I made a fast minecart-with-hopper unloader, intended for high-efficiency, extensive farms.

The proof of concept works - it unloads the minecart at 35 items per second, and the "core" is beautifully compact and quite trivial - using a "buffer" minecart with hopper. Instead of unloading the minecart with hopper directly into a hopper, I unload it into another minecart with hopper - this process is incredibly fast, and so the stop can be very short, then the first minecart returns to making its rounds collecting goodies along the track, while a normal hopper unloads the "buffer minecart" into a chest or other destination.

enter image description here

Problems begin with the "easy" part: stop the minecart for a moment for unloading and then start it again. My solution with repeaters and piston is ugly and expensive. It adds only 1s delay (20 ticks), unloading exactly 35 items.

enter image description here

Since checking the minecart contents without unloading it fully is not so easy, a longer delay would be nice - but not as nice as making this smaller (narrower!) and cheaper - as this is to be used with high-efficiency farms, it should be as narrow as possible to be tileable over multiple "instances" - and cheap to implement these multiple instances.

Can you help me make this more compact and cheaper without losing the speed?

  • To meet the requirements of smaller, cheaper, and more delay, you have posted a challenge. I have built 3 different versions. None of which are cheaper. Two are just reworks of your solution. One only 2 wide, and one is a single wide tileable. Delay isn't much more and more expensive. I have a 3rd working version which is 2 wide and gives a delay of about 5 to 8 seconds. Let me know if you want to post them as an answer and include pictures. I didn't post as an answer as none of them meet all three requirements.
    – IronAnvil
    Commented May 23, 2017 at 18:19
  • @IronAnvil: In the meanwhile, I made one more fault-proof, although even bigger and more expensive. The piston pushes the cart sideways, onto a second track, that way there's no collision with "oncoming traffic" and the sensor isn't triggered twice. This thing is quite incredibly efficient (emptying the "buffer" being the bottleneck) so I don't think it needs to be this narrow and cheap.
    – SF.
    Commented May 23, 2017 at 23:43
  • So what would your new requirements be? Better control of the delay timer? A modified pulse fired ethos timer would be my suggestion. If you don't care about delay being configurable, a dropper delay is a cheap alternative.
    – IronAnvil
    Commented May 24, 2017 at 17:20
  • @IronAnvil: probably 1. making it fault-proof, so that two carts in short sequence are serviced right - currently a second car will totally mess it up. 2. still making it moderately compact. The timer I used was some 40 or so repeaters in line. 1. is achievable through a 'spider web separator' - a vertical shaft ending with a spider web, carts stack on top of each other, and drop only after passing through the web, roughly 20s apart. But this becomes an awfully tall tower. So, price is no longer such a priority but getting the size in check and making it entirely fault-proof would be great.
    – SF.
    Commented May 25, 2017 at 23:19
  • BTW, dropper delay = 5 minutes... the purpose of this unloader is to be FAST - it's ~20s to unload 5 stacks. So timing control is pretty important.
    – SF.
    Commented May 25, 2017 at 23:22

1 Answer 1


Okay, I got something built that works nicely, here's how I built it.

First start with this start

Then remove the block with the rail on it, and add the required blocks to get here

first image Note: the piston is temporary, and normal

Then fire the piston to push the slab into the minecart hopper, then remove it and add the rails. second image note: the detector rail must be on a slope, and can't be replaced with another type of rail

Add the required redstone, and you're done! final build Note: you can replace the redstone torch with a block of redstone under the rail, or a lever, and if you replace the redstone dust with a repeater they can be placed side-by-side

Just run a minecart with hopper (or chest) in through the powered rail, and it will unload into the hopper below


You must log in to answer this question.

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