reach 4 · 22 blocks

Turn the input on and a block is pushed 4 blocks out; turn it off and the block comes back exactly where it was. It goes out in 38 ticks (1.9 s) and comes back in 38 ticks (1.9 s).

Wait until the block is all the way out before flipping the lever back: turned off within 20 ticks (1 s) of being turned on, it leaves blocks stranded.

fits in 12×4×1

has its own lever

reach 4Piston extender3D view loading (or not available in this browser)

Every size 11

The best design for each size: pick one to see it.

size	blocks	numbers
reach 2	8 blocks	out in 9 ticks (0.45 s), back in 9 ticks (0.45 s)
reach 3	18 blocks	out in 27 ticks (1.35 s), back in 27 ticks (1.35 s)
reach 4 (this page)	22 blocks	out in 38 ticks (1.9 s), back in 38 ticks (1.9 s)
reach 5	31 blocks	out in 50 ticks (2.5 s), back in 55 ticks (2.75 s)
reach 6	37 blocks	out in 59 ticks (2.95 s), back in 63 ticks (3.15 s)
reach 7	44 blocks	out in 70 ticks (3.5 s), back in 76 ticks (3.8 s)
reach 8	52 blocks	out in 87 ticks (4.35 s), back in 95 ticks (4.75 s)
reach 9	59 blocks	out in 94 ticks (4.7 s), back in 104 ticks (5.2 s)
reach 10	69 blocks	out in 107 ticks (5.35 s), back in 119 ticks (5.95 s)
reach 11	75 blocks	out in 123 ticks (6.15 s), back in 135 ticks (6.75 s)
reach 12	82 blocks	out in 127 ticks (6.35 s), back in 145 ticks (7.25 s)

Try it

Flip the lever marked IN (or tap IN under the view): turn it on and watch the block go 4 blocks out; turn it off and it comes back. Press play under the view to watch a demo on a loop; touch any other control to take over.

How this design does it: Pushes a block out four cells from a one-block-wide wall, 23 blocks in a 12x4 box.

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: gold block observer repeater slime block sticky piston

Details: how it works, measurements and properties

In depth

Turning the input on pushes a block 4 cells out of the machine; turning it off brings the block back exactly where it was, with nothing left behind. A plain piston only reaches 1.

Extending takes 38 ticks (1.9 s), retracting 38 ticks (1.9 s).

How to try it

Press play under the view to watch the demo on a loop (the badge reads demo with the step it is on; the same sequence is drawn as a timing diagram below). Touch any control to stop it and try the circuit yourself.

To try it: click the lever tagged IN (or the IN button of the bar) to switch it on or off.

Inputs and output over time

The input follows this schedule (the 3D view's demo plays the same). Lime: an input is on; orange: the output is on (taller = a stronger signal, 1 to 15). Blue: where the pushed block is, 0 = home, up to N = fully out (the dashed line); it must reach N while the input is on and come all the way back. Time runs left to right in game ticks (20 ticks = 1 s).

Swipe the diagram sideways: the whole sequence lasts 2426 ticks (2 min 1.3 s).

PAYLOAD: out to N = 4 in 38 ticks (1.9 s), back in 38 ticks (1.9 s).

Step by step (5 lines)

cycle 1: extended at +38 ticks (1.9 s), restored 38 ticks (1.9 s) after the off edge
cycle 2: extended at +38 ticks (1.9 s), restored 38 ticks (1.9 s) after the off edge
cycle 3: extended at +38 ticks (1.9 s), restored 38 ticks (1.9 s) after the off edge
flip 20: on 20 ticks (1 s) then off: the rest state does not come back (left: [11, 1, 0] gold_block)
after flips: a full cycle fails

Measurements

metric	value	what it means
N	4	the reach: how many cells the block is pushed out
extend	38 ticks (1.9 s)	game ticks from switching the input on until the block is fully out
retract	38 ticks (1.9 s)	game ticks from switching the input off until the block is back
flips	breaks: off 20 ticks (1 s) after on strands blocks	what happens when the lever is flipped back before the block is all the way out: safe (nothing is stranded at any time) or the earliest flip that strands blocks

Notes from its designer

Pushes a block out four cells from a one-block-wide wall, 23 blocks in a 12x4 box.

Properties

Study	Piston extenders
Kind	Piston extender
Blocks placed	22
Box	12×4×1 (48 blocks of space)
Made of (the blocks that change state)	gold block, observer, repeater, slime block, sticky piston
Inputs / outputs	IN (lever) (no output: it moves blocks)
Flags	its own lever as the input
Design file	`pext-n4-flat-cascade23-12x4-v48-23b`

The design file

on GitHub

Design file (25 lines)

# Piston extender: reach 4 · 22 blocks
# https://vjeux.github.io/redstonepedia/circuits/pext/pext-n4-flat-cascade23-12x4-v48-23b.html
name: pext-n4-flat-cascade23-12x4-v48-23b
circuit: piston-extender 4
travel: 1 0 0
port input: 8 4 0 lever
port payload: 8 1 0
origin: 1 0 0
palette:
  A minecraft:sticky_piston[extended=false,facing=west]
  G minecraft:gold_block
  L minecraft:lever[face=wall,facing=east,powered=false]
  O minecraft:observer[facing=east,powered=false]
  R minecraft:repeater[delay=4,facing=east,locked=false,powered=false]
  S minecraft:slime_block
  o minecraft:observer[facing=up,powered=false]
  s minecraft:sticky_piston[extended=false,facing=east]
layer 1:
  sSsSsSsG
layer 2:
  .o.o.o
layer 3:
  o.o.oo..A
layer 4:
  RSO.oAOL