REDSTONEPEDIA › Circuits › TNT dupers

TNT duper (runs by itself)

drops each TNT straight down to explode at one point · 30 TNT a minute · 54 blocks

Lights 30 TNT a minute while its lever is on, and every TNT falls straight down and explodes at the same point under the machine, without ever using up its own TNT block.

a push every 40 ticks (2 s) · fits in 8×5×8 + 14 blocks of air under it

on/off lever

drops each TNT straight down to explode at one pointTNT duper3D view loading (or not available in this browser)

Try it

Flip its lever (the IN button under the view) to start it: watch a lit TNT come out of the machine each cycle while its TNT block stays in place; flip it back and it stops. Press play under the view to watch a demo on a loop; touch any other control to take over.

How this design does it: Precise drop with an on/off lever, ONE clock + ONE item-free delay: tnt-precise-drop (41b) with the 52b's lever inverter holding its clock, and its release chain made long enough that each TNT is released by its OWN push: the observer watching the engine's frame starts a line of six delay-4 repeaters to the repeater the trapdoor's observer watches.

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.

Every TNT explodes 13.5 blocks under the machine, so stand it at least 14 blocks up for the blast to be in mid-air; the machine itself survives from 5 blocks up. Pour in the water where the view shows it.

Blocks used: dead tube coral fan iron trapdoor oak fence observer obsidian redstone block redstone lamp redstone torch redstone wire repeater slime block sticky piston stone tnt water

Without the on/off switch, 13 blocks smaller: TNT duper: drops each TNT straight down to explode at one point · 30 TNT a minute · 41 blocks.

Details: how it works, measurements and properties

In depth

It keeps lighting TNT forever without using up its TNT block: 30 TNT a minute. Every 2 s a piston pushes the TNT block: a piston copies every block it moves before it clears the old cells, and a TNT that gets a block update while powered at that instant is lit where it stands (a primed TNT that falls and explodes 4 s, 4 s, later) while its moved copy lands as a TNT block again. Each push lights 1 TNT.

How to try it

The duper runs by itself as soon as it is built: press play under the view to watch it. Watch the piston push the TNT block every cycle and a lit TNT (flashing white) drop out of the machine each time, while the TNT block lands again in its place; a lit TNT vanishes when its fuse runs out instead of exploding. Pause and step one game tick at a time with the bar's buttons; drag to look around, pinch or scroll to zoom.

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). Time runs left to right in game ticks (20 ticks = 1 s).

reston 1off 1on 2off 2on 3off 3on 4off 4INticks0100200300400500600700800900100011001200130014001500160017001800190020002100220023002400

Swipe the diagram sideways: the whole sequence lasts 2507 ticks (2 min 5.35 s).

Step by step (56 lines)
rest 0..200: nothing primed, standing still
on 1 200..500: 8 primed, the first 0.65 s after the lever, then 1 per 2 s
off 1 500..760: 0 primed after the lever, standing still in the rest state
on 2 760..1071: 8 primed, the first 0.65 s after the lever, then 1 per 2 s
off 2 1071..1331: 0 primed after the lever, standing still in the rest state
on 3 1331..1653: 8 primed, the first 0.65 s after the lever, then 1 per 2 s
off 3 1653..1913: 1 primed after the lever, standing still with its moving parts elsewhere than at rest
on 4 1913..2246: 8 primed, the first 1.35 s after the lever, then 1 per 2 s
off 4 2246..2506: 0 primed after the lever, standing still in the rest state
TNT 0: primed at frame 213, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 1: primed at frame 247, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 2: primed at frame 287, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 3: primed at frame 327, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 4: primed at frame 367, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 5: primed at frame 407, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 6: primed at frame 447, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 7: primed at frame 487, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 8: primed at frame 773, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 9: primed at frame 807, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 10: primed at frame 847, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 11: primed at frame 887, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 12: primed at frame 927, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 13: primed at frame 967, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 14: primed at frame 1007, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 15: primed at frame 1047, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 16: primed at frame 1344, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 17: primed at frame 1378, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 18: primed at frame 1418, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 19: primed at frame 1458, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 20: primed at frame 1498, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 21: primed at frame 1538, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 22: primed at frame 1578, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 23: primed at frame 1618, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 24: primed at frame 1658, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 25: primed at frame 1940, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 26: primed at frame 1980, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 27: primed at frame 2020, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 28: primed at frame 2060, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 29: primed at frame 2100, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 30: primed at frame 2140, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 31: primed at frame 2180, at fuse 1 at (6.5100, -17.4575, -2.8850)
TNT 32: primed at frame 2220, at fuse 1 at (6.5100, -17.4575, -2.8850)
blast at frame 292 (6.51, -18.33, -2.88): would destroy 7 blocks on open ground
blast at frame 326 (6.51, -18.33, -2.88): would destroy 7 blocks on open ground
blast at frame 366 (6.51, -18.33, -2.88): would destroy 7 blocks on open ground
blast at frame 406 (6.51, -18.33, -2.88): would destroy 7 blocks on open ground
blast at frame 446 (6.51, -18.33, -2.88): would destroy 7 blocks on open ground
blast at frame 486 (6.51, -18.33, -2.88): would destroy 7 blocks on open ground
blast at frame 526 (6.51, -18.33, -2.88): would destroy 7 blocks on open ground
blast at frame 566 (6.51, -18.33, -2.88): would destroy 7 blocks on open ground
blast at frame 852 (6.51, -18.33, -2.88): would destroy 7 blocks on open ground
blast at frame 886 (6.51, -18.33, -2.88): would destroy 7 blocks on open ground
blast at frame 926 (6.51, -18.33, -2.88): would destroy 7 blocks on open ground
blast at frame 966 (6.51, -18.33, -2.88): would destroy 7 blocks on open ground
... 33 blasts in all
useful: every blast clear of fluids, the weakest destroys 7 blocks on open ground

Measurements

metricvaluewhat it means
rate30 TNT/minlit TNT per minute
period2 sgame ticks between two pushes (the engine's cycle)
per period1TNT lit by each push
runslever on
switchlever off: stops within 0.25 s; on: restarts within 1.35 s
safe drop5 blocks
stands16 blocks above the ground (stand: in the design)
effective volume1,344 (8x8 footprint x (5 + 16) high: the box and the air under it)

Notes from its designer

Precise drop with an on/off lever, ONE clock + ONE item-free delay: tnt-precise-drop (41b) with the 52b's lever inverter holding its clock, and its release chain made long enough that each TNT is released by its OWN push: the observer watching the engine's frame starts a line of six delay-4 repeaters to the repeater the trapdoor's observer watches. A stop never strands a TNT: the last push's delayed release still comes. Not compacted yet (clk-rt's compact).

Properties

StudyTNT dupers
KindTNT duper (runs by itself)
Blocks placed54
Box8×5×8 (320 blocks of space)
Made of (the blocks that change state)dead tube coral fan, iron trapdoor, observer, redstone block, redstone lamp, redstone torch, redstone wire, repeater, slime block, sticky piston, tnt, water
Inputs / outputsIN (lever) (no output: it moves blocks)
Flagsits own lever as the input
Design filetnt-precise-drop-lever-54b

The design file

on GitHub

Design file (84 lines)
# TNT duper: drops each TNT straight down to explode at one point · 30 TNT a minute · 54 blocks
# https://vjeux.github.io/redstonepedia/circuits/tnt/tnt-precise-drop-lever-54b.html
# CIRCUIT: safe drop 5 blocks, in mid-air 13.5 blocks below the machine
name: tnt-precise-drop-lever-54b
circuit: tnt-duper
stand: 16
port input: 2 -3 -1 lever
port start: 2 -1 3 last
origin: 2 0 -4
palette:
  A minecraft:observer[facing=east,powered=false]
  B minecraft:observer[facing=north,powered=false]
  C minecraft:observer[facing=south,powered=false]
  D minecraft:dead_tube_coral_fan[waterlogged=false]
  E minecraft:observer[facing=up,powered=false]
  F minecraft:observer[facing=west,powered=false]
  G minecraft:obsidian
  H minecraft:redstone_wall_torch[facing=east,lit=true]
  I minecraft:iron_trapdoor[facing=north,half=top,open=false,powered=false,waterlogged=false]
  J minecraft:redstone_wire[east=none,north=none,power=0,south=none,west=none]
  K minecraft:repeater[delay=3,facing=west,locked=false,powered=false]
  M minecraft:sticky_piston[extended=false,facing=north]
  N minecraft:stone
  O minecraft:oak_fence[east=true,north=false,south=false,waterlogged=false,west=false]
  U minecraft:oak_fence[east=false,north=false,south=false,waterlogged=false,west=true]
  f minecraft:oak_fence[east=false,north=false,south=false,waterlogged=false,west=false]
  P minecraft:redstone_wire[east=none,north=none,power=0,south=none,west=none]
  Q minecraft:repeater[delay=4,facing=south,locked=false,powered=false]
  R minecraft:redstone_block
  S minecraft:slime_block
  T minecraft:tnt[unstable=false]
  V minecraft:repeater[delay=4,facing=west,locked=false,powered=false]
  W minecraft:water[level=0]
  X minecraft:repeater[delay=4,facing=east,locked=false,powered=false]
  Y minecraft:redstone_torch[lit=true]
  Z minecraft:lever[face=wall,facing=north,powered=false]
  o minecraft:observer[facing=down,powered=false]
  r minecraft:redstone_lamp[lit=false]
  s minecraft:sticky_piston[extended=false,facing=down]
layer -4:
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layer -3:
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layer -2:
  ...OU
  ..fW.ENN
  ...AC..N
  .......N
  Y......N
  s.SSS.NN
  B.MGS
  r...S
layer -1:
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  .....XXP
  .......Q
  .......Q
  ...T...Q
  ..D..FVP
  C..JR
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layer 0:
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  ...SS
  ....S