Manual: 1. Mine 5 blocks 2. In the 3rd block mine again once to prevent water from overflowing the lava 3. Place water in left side 4. Place lava in right side 5. Profit you can probably upgrade it and place a cart hopper under the cobblestone spawn point then a hopper below it then a chest below it to automatically catch the stones and avoid the stones from getting burnt but thats that.
Manual:
1. Mine 5 blocks
2. In the 3rd block mine again once to prevent water from overflowing the lava
3. Place water in left side
4. Place lava in right side
5. Profit
you can probably upgrade it and place a cart hopper under the cobblestone spawn point then a hopper below it then a chest below it to automatically catch the stones and avoid the stones from getting burnt but thats that.