft: iron, quartz, redstone, slime

Notes from its designer

A one-block-wide shulker unloader you can line up side by side with no gap (22 blocks): a dispenser drops each full box onto a hopper that empties it, and when the box is empty a piston pushes a block into it, which breaks it into a second hopper that sends it on. How it works: as the 24-block unloader (a comparator reads the emptying hopper, a copper bulb remembers whether the box still has items, a torch fires the piston when it is empty, an observer on the piston fires the dispenser after each break, a comparator reading the dispenser starts it), with the search's savings: the pushed block is an observer that fires the dispenser itself, a lamp and a bulb stand in as the solid blocks, a piston and an observer serve as supports.

Properties

Study	Shulker box loaders and unloaders
Kind	Shulker box unloader
Blocks placed	22
Box	1×7×6 (42 blocks of space)
Made of (the blocks that change state)	comparator, copper bulb, dispenser, hopper, observer, piston, redstone lamp, redstone torch, repeater, sticky piston
Inputs / outputs	no input / OUT
Design file	`shulker-unloader-1wide-22b`

The design file

on GitHub

Design file (75 lines)

# Shulker box unloader: 2.50 items a second · 22 blocks
# https://vjeux.github.io/redstonepedia/circuits/shulker/shulker-unloader-1wide-22b.html
name: shulker-unloader-1wide-22b
circuit: shulker-unloader
tile: 1 0 0
port boxes: 0 4 0
port items: 0 -1 0
port output: 0 0 -2
origin: 0 0 -2
palette:
  A minecraft:observer[facing=up,powered=false]
  B minecraft:redstone_torch[lit=true]
  C minecraft:comparator[facing=north,mode=compare,powered=false]
  D minecraft:dispenser[facing=down,triggered=false]
  E minecraft:repeater[delay=1,facing=north,locked=false,powered=false]
  H minecraft:hopper[enabled=true,facing=down]
  O minecraft:observer[facing=down,powered=false]
  P minecraft:piston[extended=false,facing=south]
  R minecraft:redstone_lamp[lit=false]
  S minecraft:sticky_piston[extended=false,facing=north]
  W minecraft:waxed_copper_bulb[lit=false,powered=false]
  c minecraft:comparator[facing=south,mode=compare,powered=false]
  d minecraft:dispenser[facing=south,triggered=false]
  h minecraft:hopper[enabled=true,facing=north]
  o minecraft:observer[facing=north,powered=false]
  r minecraft:redstone_torch[lit=false]
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