One of the basic devices that I build early on is a cobblestone generator, to ensure that there's plenty of cobblestone at hand.
Back in 1.8.1 with RedPower 2.0pr3 I'd come up with a vertically-oriented design for a cobble generator on a small footprint and minimal use of parts. The Redstone Tubes added in RedPower 2.0pr4 make the design cleaner and use even fewer parts, since Redstone Tubes carry the redstone signal to the block breakers.
|Side view (click to enlarge)|
|Top view (click to enlarge)|
YouTube video of the cobble generator
Each vertical layer uses two lava and four block breakers, producing four cobble. As is typical for me, I went overboard and opted for four layers, so the cobble generator produces 16 cobble per two second tick.
Here's the layout of each vertical layer of the cobble generator:
The Bill of Materials for each layer:
- 2 Lava
- 2 Redstone Tube
- 4 Block Breaker
- 8 Glass Covers (for the sides of the lava and cobble)
Additional materials required to complete the cobble generator:
- Timer (set to default two second interval)
- Various bits of wiring and tubing
- Chest(s) to store output
Just a single water source block is used for the entire generator. Note the water has a 1 block horizontal run before the vertical drops; this is critical to prevent the water from flowing horizontally inside the generator and turning the lava into obsidian. The water columns extend 1 block into the floor below the bottom level of the generator.
Each layer requires lava source blocks in order for it to flow horizontally and create the cobble. A more compact version could be built with lava source blocks above the cobble columns, but the vertical flow of lava is so slow that the generator couldn't operate on the two second cycle, so output speed would be reduced. This might be something to try in the Nether, since lava flows faster there, I think.
Each layer generates 4 cobble every 2 seconds, which works out to 120 cobble per minute per layer. This 4 layer generator produces 480 cobble per minute, which is 7.5 stacks.
An alternate layout is possible using half as much lava in a central column:
This can be used if lava is at a premium at the expense of a wider footprint and the use of more redstone tubes.
Update 11 Mar 2012: Ouroborus's comment about tilings is accurate. Here are some tilings I've worked out:
|Cobble generator tilings (click to enlarge).|
I've built the first two designs in the first column—the ones with 4 and 12 block breakers per layer. I don't think I'll go any larger; the 12-breaker design was built with six layers and it's a beast:
|Six layer cobble generator puts 72 block breakers in a 7x7 footprint (click to enlarge).|
It belches out cobble at an incredible rate. However, due to the changes in Equivalent Exchange 2 the amount of EMC is underwhelming.
This will change once Eloraam releases the Pulverizer for RedPower 2. Using Pulverizers to grind the cobble into gravel will quadruple its EMC value.