Introduction: 3x2 Locking Piston Door
This is a simple, step-by-step tutorial on how to build a 3x2 Piston door in Minecraft. This build is not only a great way to keep out the monsters, It also looks very good.
First dig out a 2 block deep 3x2 area.
Next dig out an extra 2 blocks on both sides of the hole. Make sure that only half of the new sections is 2 blocks deep (this is very important).
Now dig out a " U " shape that is 2 blocks deep.
Alright, now it's time for the redstone. Place 2 redstone repeaters on each side of the hole (shown above). Finally place 6 redstone dust in the in the design above and 2 pieces on each block the repeaters are going into.
Ok, now place two repeaters facing in to the repeaters from the last shape. Lastly fill in the rest of the " U " with redstone dust.
Now place your pistons facing inwards on top of the redstone from the last step.
Behind the pistons on both sides build a tower like shown. (redstone torch, any block, and redstone dust)
Alright, almost done. Fill in the space above the circuit and place the pressure plates on either side of the pistons.
Now place the lever to activate the locking mechanism on the circled blocks.
Finally, cover up the redstone and decorate as you please.
Congratulations you have just built yourself a locking piston door.