Minecarts and Rails: Speed, Stations and Loops

A rail line pays for itself the first time you ride it: 8 blocks per second, hands free, no hunger drain, through a tunnel you never have to look at again. The parts are cheap and placing them takes minutes. What separates a track that flies from one that dies halfway down the tunnel is powered rail spacing — and the fact that an unpowered powered rail is not a neutral rail. It is a brake.

The four rails and what each one does

Rail — six iron ingots and one stick make sixteen. This is the only rail that can curve, and the only one you need in bulk.

Powered rail — six gold ingots, one stick and one redstone dust make six. Powered, it accelerates a cart. Unpowered, it stops one.

Detector rail — six iron ingots, one stone pressure plate and one redstone dust make six. It emits a full redstone signal for as long as a cart is sitting on it.

Activator rail — six iron ingots, two sticks and one redstone torch make six. Powered, it ejects riders from a passing cart, primes a TNT minecart, and switches a hopper minecart's pickup off. An unpowered activator rail switches that hopper minecart back on.

Two placement rules save a lot of re-digging. Only plain rail curves — powered, detector and activator rails are always straight, so every corner and junction has to be plain rail. And no rail can be curved and sloped at the same time, so turns belong on flat ground. Finish the climb, then turn.

Rails need a block with a solid top face beneath them. Hoppers count, which is what makes the unloading station further down possible.

How fast a minecart actually goes

Top speed on level powered track is 8 blocks per second. Sprinting is roughly 5.6, so a rail beats your own legs comfortably and costs you no food while it does it. Corners and climbs bleed that speed; a straight run is always faster than a scenic one.

Momentum is the part people get wrong. A cart carrying a passenger coasts a very long way on plain rail. An empty cart does not — it slows quickly and stops. A chest minecart has no passenger, so as far as physics is concerned it is an empty cart no matter how much iron is inside it. That single fact is why a cargo line needs several times more gold than the line you ride yourself.

Powered rail spacing on flat track

The pattern is always the same: one powered rail, a run of plain rails, another powered rail.

• A line only you ride. Passenger momentum carries a cart a long way, so you can leave dozens of blocks between boosters and still arrive at full speed.
• Any line that carries empty or chest carts. One powered rail every eight blocks. That spacing is safe for everything and it is what you should default to unless gold is tight.
• Starting from a standstill. Put two or three powered rails together at the station so the cart leaves at speed rather than crawling to the first booster.

To power a rail, the simplest method is a lever on the block the rail is sitting on. A redstone torch in the block directly beneath that support block does the same job and hides better in a tunnel floor, and a dust line works if you are already running one. If any of that is unfamiliar, start with redstone basics.

Where powered rails sit shoulder to shoulder, you do not need a switch on every one. A powered rail passes its signal along the track to the powered rails touching it — up to eight further in each direction — so a single lever can light an unbroken run of up to seventeen. The word unbroken is doing real work there: the signal hops from powered rail to powered rail and will not jump across plain rail, so on a line with boosters spaced eight blocks apart every booster still needs power of its own. The chain rule is for solid stretches of powered rail, which in practice means stations and slopes.

Slopes: pave the whole hill

Climbing eats momentum fast, and the wide spacing that works on the flat fails immediately on a gradient. Do not try to be economical here. Lay powered rails up the entire slope and power them — one lever covers up to seventeen consecutive rails, thanks to the chain rule above — and the cart will climb without complaint every time.

Two things to watch. Arrive at the bottom of the hill already at full speed; a booster on the flat run-up costs one gold ingot and saves you a stall. And a cart that runs out of momentum on a slope does not politely wait for you where it stopped. On plain rail, gravity drags it straight back down to the bottom of the hill, so a half-successful climb ends with your cargo at your feet again. On an unpowered powered rail it stops dead where it is. Either way the trip is over, which is the whole argument for paving the gradient properly the first time.

Descending needs nothing at all. Gravity does the work on plain rail. Put a couple of boosters at the bottom so the cart carries speed into the flat section instead of trundling.

A station that parks and launches on command

Approaching the platform, lay the track in this order: plain rails, then a detector rail, then a powered rail left switched off, then a solid block behind that rail.

1. 1.The cart rolls onto the unpowered powered rail and stops dead. That is your parking spot, and it holds the cart indefinitely.
2. 2.Flip a lever on the block under that rail and the cart launches.
3. 3.Direction is decided by the block behind it. A stationary cart on a live powered rail is pushed away from an adjacent solid block, so that one block is what sends the cart out rather than back. With no block on either side, the cart sits there doing nothing while you flip the lever repeatedly — that is the "my station is broken" bug, and it is a one-block fix.
4. 4.The detector rail earns its keep. Run its signal to a redstone lamp, an iron door or a note block so you know a cart has arrived. Feed it through a few repeaters into the launch rail instead and the station returns carts automatically after a delay.

A comparator reading a detector rail outputs a signal proportional to how full a container minecart standing on it is, so a loading station can hold a cart until it is full and only then release it. Comparators explained covers how to read that signal.

Unloading with a hopper under the track

Put a hopper directly beneath the rail the cart parks on, pointing into a chest. Rails sit on hoppers perfectly well, and a hopper pulls items straight out of a chest minecart occupying the block above it. No redstone required for the transfer itself.

Throughput is the honest limitation. A hopper moves one item every 8 game ticks — 2.5 items per second. A completely full chest minecart is 27 stacks, 1,728 items, which is roughly eleven and a half minutes through a single hopper. If that matters, send smaller loads, or let the cart creep along a run of several hoppers on plain rail instead of parking on one. Hopper mechanics goes deeper into rates and chaining.

Now the failure everybody hits. A hopper that receives redstone power is locked and will not move a single item. At this station the block under the rail is the hopper, so the usual lever-on-the-support-block trick powers the hopper and freezes it solid. Bring the launch signal in from the side at rail level, and keep every scrap of dust, every torch and every repeater away from that hopper. If a full cart is parked over a hopper and nothing is moving, that is the cause nine times out of ten. The other one: the hopper is not pointing into a container, so it fills its own five slots and jams.

Loading is the mirror image. A hopper whose output faces the block a cart is sitting in will push items into it, so a hopper above the parking rail, feeding down, fills a chest minecart for the return trip.

Chest minecart cargo lines

A chest minecart is a chest plus a minecart, twenty-seven slots, and breaking it drops the minecart, the chest and everything that was inside. It is the cheapest bulk transport in the game — but three things go wrong.

• Spacing. No passenger means poor coasting. Eight-block booster spacing, no exceptions, or you will find carts parked in the dark halfway home.
• Chunk loading. Entities do not move in unloaded chunks. Send a cargo cart down a 500-block line and it stops the instant you walk away from it. Automated cargo runs only work inside chunks that stay loaded — near where you actually are, or in the spawn chunks. For anything longer, ride alongside the cart.
• Mobs. A mob that bumps into an empty minecart climbs into it, and a mob standing on the track bleeds a cart's speed and can stall it outright. Light the tunnel properly; base lighting and mob-proofing applies to rail corridors exactly as it does to a base.

A hopper minecart is the alternative worth knowing: it collects items off the track and out of containers directly above it, and it unloads through the same hopper-under-the-rail trick. It is the standard collection system under farms where the drops are spread over a wide floor.

What a real line costs

Work it out before you start mining. A 200-block track with a booster every eight blocks is about 25 powered rails and 175 plain rails: five powered rail crafts (30 gold ingots, 5 sticks, 5 redstone) and eleven plain rail crafts (66 iron ingots). That is a serious amount of gold if you are trading for it, and the reason most players build the ride-only version first with wide spacing, then tighten it up once a gold farm is running.

Build in this order: dig the tunnel flat and lit, lay plain rail end to end, add the boosters, then build the station last. Test with an empty cart before you commit to the full booster count — an empty cart is the harshest thing your track will ever carry, and if it makes the trip, everything else will.