Tutorials/Mechanisms

Mechanisms are complex systems of blocks used to perform certain tasks, such as opening a door from afar or revealing a hidden staircase. These systems are built from simple components and normally involve some kind of user input, like breaking a torch, which generates some kind of result, like a door being revealed. Mechanisms can range from simple switches that open and close doors from a safe distance, to complex devices such as combination locks that prevent intruders from entering your fort.

This page is a work in progress, so feel free to add your own components and mechanisms as you build and the game develops. Pictures are encouraged, but not required.

Components
These are the basic, modular parts which can be combined to form any complex mechanism. Please note that individual items in the game are not considered components.

Physical Components

 * Sand Switch (Also known as Airlocks)
 * Sand placed above a torch will not fall until the torch is broken. This can be used to control water flow above the user or cause torches connected to the falling sand to break.


 * Pit
 * Pit into which sand or water may fall.


 * Reservoir
 * Natural or user-made lake which stores water to be used in a mechanism.


 * Water Channel
 * A channel in which water can flow. Often used to break torches, causing things to fall


 * Tube
 * A long three by three structure that can be used for launching TNT or shockwaves

Electrical Components
See Crafting and Redstone circuits for these components and Advanced Electronic Mechanisms for more complicated electronic mechanisms.

Mechanisms
Useful devices made from the combination of components.

Standard Mechanisms
To make a simple automatic door, place a pressure plate on the floor on the inside of the door, remembering that doors swing inward. Now, whenever you approach the door from the outside, you can open the door and it will automatically close behind you when you pass through it. When approaching the door from the inside, it will open the door in front of you and will automatically close it behind you. This is great for making one-way doors that mobs can enter but not exit, or exit but not enter, depending on the set up. This will only work on right-handed doors; left handed doors have a glitch where they will invert the input and stay perpetually open with this method.
 * Airlock
 * Automatic Doors

Hidden Mechanisms

 * Traps


 * Hidden Door
 * Simple hidden opening revealed by breaking a torch.
 * Make a sand switch which opens a reservoir allowing water to flow down a short channel to a pit. The pit allows the water to drop below floor level and break torches supporting a sand wall above a pit. When the sand wall falls, an opening is revealed.




 * Picture Door
 * Larger pictures can be placed in front of doors and physically hides their presence. The pictures can be broken by hitting them or throwing snowballs, etc.


 * Hidden Floor Staircase
 * Hidden staircase in the floor revealed by breaking a torch.
 * Make an inverted sand or gravel staircase in the floor of a room(one block wide), supported by torches. Make a water channel or water channels adjacent to the torches so that when they are filled, the torches break and the stairs will fall. (IMPORTANT: make sure that that the sand or gravel will cover the water hole after it falls to avoid flooding) Make a sand switch which opens a reservoir allowing water to flow down a short channel to a pit. The pit allows the water to drop beneath the floor and run to the torches holding the staircase.


 * Hidden Ceiling Staircase
 * Hidden staircase in the ceiling of a room
 * Make a gravel or sand staircase in the ceiling of a room supported by torches connected to blocks of sand supported by more torches. Make a channel run next to the lower torches and back to a reservoir. Make a sand switch that can open the reservoir. When the torch in the sand switch is broken, water should flow down the channel breaking the first set of torches causing the sand to fall. The sand would both close off the channel to negate flooding and break the torches attached to it, causing the staircase to fall.
 * Example of one 'step' and the reservoir system

%%%%%%%%%%%%%%%%%%%% %%+%%%%%%%%%% %%             %%+%%%%%%%%%%+ ~ %%  %%+%%%%%%%%O + ~ %% %%^+%%%%%%%%%+%%%%%% %% ^O%%%%%%%%+%%%%%% %% %%%%%%%%%%+%%%%%% %           %+%%%%%%                   %           %+%%%%%%                   %            ^%%%%%%                    %           % %%%%%%                   %%%%%%%%%%%%%%%%%%%%


 * % = Stone
 * + = Sand
 * ~ = Water
 * ^ = Torch
 * O = Channel running 'into the page'


 * Assuming the two channels in this picture are connected, when the torch near the floor level is broken water from the resivour will flow to the other torchs and drop the 'step' down to the floor. other sequential steps can be added to make a staircase.


 * Hidden Sand Stairs
 * Look at it properly to understand.
 * hidden sand stairs.jpg

Electronic Mechanisms

 * Combination Lock
 * A door which is opened by using levers to input a certain combination. The levers are wired to an "AND" gate, with hidden redstone circuitry to open the metal door. Once inside, a lever is placed next to the metal door to close it behind you. A step-by-step tutorial on how to build one can be found here.


 * Item Activated Door
 * A door that only opens when an item is dropped into a pit of water.
 * Make three-deep a pit near an iron door. Build a level channel away from the base of the pit. Place a wood pressure plate in the channel no more than 8 blocks from the base of the pit. Wire the plate to the door (not through the channel). You will have to run the wire back up to the surface, or very nearly so, but it can be concealed under well-placed walls. Cover the channel and place a block of water at the top of the pit, allowing water to flow down the channel. Any item thrown in the pit should flow down to the plate and cause the wire to activate, thus opening the door.


 * Flashing Indicator Light
 * A blinking red torch activated when a pressure plate is stepped on. Can be used to tell if mobs are sneaking through your caves.
 * Make a pressure plate wired to the input of a red torch. Wire the output of the first torch to the input of a new red torch. Run the output of the new torch to its own input, creating a blinking loop. Wire the output of the new torch to the input of any other torch to carry the blinking effect.
 * Example:




 * The loop on the right will flicker on and off when the plate is stepped on.

Warning: This burns out quickly if a single torch is used, so take this fact in mind.


 * Multiple torches hooked up:




 * Sound could be added to make an alarm by wiring note blocks to the flashing torches.


 * Block Destruction as a Trigger
 * It is possible for an electronic output to be generated as a result of a block being destroyed. To achieve this, place a Redstone Torch on the side of a block facing away from you. Next, set up an inverter between the block and your mechanism. When the block is destroyed, the torch will fall, the lack of input will be inverted, and the mechanism will activate. This can be used to make traps, as shown in this video.

The bottom torch powers the block above it, powering it and all redstone torches attached to the block. Each level (block with torch on top) acts like it's own repeater. This also can go upward until the map ends while still producing power. If you want to dispose of this quickly or are making experiments just use Gravel or Sand for the block type.
 * Redstone Tower

The glass allows the redstone current to pass through while the other moveable blocks do not. This can be used to operate doors, bridges, ect. The best part is you can use multiple buttons and make doors that open from both sides using the same circuit. The tutorial can be viewed here. There are also images with pistons.
 * GlassSwitch


 * 2 Wire Control
 * With a lot repeater and AND-gates it is possible to control multiple outputs with only 2 wires. It can be very tricky to get the timing right. You need a pulse generators in both wires to get a pulse with a defined length and in most cases the output pulse needs to be made longer. As shown in this video you have a top wire and a bottom wire with repeater. On one side you have repeater between the buttons on the top wire and none (or as needed) in the bottom wire. At the other side none (or as needed) on the top wire and matching repeater (to the others top side) on the bottom one. between which you place AND-gates (matching the buttons). The Idea is that the signals only meet at one AND gate at the same time.
 * Videotutorial: watch
 * Example use:

Piston Doors
Piston doors can be as easy as 2 sticky pistons attached to blocks that move inwards revealing a 2x1 passage way, or as complicated as the one seen in the original piston revealer that mojang released. (as seen here http://www.youtube.com/watch?v=uZJr86d2IUo&feature=feedu )



More complicated Redstone circuit mechanisms are on Tutorial/Advanced Electronic Mechanisms.

Piston Elevators
Although making an elevator with pistons in 1.7 is extremely difficult, this can be overcome by creating a spiral staircase of pistons that propels the user upwards very fast. These elevators also work as a dumb waiter, any block or item that is placed or dropped on the first piston will be pushed all the way to the top. Please note that a pulse limiter is needed to make the pistons properly extend and retract.

How to make your very own elevator!!!

Launcher Pads
A launchpad is similar in design to a TNT cannon, but instead of launching horizontally, it launches vertically either straight up or at an angle, depending on the design. There are many ways to create them, but some methods are more efficient than others. For instance, a simple design would be the cross pattern, as shown below.

This is what it would look like from above:

S S @~%~@ S%S %%&%% S%S @~%~@  S S


 * ~ = Water
 * S = Water source block
 * @ = Building block
 * % = Building block with Redstone on top
 * & = Building block with pressure pad on top

The above design can easily be expanded in size and improved, but it is one of the easiest designs so far. Another simple design, yet much more powerful,is here:

Pulsers
A sealed tube with a water source at the back with three levers on each side and three TNT placed in the tube in the water flow created by the water block that propels the tnt blast across a short or wide area, determined by the TNT. For example:

Top: OOOOOOOO OOOOO OOOOOOOO

Top:(inside) OOOOOOOO TTTWSOOO OOOOOOOO

Bottom: OOOOOOOO OOOOOOOO OOOOOOOO

Left Side: OOOOOOOO OOOOOLLL OOOOOOOO

Right Side: OOOOOOOO LLLOOOOO OOOOOOOO

L=Lever O=any TNT-proof block you want.(I Used Obsidian) W=Water S= Water Source T=TNT

WARNING: The Shockwave goes in all directions but doesn't destroy any blocks, only mobs. (killed a sheep in one shot) close up it takes about 2 hearts away. I load it from above. DO NOT PRESS ALL THREE LEVERS AT ONCE!!

I will experiment to see different designs and i will get back to you on them.

Cannons
A cannon is a mechanism that can be used to launch TNT that explodes, making it a powerful weapon against mobs, terrain or any other object in the game that can be damaged by explosions.

Basic Components
A cannon is made using two sets of TNT: The Charge and the Shot.

The Charge is used to propel the Shot, which can be projected when it has been struck and is timing down the fuse. (The Shot must already be flashing white when the Charge detonates.) Both the Charge and the Shot can be made up of any number of blocks of TNT, with the following effects:

Charge - Larger amounts of TNT will propel a Shot further.

Shot - Larger amounts of TNT will cause more damage on impact.

This is all that is required for a cannon, but most people build other additions onto the cannon to make them function more efficiently.

Further Components
Cannon designs commonly include the following:

> 1. Fuse wires and switches - The fuse wires allow the cannon to be fired at the press of two buttons (one activating the Charge and the other activating the Shot), making the firing process much more efficient and allowing for a larger Charge to be used.

> 2. A trough full of water - This contains the blast and prevents damage to the surrounding environment. It also has the added benefit of pushing the Charge towards the end of the barrel, allowing you to use the most of the charge possible.

> 3. Shot mounting block - Some cannons have a block or half block at the end of the water trough so the Shot can travel slightly upwards when its launched, allowing it to travel farther.

Building materials
Most people choose to make cannons out of stone or cobblestone due to its availability, but you can make it out of any solid (preferably gravity resistant) block, such as Dirt, Wood or even Diamond. The best choices for material are most likely Cobblestone or Dirt, due to their availability. You can use TNT resistant Obsidian to make a 'dry cannon' which doesn't require water to remain intact between shots, but it is extremely difficult to correct problems if you place a block wrong in the construction phase unless you use creative mode, then it is incredibly easy.

Video tutorials
One Button Cannon (A cannon where you only have to press 1 button):

Cannon sizes
Cannons can range from one or two block constructions to truly massive super structures, boasting larger Charges, Shots and some special features, including multi timed projectiles, multiple shots or even a semi-automatic fire function. A cannon can be designed to any size with varying functionality. Smaller cannons normally are less effective than larger cannons as they will have less Charge and Shot blocks, which results in far less power. Another type of cannon is possible with pistons. With one button press, it will fire repeatedly, the actual number depending on the cannon size. The first time this was achieved without hacks,glitches and bug exploitation, was by player SirBananas. His model is called the Piston Spider Cannon.

Cannon Glitch
There is a glitch with cannons that makes them fire about twice as far in the f=0 and f=3 directions than they do in the f=1 and f=2 directions. Keep this in mind when making cannons. Here is a video demonstrating the glitch:

Shot Mounting Blocks
Shot mounting blocks are placed right under the shot charge and affect their flight angle and forward velocity when fired. When a TNT Shot is activated, it will fall and land on the mounting block, which elevates it above the water trough. Various blocks can be used and give different shot trajectories. The following are ones tested and deemed safe. Some blocks, such as a pressure plate, can result in the castrophic failure of the cannon when used as shot mounting blocks.

Generally, the higher the Shot is elevated by the mounting block, the higher the angle of fire but the lower the velocity. Switching mounting blocks on a cannon will give it more options on range and trajectory.

Pros: Highest velocity, simple, scalable
 * No Mounting Block

Cons: poor range in smaller cannons, downward trajectory, line-of-sight only

When no mounting block is used, the Shot is either allow to fall onto the water trough or is place on the trough directly. the Shot will fire out completely horizontal, or 0°. Gravity will quickly pulled the Shot to the ground, giving a very flat, downwards trajectory.

With small TNT charges, the range can be extremely limited. To increase the range, ever larger charges are needed or the cannon must be built higher above the ground. A larger charge means a higher velocity to the Shot, pushing the Shot farther away before it drops to the the ground.

Players have been known to use up to 70 TNT charges and beyond. But economically, a cannon without a mounting block will take more TNT and longer to load for a certain range.


 * Single Block

Pros: Higher firing angle, can "lobe" shots

Cons: Low velocity, reduced power and extremely poor range for smaller cannons

A single full size block such as cobblestone or obsidian is placed under the Shot. This has the effect of elevating the Shot above the water trough, so the blast force from the Charge is applied not just forward, but upwards. The shot is fired out at a high angle and trajectory. This is useful for hitting a elevated target, or one behind terrain or obstruction.

However, part of the blast force is absorbed by a solid mounting block, so the cannon will suffer similar problems of needing large charge sizes. Also, since some of the energy is expelled in the upwards direction, forward shot velocity is reduced greatly.

A better alternative to the single mounting block is using a Ladder instead.


 * Half Block

Pros: Smooth trajectory (not too high, not too low), average velocity, more efficient for small and medium cannons 

Cons: Slightly reduced power, not best for either straight OR lobe shots, fuse range limit * 

A half block is the compromise between a single block and no mounting, and generally more efficient than either. More of a cannon's blast force is directed forward, but there is still an upward vector that raises the angle of fire to roughly 30°. As with a single block, some of the blast energy is absorbed by the block, but much less. From the same TNT load, the half block has greater range than a single block or no block.

When the TNT Shot is initially placed over a half block, it will hang over the half block as if it was a full size block. Once the TNT has been "primed", it will fall down and sit on the true height of the half block.

The firing angle produced by a half block is good for extending the range of a cannon and hitting elevated targets, but its too low for effective lobing over high walls and obstacles. For straight direct firing, shots fired with a half block mounting generally land level on the ground within a certain range. However, due to the limited fuse time of TNT in the game, scaling up the TNT charges up to a point will result in the shot flying too high and exploding in the air before it lands or reach the cannon's maximum range. This will be refer to as the "fuse range limit * ". All cannons are limited by the fuse range limit, but cannons firing at higher angles are especially prone to the fuse limit, as the shot velocity is lower and shots reach higher altitudes.


 * Trap Door

Pros: (closed) Optimized for flat trajectory, velocity almost the same as no-block, (opened) can be used in open position for higher firing angle, good scaling

Cons: Be sure that priming circuit doesn't activate the trapdoor by accident.

If the firing angle of the half block is too high for your purpose, a closed Trapdoor can be used instead. Like the half block, it provides some upward force to the shot by elevating it above the trough. A trapdoor, however, is only half the height of a half block. Firing angle is roughly 15-20°, making it extremely effective for straight shots at very long range (+180 block).

Little forward velocity is lost when firing, and shot typically fly out at very high speeds. This combine with the low firing angle means cannons firing larger loads can extend their range without encountering too much fuse range problems as with the half block or ladder mounting.

As Trapdoors flip upwards when opened, they can be used to support the Shot the same way as a Ladder mount. Trapdoors can hence be used in both both a low angle and high angle firing mode.



NOTE: Be sure that your priming circuit for the Shot doesn't activate the trapdoor, or open/closed the Trapdoor beforehand.


 * Ladder

Pros: Efficent with small and medium cannons, High firing angle, parabolic trajectory, good for lobing shots and high alititude

Cons: Low velocity, poor scaling, limited range at ±120 blocks

A Ladder placed on the side can serve as a very effective mounting block for firing at high angles and lobing shots. A primed Shot will be supported by the edge thickness of the ladder, preventing it from falling into the trough. Because a Ladder is not a full size block, none of the energy from the blast is absorbed, and the shot is propelled out at full force. By adding ladders above each other, different firing angles can be achieved. Typically, a single ladder will give an angle just higher than a half block, roughly 40°-45°. Two ladders will give an extremely parabolic flight, shots fly out at about 50°-60°.

A good portion of the blast energy directed upwards on the block, so shot velocities are generally much slower than a no-mount or half block mount cannon. In return, a cannon have no problem lobing shots over terrain and walls. At larger charge loads, shots can reach very high alititudes.

However, this also means the fuse range limit is a inherent problem with this mounting. Within a 100 block distance, well built cannons level with the ground can expect to land shots low enough to cause damage. But beyond this shots explode midair way beforehand, even with a shot primed at maximum fuse time with a delay circuit. Hence, one can't simply add more TNT to increase the range, as it will only make the shot fly higher. A basic solution is to put the cannon below ground, in a dugged pit with a slanted slope to allow the shot to fly out. Since the shot had a lower starting point, it will explode closer to the ground once its fuse time runs out. To reach ranges beyond 150 blocks, this solution becomes impractical.



A TNT "mortar" using a ladder mounting block.

Trivia

 * Cannons can also be used as a transport system, as it can launch humans, however this is not recommended. Even if you survive the actual launch, you might not survive the fall.


 * These devices can be made to launch mobs for pure enjoyment.


 * It is also possible to launch sand and gravel, these will create a pile at the landing spot, useful for testing cannon range.


 * Cannons are ineffective against water based defenses.

Anti-Grief Sensors
The following are circuits designed to prevent changes to your structures without the use of Admin Powers.

Wall Protections
There are multiple ways of protecting a wall. Firstly being the easiest which is to protect the bottom of a two high wall, players going through it would break both and ergo the bottom as well, this trips the circuit giving you a positive redstone curcuit.



(X) stands for a floor / wall of any material that redstone can be placed on. (-) stands for redstone. Below is a 2D cut of a piece of the wall. The principle of it is that when the lower block is broken the circuit is then connected.

XXXX XXXX X X-- X-XX XXXX

Door Protection
Iron doors are good and strong, however their ability to be broken is their major problem. One of the best ways of avoiding this is as follows.

To avoid the problem with a torch being placed to open the door easily place an iron door in a position so that its ON state blocks the entrance, then by powering it from beneath, you can stop it from being opened.

To then avoid someone breaking the door, place a block of water above it, then another torch a block away behind the door. When the door is broken, the water falls down and breaks the torch, giving you a negative which can be used.

X stands for ground. w stands for water. I stands for torch. - stands for wire

XwXXXXX | | I--- XXXXXXX

Also, instead of water, try lava.

However, due to the slowness of lava (and water), it may be beneficial to make a sand or gravel block drop, dislodging a piece of wiring or a torch.

Liquid redirection technology
Redstone circuits can be used to redirect the flow of Lava or Water in the following manner:

These systems can be useful in many complicated mechanisms, or simply for aesthetic value.

Light Sensor
As detailed in http://www.minecraftforum.net/viewtopic.php?f=1020&t=165642, flowers and mushrooms can be used to make light sensors.

Block Updates
See Tutorials/Block update detector.

Bank System
After the 1.5 update came out, it became much easier to make stations, banks and other minecart related buildings with the use of powered rails. As you can see on the video example, you can choose from either a empty minecart or a Storage minecart from the two buttons. Also in the video you get a glimpse of how it was made.

This is an updated, better, expandable bank system. This video also has an older bank system showing how to make one without using powered rails.

This is a simple bank system using powered rails, which should be helpful for Minecrafters less experienced with redstone.

Making items travel upwards
Using this system you can use pistons to throw items upwards. Then the water catches the items, and pushes them a little forward, then the items are pushed by the water to another pistons. And it repeats.

Note: This system uses the piston mod. The normal pistons do not throw items in this way.

Also See

 * Redstone Torch
 * Redstone circuits
 * Traps

Anleitungen/Mechanismen Tutoriels/Mécanismes