2.50 items a second · 36 blocks

Takes items from a chest, puts them into empty shulker boxes and sends each full box 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 · fills a box in about 11½ min · fits in 1×6×11

always on, no lever16-stack items toounstackable items tookeeps box colours and names+5 more

2.50 items a secondShulker box loader3D 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×.

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 dropper hopper observer piston redstone wire sticky piston stone

Details: how it works, measurements and properties

In depth

It packs items into shulker boxes: it takes empty shulker boxes from the chest at its BOXES cell and items from the chest at its ITEMS cell, fills each box completely, and sends it away, with everything in it, to the chest at its OUTPUT cell. Nothing is lost or duplicated and nothing is left on the ground: three boxes' worth of 64-stack items (5184 cobblestone, 1728 a box) come out as three full boxes.

It moves 2.50 items per second: one box every 11 min 32.35 s; the first box arrives 11 min 33.05 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
restart: when the items pause and come back, it carries on by itself
top-up: fills half-used boxes too
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 chests at the cells tagged ITEMS and BOXES are kept full (items, empty shulker boxes) and the one at OUT is emptied as boxes arrive. The items are unstackable (27 fill a box). In the view the first box goes out 12.65 s after the machine starts, then one every 11.85 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 33.05 s	game ticks from the start until the first box arrives
cycle	11 min 32.35 s	game ticks per box at the steady rate
hoppers awake	4	hoppers left unlocked at rest: each one looks for items every game tick (lag on busy servers)
badges	always-on, 16-stack, unstackable, colours, restart, top-up, box-starved, drop-free, tileable(1)	the extra situations it handles (see what it does above)
bill	26 iron, 14 quartz, 48 redstone, 3 slime	what its blocks cost to craft: iron, quartz, redstone, slime

Properties

Study	Shulker box loaders and unloaders
Kind	Shulker box loader
Blocks placed	36
Box	1×6×11 (66 blocks of space)
Made of (the blocks that change state)	comparator, copper bulb, dispenser, dropper, hopper, observer, piston, redstone wire, sticky piston, stone
Inputs / outputs	no input / OUT
Design file	`shulker-loader-1wide-1x6x11-36b`

The design file

on GitHub

Design file (102 lines)

# Shulker box loader: 2.50 items a second · 36 blocks
# https://vjeux.github.io/redstonepedia/circuits/shulker/shulker-loader-1wide-1x6x11-36b.html
name: shulker-loader-1wide-1x6x11-36b
circuit: shulker-loader
tile: 1 0 0
port boxes: 0 0 -2
port items: 0 2 0
port output: 0 -2 1
origin: 0 0 -4
palette:
  A minecraft:dropper[facing=down,triggered=false]
  B minecraft:dropper[facing=north,triggered=false]
  C minecraft:comparator[facing=north,mode=compare,powered=false]
  D minecraft:dispenser[facing=north,triggered=false]
  E minecraft:dropper[facing=up,triggered=false]
  F minecraft:observer[facing=south,powered=false]
  G minecraft:observer[facing=up,powered=false]
  H minecraft:hopper[enabled=true,facing=down]
  I minecraft:stone
  O minecraft:observer[facing=down,powered=false]
  P minecraft:piston[extended=false,facing=north]
  R minecraft:redstone_wire[east=side,north=side,power=0,south=side,west=side]
  S minecraft:sticky_piston[extended=false,facing=down]
  W minecraft:waxed_copper_bulb[lit=false,powered=false]
  c minecraft:comparator[facing=south,mode=compare,powered=false]
  d minecraft:dispenser[facing=up,triggered=false]
  h minecraft:hopper[enabled=true,facing=south]
  o minecraft:observer[facing=north,powered=false]
  p minecraft:piston[extended=false,facing=south]
  s minecraft:sticky_piston[extended=false,facing=up]
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