Why Splitters Matter

An alchemy factory splitter matters because a belt network only stays useful when every output has somewhere to go. Whether you need an even three-way division or need to separate one item from a mixed line, the layout must keep moving on both sides.

The current 1.0 reference advises using the live build menu, device tooltip, and production display as the authority for exact behavior. Official 1.0 notes do not provide a complete specification table for every automation component, so verify details in your own current build before committing to a large rebuild.

Community discussion identifies two practical splitter approaches: creating a three-way belt split for even distribution, or using a filter splitter to route a selected item away from everything else.

Splitter approachReported purposeMain caution
Three-way splitDivide one line of goods evenly among three outputsPlacement order can matter
Branch or manifold layoutFeed machines along a branching lineEach later branch receives less of the original flow
Filter splitterSeparate one selected item from mixed outputsA blocked output can stop the entire splitter

A simple branch layout can still be useful. One community explanation describes the first machine receiving half the goods, the second receiving a quarter, and the third receiving an eighth. That is different from a three-way split, which was described as handling the distribution evenly.

Before rebuilding an entire factory, test a small belt section with storage at the outputs. This makes it easier to see whether the issue is the splitter setup, its orientation, or a blocked destination.

Building an Even Three-Way Split

A player discussion confirms that a three-way split is possible. The reported placement method is to place the middle belt first, optionally place one side, and then place the other belt starting from the middle belt.

This can feel unintuitive because belts may show a directional arrow during placement without producing the intended final connection. If the placement preview appears correct but the completed belt does not change direction, remove the guesswork by rebuilding the small junction in the reported order.

Build stepReported actionWhy it helps
1Place the middle beltEstablishes the central connection
2Optionally place one side beltCreates part of the junction
3Place the remaining belt starting from the middle beltCompletes the reported three-way arrangement
4Test the outputsConfirms that all three paths receive goods

Use a three-way layout when the goal is to distribute a single supply line evenly rather than feed a row of machines in sequence. The community source specifically contrasts it with a straight branch path, where the earlier machine takes the largest share.

A manifold can be a workable alternative when an even split is unnecessary. It may also be easier to place if you are still learning belt behavior. However, a manifold does not produce the same reported distribution pattern as a three-way split.

When troubleshooting a three-way setup, check these points:

  • Start the final side-belt placement from the middle belt.
  • Watch the completed connection, not only the placement arrow.
  • Confirm that all receiving belts are attached and have open space ahead.
  • Test with actual goods before extending the line to machines.
  • Use a small temporary layout first if a larger production line is already active.

The goal is not merely to make three belts touch. The goal is to create a junction that actually routes goods into all three intended paths.

Filtering Mixed Belt Outputs

A filter splitter is designed to separate one specific item from a mixed output belt. You select the filtered item in the splitter menu; that item exits through the highlighted output, while all other items continue through the remaining output.

Community guides refer to the highlighted filtered exit as the yellow output or yellow port. One source says the other output is blue, while another calls it the normal port. The important shared point is that one route is reserved for the selected item and the other handles everything else.

Filter splitter behaviorWhat the sources report
Item selectionChoose one item in the splitter menu
Filtered routeThe selected item exits through the highlighted output
Other routeAll non-selected items use the remaining output
Output blockageIf either side backs up, the whole splitter can stop
OrientationThe highlighted output may be vertical or horizontal depending on orientation

The most frequently described example is mixed rotten-log output. Community guides say this process produces mushrooms and planks together. Mushrooms are routed toward an assembler for advanced fertilizer, while planks need a separate destination such as fuel use, another production chain, storage, or disposal.

Treat specific unlock, recipe, and production-value claims in older guides carefully. The current 1.0 reference explicitly warns that older walkthroughs and databases should be treated as historical context unless a current primary source confirms the detail.

A practical mixed-output layout follows this pattern:

StageRouteIntended result
Mixed output sourceSend output onto a beltCarry both item types
Filter splitterSelect the item to isolateSeparate the selected item
Filtered outputSend selected item to its destinationKeep the desired production chain supplied
Remaining outputSend all other items to a consumer, buffer, or disposalPrevent a belt backup
End of lineAdd a safe destination for overflowKeep both splitter outputs moving

The non-filtered output deserves as much attention as the filtered one. If planks fill their destination and stop moving, mushrooms can stop as well. A clean-looking filtered line is not enough if the leftover line has nowhere to go.

Possible destinations reported by community guides include:

  • Furnaces for fuel.
  • Quicklime or plant-ash chains.
  • A storage box used as a buffer.
  • A trash can for overflow or disposal.

Do not send both outputs back into the same belt if the goal is to maintain separation. One guide specifically recommends avoiding that arrangement. Keep the routes distinct until each item reaches a purpose-built destination.

Keeping Splitter Lines Moving

Most splitter failures are flow failures, not selection failures. A correctly configured filter splitter can still halt when one output belt is full, a storage box reaches capacity, or a machine downstream stops consuming its assigned item.

The safest habit is to design each output for the worst case: assume the destination may pause, then provide a buffer, a consumer, or a disposal route. This is especially important for byproducts, because they are easy to ignore until they block the item you actually need.

SymptomLikely cause described in guidesPractical response
Splitter stops after running normallyOne output is backed upCheck both output belts and destinations
Filtered item does not leave through the expected routeNo item was selected, or orientation is wrongCheck the splitter menu and direction
Top or vertical output is hard to accessSplitter orientation creates a vertical portRotate it and provide access as needed
Mixed line jamsLeftover item has no destinationConsume, buffer, or discard the byproduct
Three-way split will not formBelt placement order is wrongStart with the middle belt and build outward

One community guide says to use T to rotate the splitter. Confirm that control in your current build before relying on it, because the 1.0 reference recommends checking live interface behavior.

Testing with storage boxes is useful because it reveals which output stops first. Put a temporary storage box at each outlet, run a small amount of material through the junction, and inspect whether both lines remain active. Once the routing is proven, replace temporary storage with the machines, fuel chains, or disposal routes your factory needs.

A splitter line should be reviewed after changes downstream. Adding a new machine, changing a production route, or filling a storage buffer can alter the behavior of an upstream belt. If a line that previously worked suddenly freezes, inspect the outputs before rebuilding the splitter itself.

FAQ

QuestionAnswer
Is a three-way split possible?Yes. A community discussion reports that it can be built by placing the middle belt first, then building the remaining connection from that middle belt.
Why does my filter splitter stop?Community guides consistently report that either blocked output can stop the whole splitter. Check both routes, not only the filtered route.
What does the highlighted output do?It is the filtered route for the item selected in the splitter menu. Everything else uses the remaining output.
Should I use a manifold instead?A manifold can work, but it does not provide the even distribution reported for a three-way split.
How should I verify an alchemy factory splitter in 1.0?Check the current build menu, device tooltip, and live production display, then test the layout with open output storage.

For an alchemy factory splitter, the key rule is simple: every output needs a clear destination. Build three-way junctions in the reported placement order, select the filtered item deliberately, and keep both sides of a filter splitter moving.