Cobblestone farming is the technique of using a cobblestone generator to produce cobblestone without damaging the terrain. Cobblestone generators work on the principle that when a lava stream comes into contact with water, the lava is turned into cobblestone. This fresh cobblestone then prevents the two streams from touching. When this fresh cobblestone is removed, the two fluids will produce another piece of cobblestone.
Many generator designs exist, but the most basic is a 10-block long trench with a water source block at one end, and a lava source block at the other. This will create cobblestone next to the lava source block.
One must be careful not to accidentally create obsidian, which happens when water comes into contact with a lava source block (See Tutorials/Obsidian Farming). A basic understanding of fluids is helpful to prevent this.
Why Build a Cobblestone Generator?
While the popularity of building any form of cobblestone generator varies, there are many reasons why a player could build a cobblestone generator.
Here's a list of the most common reasons:
- A close proximity to a cobblestone generator would save time traveling from your shelter to the nearest mine.
- Building a cobblestone generator will avoid ruining the integrity of a cave or underground shelter.
- Some Survival Multiplayer Servers tend to have a big demand for cobblestone.
- Custom maps or challenge maps sometimes require a cobblestone generator in order to progress.
- If a large amount of Cobblestone is needed.
- Superflat maps tend to be extremely low on resources.
- Wanting a self-repairing object (e.g. wall, floor, pillar).
- For decoration.
Video
Cobblestone generator/video
Standard (Pistonless) Cobblestone Generator
Standard generators have been around for quite a while. Their popularity, however, is limited because cobblestone is so readily available. Standard generators require the player to mine and collect the fresh cobblestone in proximity to the lava. This both presents risks to the player, and reduces efficiency if the dropped item is destroyed by the lava. These drawbacks may be mitigated by design choices, for example by removing the block under the cobblestone, allowing the loot to fall in a safe place.
Best Examples of Standard Cobblestone Generators:
A lava stream touching a water stream is the simplest type of generator.
A balanced unit that is expandable, for multiplayer use. The water stream carries cobblestone loot towards the player, making it marginally more efficient.
Using obsidian blocks behind the lava source blocks will stop you from accidentally mining a hole in the back wall.
This design features a lower chance of the cobblestone being destroyed by lava, but it is significantly larger.
Piston Cobblestone Generator
Pistons can be used to automate the cobblestone generator and reduce the amount of cobblestone lost. Piston cobblestone generators work on the same principle as standard generators, but, rather than mining, a piston pushes the fresh cobblestone or stone out of the way, allowing the streams to touch once again. Piston cobblestone generators can be used both to create a large supply of cobblestone that the player can mine later, or to supply a self-repairing structure with blocks.
Best Examples of the Piston Cobblestone Generator:
A redstone clock drives a piston which pushes out the generated cobblestone.
In this design there is a circuit to detect when a block has been formed, which makes the piston move.
This generator design consistently produces four cobblestone blocks on every fourth piston cycle. The blocks are pushed upwards, negating any chance of the cobblestone burning from touching lava.
Components of a Piston Generator
There are three basic components to consider in a piston cobblestone generator:
- The Core. This part includes the water and lava that creates the fresh cobblestone.
- A clock generator or block detector. While not mandatory for all piston-based cobblestone generators, this part generates a signal to drive the piston that pushes fresh cobblestone out.
- Secondary Pistons. While optional, additional pistons may be used to move the fresh cobblestone farther, allowing for more cobblestone to be generated between mining operations. Secondary pistons may also be used to move the blocks into self-repairing structures.
The Core
Stone-generating core surrounded by glass.
Cobblestone-generating core surrounded by glass.
The piston pushing the stone/cobblestone is always non-sticky.
The core serves the same function as a standard cobblestone generator. Lava and water mix in front of the piston, forming a cobblestone block. One thing to consider is that the piston must be accessible by redstone. There is a hole at the end of the water stream which draws the water straight. When attached to a redstone clock, this will create a single row of cobblestone 13 blocks long (since the limit a piston can push blocks is 14 blocks).
Smooth stone generators are rarely designed without pistons, as lava needs to be directly above the stone generated. Lava must flow down into flowing water in front of the piston. As with cobblestone generators, a single-piston design can only make a row of stone up to 13 blocks long.
Redstone Clock Generator
Simple redstone pulse-generating clock. Repeater delays are 3-3-3.
A basic understanding of redstone is helpful but not necessarily required.
The ideal clock will send a pulse shortly after the stone/cobblestone has been created, making way for a new piece of stone/cobblestone. The generator can be toggled by placing a lever on the side of the block with the redstone torch.
To create a simple clock, place a redstone torch onto the side of a block, and a piece of redstone dust on the opposite side. Then place a diode on top of the block, pointed toward the dust, and set it to maximum delay. Place solid blocks above the torch and dust. The connection to the piston(s) can branch off the redstone torch or dust. Powering the block above the dust, e.g. with a lever, will disable the clock.
Sample side view of the clock required for a generator:
l x - d - x r - x - y x - x - x (Ground)
x: a covering block such as dirt or stone d: a diode/repeater r: redstone torch y: redstone dust l: lever
note: the dashes do not represent spacings
Secondary Pistons
Since pistons can only push a maximum of 12 blocks, the core will only produce a limit of 13 cobblestone blocks. This can be greatly increased with secondary pistons that guide the row of cobblestone in other directions. In a way, it is a similar idea as the core piston in that it removes the fresh cobblestone in order for more to be created. Self repairing structures tend to use several secondary pistons and one or two cores.
Triggering a secondary piston can be done a few ways. The secondary pistons can be connected to the same redstone clock as the core, which periodically extend the piston. This can be annoying if you are working in the area as pistons make considerable noise. Alternatively, a Redstone Repeater can send a signal through the block which detects when a piece of cobblestone is present. This can then send a signal to a line of secondary pistons which trigger simultaneously.
Best Examples of Secondary Piston Usage:
An example of secondary pistons used to rebuild a damaged wall.
An example of secondary pistons used to rebuild a damaged floor.
Smooth Stone generator
As of 1.9, lava flowing into water from above creates smooth stone. Stone can be mined slightly faster than cobblestone, and it can also be collected as stone using a pickaxe with the Silk Touch enchantment. Using smooth stone also gives self-repairing structures a different, more natural look.
Best Examples of a Smooth Stone Generator:
As it is faster to mine, it can be more time efficient to use a smooth stone generator over a cobblestone one.
A basic smooth stone generator that can be expanded to have multiple outlets, for multiplayer use.
A design that prevents the water source block from turning into cobblestone, a common issue with smooth stone generators.
A small and reliable smooth stone generator that can be turned on and off by switch.
More Video Tutorials/Examples
This design is the easiest to build and the most basic. It is simply lava and water placed in the ground with a place to mine the cobble from.
Self-Repairing Fast Smooth-stone Generator Tutorial. It is automatic, repairing, very fast and effective.
This design offers a completely covered and compact version of a cobblestone farm. This design's size should minimize possible lag and includes a switch, to control production.
This design is a very efficient cobble generator, doesn't lag your game, is very small, and fairly easy to build. Unlike others, this version has a built-in failsafe, so it never breaks.
This uses a four sided repeater clock, but with uneven delay. The piston is retracted 5/6th of the cycle.
This compact design triggers when cobblestone is generated rather than using an external clock which means it provides the player fresh cobblestone much faster.
This Generator is the version for Smooth Stone without clock for enhanced speed and reduced lag. (Smooth Stone can be mined faster, too)
This shows how secondary pistons move the row of cobblestone from the core. They trigger at every clock cycle.
This shows how signals can go through solid blocks using repeaters. This will trigger independently of a central clock and is a viable way of setting up secondary pistons to minimize noise.
This generator uses no redstone and is quite efficient. It works using the 'tight' spacing block on the fence to let the cobblestone fall, while keeping you up.