I have one lava and one water. I want to make stone factory, which is:

  • the most compact
  • the most safe to get stone from it
  • @Arda Xi, not obsidian. And not only safest, but also the most compact.
    – Nakilon
    Commented Nov 23, 2010 at 6:32
  • You can get more compact than Kevin's answer but at the cost of safety. Having a diagonal approach to the cobblestone blocks you mine will keep you from ever catching fire.
    – Sadly Not
    Commented Nov 23, 2010 at 6:57
  • 3
    I'm finding I'm collecting more than enough cobblestone from my mining activities, but I haven't started any major above ground building projects yet...
    – ChrisF
    Commented Nov 23, 2010 at 10:12
  • Sorry, you didn't specify, and lava + water = obsidian, at least.
    – user56
    Commented Nov 23, 2010 at 14:10
  • 4
    @Arda Xi: "lava source" + water = obsidian; however, any lava block that is not a source will turn into cobblestone when in contact with water. Commented Nov 24, 2010 at 1:20

3 Answers 3


To me, the most compact design would be 6x3x3. It is very simple and can be constructed from nearly anything. There is an approximate 50% yield. Here is a video of what I mean


I use the design in this post on the Minecraft forums (requires forum account). The design is also shown in this video.

You say you only have one water, but I'm sure it's not too difficult to get another. This generator allows you to mine two blocks, moving your cursor back and forth (so you're not just holding left-click for hours). The water currents will bring the dropped cobblestone towards the block on which you stand. It takes up 5x5x3 blocks of space, and if you build it in a corner of a building, you can omit the leftmost column and top row, diminishing the size to 4x4x3.

To build it, construct the following:

█████   █████   █████ │  █ - generator body (solid material)
███.█   ███W█   █████ │  W - water source
███.█   ██.▒█   ██L██ │  L - lava source
█...█   █W▒..   ███.. │  ▒ - cobblestone that is generated
████.   ███..   ███.. │  . - empty block

And the video showing it:

  • 7
    I made some adjustments to this design when I built it, to protect it from careless players . First, I built the generator body from dirt, to increase contrast with the cobblestone. Dirt is easier to find than other materials when someone digs the wall by mistake and you need to repair the generator. Secondly, the blocks directly behind the cobblestone are obsidian, to prevent careless players from holding down the button and digging out the back wall. This also lets you tape the mouse button down and go AFK with a diamond pick. Commented Dec 12, 2010 at 12:36
  • Yes, ideally the entire generator would be constructed out of obsidian.
    – Kevin Yap
    Commented Jan 11, 2011 at 22:09

On top of that, add a piston behind where the cobblestone is generated, and have it powered by redstone pulses. to do that, place 3 redstone repeaters one direction and 3 the opposite direction beside the first 3, and wire them together at the ends. now add a lever (not a button) to one side of the circuit and very quickly turn it on and off once. the piston will push out each block of cobblestone into a row of 12. you can then add pistons in a very similar design along that row, to make a square. then, if you're really adventurous and have time on your hands, put a third piston circuit at the opposite end of that square with the pistons pushing up in pulses all the time. this will create a wall which regenerates itself. cheerio.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .