Sandustry Filter Guide: Allow, Block and Prevent Jams

Understand the machine's job before placing it

The Filter provides explicit material selection where gravity alone is too ambiguous. It can be configured around one solid material and used in either an allow or block plan. The rest of the layout must still give accepted and rejected pixels somewhere to move; configuration does not create output space.

Liquids and gases can pass through the structure according to the official page. That makes the Filter unsuitable as the only barrier beside Water, Steam, or another fluid. Design containment independently, then use the selection behavior for the solid stream it is meant to control.

Follow the documented input and output rules

Choose the target material and verify whether the current state allows that material or blocks it. Use the on-screen editing interface in the installed build because Update #1 improved Filter editing and key prompts can change. Send one known sample from each relevant material before trusting a mixed production feed.

Density continues to affect how pixels approach and leave the Filter. A heavier or more mobile material may settle against a different face than the diagram suggests. Contact reactions can also create a new material inside a cell, especially when a solid arrives wet. The Filter then appears incorrectly configured even though its passage is physically occupied.

Build a serviceable layout

Build a staging pocket before the Filter and two visible collection paths after it. The staging area evens out bursts and gives you a place to stop input. Keep the selected stream away from the rejected stream after separation; allowing the routes to rejoin makes a successful filter look ineffective.

Leave direct access to the building and the cells immediately around it. You should be able to clear a jam, change the target, and sample both outputs without opening the surrounding factory. Use a dedicated fluid drain when Water or another liquid accompanies the solids.

Diagnose the first failed boundary

When the wrong solid passes, pause the feed and inspect the selected material and allow or block state. Clear every cell around the Filter before retesting; an old sample trapped inside can make the first result misleading. Confirm that the source did not transform before reaching the building.

When all solids stop, inspect output clearance and material inside the structure. Remove liquid or a reacted solid from the test cell, then try one dry known sample. If liquids are the concern, remember that normal pass-through is documented behavior and add a proper fluid route rather than repeatedly changing the solid rule.

Apply the v0.5.6 version notes

Update #1 introduced better Filter editing. This page avoids hard-coding one physical key because bindings and prompts can differ, but the allow-or-block material model is documented on the current official wiki. Check the live interface after any control update.

Update #3 raises Lava density and changes several material interactions. Never use a Filter as trusted Lava containment, and retest any shared separator whose order depended on the older density. A destructive material belongs in a limited test cell before it reaches a general sorting bank.

Field facts

Troubleshooting

• Every solid stops.

  Clear the Filter cells and both outputs, verify the mode, and retry with one dry labeled sample.

• Water crosses the Filter.

  That is expected; liquids and gases pass. Add dedicated fluid containment or transport.

• The selected material reaches the wrong side.

  Confirm allow versus block, then inspect whether density, geometry, or a contact reaction changed the material before the boundary.