Cobblestone Generator in Minecraft Bedrock Edition

Overview

A cobblestone generator produces infinite cobblestone by combining lava and water. When flowing lava meets flowing water, it creates cobblestone at the point of contact. These generators are essential in skyblock worlds, void worlds, and any situation where stone is scarce. Bedrock Edition handles fluid interactions almost identically to Java, but piston-based automation has some timing differences.

How Cobblestone Generation Works

The basic principle is simple: when a lava source or flowing lava contacts flowing water (not a water source), it creates cobblestone. When flowing water contacts a lava source, it creates obsidian (which is usually undesirable for a cobblestone generator). The key is controlling which fluid flows into which to consistently produce cobblestone.

Design 1: Basic Generator

The simplest cobblestone generator for survival mode:

1. Dig a trench 1 block deep and 5 blocks long.
2. Place a water source at one end of the trench. The water flows toward the middle.
3. At the other end, place a lava source. The lava flows toward the middle.
4. Leave a 1-block gap between where the water and lava flows meet. Cobblestone generates in this gap when the flows collide.
5. Mine the cobblestone block. A new one generates immediately.

The gap between the fluids is critical. If the lava source touches water directly, you get obsidian instead of cobblestone. Experiment with the trench length until cobblestone forms reliably in the gap.

Design 2: Pillar Generator (Faster Mining)

Instead of mining cobblestone from the side, this design lets you mine from above, which is faster with an Efficiency pickaxe:

1. Build a 1-block-wide, 3-block-long trench at your feet level.
2. Place water at one end and lava at the other, with the cobblestone forming in the middle block.
3. Build walls around the generator so the fluids are contained.
4. Stand above the cobblestone generation point and mine straight down. Each block regenerates instantly when mined.
5. Use an Efficiency V pickaxe for near-instant mining speed.

Design 3: Piston-Based Automatic Generator

For bulk cobblestone production, use pistons to push generated cobblestone out and create space for new cobblestone:

1. Build the basic generator setup with water and lava creating cobblestone in a gap.
2. Place a piston facing the cobblestone generation point from the side opposite the lava.
3. Connect the piston to a repeating circuit (comparator clock or observer-based clock) that pulses every few ticks.
4. Each pulse pushes the newly generated cobblestone one block, making room for the next one.
5. After 12 pushes (the piston push limit), the row of cobblestone reaches a collection point where you can mine it or have another system process it.

Bedrock Piston Timing

In Bedrock, pistons have a 1-tick delay before extending, and the retraction is also slightly different from Java. Your clock circuit needs to account for this delay. A comparator clock with a 4-tick delay works reliably in Bedrock. Too fast a clock may cause the piston to miss cycles or break the generator.

Design 4: TNT-Based Generator

For massive cobblestone production, combine a piston generator with TNT blasting:

1. Build a piston generator that pushes a 12-block row of cobblestone.
2. At the end of the row, place TNT that is triggered when the row reaches full length.
3. The TNT blasts the cobblestone into dropped items, which are collected by hoppers below.
4. This produces cobblestone as items rather than blocks, filling chests automatically.

Troubleshooting

• Getting obsidian instead of cobblestone: The water is reaching the lava source block. Add more distance between the source blocks or use signs to stop water flow at the correct point.
• Stone instead of cobblestone: If flowing lava meets a water source block, it creates stone. Ensure the lava contacts flowing water, not a source block.
• Lava disappearing: If water overwrites the lava source, you lose it permanently. Always protect the lava source with blocks on all sides except the flow direction.
• Piston not firing: Check your redstone clock circuit. Bedrock piston timing requires slightly longer pulse intervals than Java.

Skyblock Applications

Cobblestone generators are the primary block source in skyblock worlds. Start with the basic design and upgrade to a piston generator as you acquire redstone. The cobblestone can be smelted into stone or further crafted into tools, furnaces, and building materials.

Java vs Bedrock Differences

• Fluid mechanics for cobblestone generation are virtually identical between editions.
• Piston timing differences in Bedrock require adjusting clock circuits. Use slightly slower clocks than Java designs recommend.
• TNT behavior and blast radius are the same between editions.
• Hopper collection speed is the same (1 item per 8 ticks).

FAQ

Can I make a smooth stone generator?

Yes. If flowing lava contacts a water source block, it creates stone instead of cobblestone. Adjust the generator so the lava flow touches a water source. However, this is harder to automate.

How fast can I mine with an Efficiency V pickaxe?

With Efficiency V and Haste II (from a beacon), cobblestone breaks almost instantly. You can mine as fast as you can click, limited only by the generation speed.

Is the lava consumed?

No. Only the flowing lava creates cobblestone. The lava source block is never consumed, providing infinite cobblestone production.

For the Java cobblestone generator guide, see the Java Cobblestone Generator Guide on guide.astroworldmc.com.