I am working on an automated chicken farm. Things are going quite well and my prototype is working, but I am having a small issue that affects my efficiency.

For my kill step, I have pistons open up a stream of water that carries the chicken to a piston smasher area. This area has a ceiling of sticky pistons which push dirt, and a floor of hoppers which collect and distribute dropped items.

My problem is that chicken meat and feathers keep popping out the top & bottom of my contraption. About 90% gets collected, but 10% ends up on the factory floor. I want to eliminate this waste.

How can I stop the items from getting pushed through my walls? Am I using the wrong block (all the non-essential blocks are dirt for easy construction)? Do I just need to make everything 2x thick? Am I missing something? Is this just how Minecraft operates?

edit I am doing this on a 1.7.4 vanilla minecraft server

edit 2 Heres an image of my killing area. I removed a wood slab so we could see inside a bit better. Note that this is the off positon, chickens aren't ready to go in yet. Directly under the dirt being pushed is a whole floor of hoppers Killing floor (closed)

  • A screenshot would be very useful.
    – NovaSword
    Jan 6, 2014 at 19:47
  • @novasword you want a screenshot from where, inside the killing floor?
    – MrGlass
    Jan 6, 2014 at 19:50
  • A screenshot of the area where the chickens are killed would be probably be good.
    – NovaSword
    Jan 6, 2014 at 19:53
  • Do you perhaps have other mods installed? Buildcraft has a pipe system and the obsidian pipe can pick up items from an area and push them somewhere you want, even in chests or directly into machines.
    – Madmenyo
    Jan 6, 2014 at 19:53
  • @novasword added 1, hope it helps
    – MrGlass
    Jan 6, 2014 at 20:01

2 Answers 2


This is essentially how Minecraft operates: when items spawn inside your crushing block, the game tries to move them somewhere valid. Any non-solid block, like slabs or stairs, that won't push items, also won't crush chickens. Double thick walls may help, but not guaranteed. The game will just try to push items harder.

The solution is to put some kind of non-full-height block above the hoppers. This way, chickens will still have their heads suffocated by a block above, but their legs and dropped items will be in a valid space above a lower block's surface. Hoppers suck items in from the whole block space above them, so that would not be a problem.

Testing indicates that the obvious choice of short block - the Slab - works perfectly.

enter image description here

Also check the list of block heights here: https://minecraft.wiki/w/Solid_block#Heights

  • Thanks, I suspect you might be right. Hdn't though of putting slabs on my pistons, I'll give that a try
    – MrGlass
    Jan 6, 2014 at 20:14
  • There's a tutorial on a nice cow machine, they use a lava blade to kill cows to get roast beef. Maybe chicken can be roasted too? They have not enough health to survive lava touch, though.
    – Orc JMR
    Jan 6, 2014 at 20:20
  • Whenever I use lava blade I seem to lose almost all dropped items to the lava. Plus, I think using a lava blade on chickens is tricky because of their height.
    – MrGlass
    Jan 6, 2014 at 20:27
  • You can also use dispensers to drop and pick up a lava source block before the chickens die resulting in cooked chicken without losing the items. Note they take about 1-2 fire ticks to die so your dispensers would have to be quick. Jan 6, 2014 at 20:40
  • Preliminary testing results: Slabs will not kill chickens, No snow to try so I skipped that. Chests cant be pushed to they don't fit into my design. Got my hands on some soul sand, and so far (1 test cycle) it seems to have worked nicely. Can you update your answer?
    – MrGlass
    Jan 6, 2014 at 21:40

Eventually I fixed this by replacing the dirt on my pistons with soul sand. Soul sand is slightly shorter than a full block (7/8s). This leaves a small space between the hoppers and the smashing blocks, so that items are not forced thorough.

  • 1
    I have to correct that Soulsand has a collision box of seven bottom eighths of a block (and is pushed as a whole), so the empty space turns out to be between the soulsand and the piston. This is irrelevant for the task at hand, though, as hoppers deal with it.
    – Orc JMR
    Jan 7, 2014 at 13:48
  • Update: I have noticed a very small chance of items getting through with this method (less than 1 per stack). It's more compact and I think it looks nicer, so I'm willing to part with that small amount of lost product.
    – MrGlass
    Jan 9, 2014 at 16:35

You must log in to answer this question.

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