Dust Left Under Conveyor Belts

Dust left under conveyor belts in Moon Sweepers is a player-reported problem: a Steam reviewer wrote that dust hidden under belts often stays uncleaned even when a robot dock says the whole sector is 100% clear, and that it happens most on uneven ground such as mountains and craters, where belts snap flush with the surface. Their fix was to go back and clean those spots by hand. No patch note up to 1.0.3 mentions it, and the developers have not addressed it in the sources available here.

The practical answer has three parts. Clean the ground before you lay a belt over it. Raise belts off the ground where you can, so you, your vehicles and your robots can reach underneath. And use the Moon Map and the sector scan to find leftover dust instead of trusting a dock's completion figure near belts.

Evidence on this topic is thin. Everything below is either a direct player report, an in-game text seen on stream, or a cautious practical step you can check in your own world.

What Players Report and What Is Confirmed

Whether the game also blocks conveyors from being placed over dust is not confirmed. The "clear all dust beneath footprint" prompt appeared when players placed a Pressure Chamber, a Packager and a garage, and a player reported that a Robot Vacuum would not place while dust remained under it. Belts were laid across terrain freely in the same videos.

Why Dust Ends Up Trapped Under Belts

The likely chain, based on the reports, is simple:

1. A belt is laid across ground that still has dust on it.
2. On sloped or uneven terrain, the belt sits flush against the surface.
3. Robot vacuums, and possibly your own brush or vehicle, cannot reach the dust beneath that flush section.
4. The dock's coverage reads as finished, but the sector itself keeps a small amount of dust.

That last step matters because completion is counted per sector and region. A sector that is almost clean does not pay a completion bonus and does not count toward section achievements. Early on, finishing a hex awarded $10 in one run, and the Region Bounty upgrade adds a bonus per completed region, so a few hidden patches cost real money.

Ground-level belts cover a strip of terrain along their whole length.

Prevent It: Clean the Route Before You Lay a Belt

The cheapest fix is never to bury dust in the first place.

1. Plan the belt's path from source to destination before you build.
2. Sweep a strip along that path, a little wider than the belt, until the ground is clean.
3. Pay extra attention to slopes, crater rims and dips, where the reviewer saw the problem most.
4. Lay the belt only over ground you have already cleaned.
5. If the route must cross untouched ground, clean that part first even if the rest of the hex waits.

This is the same habit the game already enforces for machines with its footprint rule. Applying it to belts takes a few extra passes per route and avoids rebuilding later.

Raise Belts So Cleaners Can Reach Underneath

A belt that sits above the ground leaves the surface under it open. Players show this working in two ways.

• Height while building: on PC, players report Ctrl plus the mouse wheel raises or lowers a belt as you place it.
• Vehicles underneath: one streamer raised a belt specifically so they could drive under it, tested it and confirmed the vehicle passed beneath.
• Robots underneath: a short video guide on Packagers and Robot Vacuums ends with the advice to build conveyors a little higher so the robot can go under them.

Practical rules for raised belts:

• Raise the long stretches that cross open ground, especially inside a Robot Vacuum's coverage.
• Bring the belt back down only where it must meet a machine or the station intake.
• Keep the height change away from the final section before a machine. Bends and height changes right beside an input hide disconnections.
• An elevated belt passing over another belt does not join it, so raising lines also helps keep separate routes apart.

Whether a raised belt fully solves the robot problem has not been measured in the sources here. It does give every cleaner, including you, room to reach the ground.

Find the Leftover Dust

Do not rely on a dock's completion figure for sectors with belts. Check the ground directly.

• Moon Map colours: the map, opened from a station's console or with M, shows untouched ground in orange, started but unfinished ground in blue and completed ground in green. A blue sector along a belt route is a strong hint.
• Sector scan: the Field Manual lists G for scanning the sector you are standing in. Stand next to the belt and scan to see how that sector is doing.
• Walk the belt: look along both sides and under any raised spans. Thin strips of dust along edges are easy to miss, especially at night.
• Use daylight or your lamp: visibility drops in the dark. The helmet lamp is toggled with N according to the Field Manual, and lamp upgrades are available.

Check the map after a Robot Vacuum reports its area done. If a sector that the robot covered still shows blue, the leftover dust is likely near something it could not reach.

Clean Dust That Is Already Under a Belt

Once dust is trapped, you have three options, from cheapest to most expensive.

Clean around and under it by hand

The reviewer who reported the problem cleaned the spots manually. Sweep slowly along both edges of the belt with your brush, then rescan the sector. On raised sections, clean the ground directly underneath.

Raise or reroute a short section

If a flush section on a slope keeps blocking the last bit of a sector, remove just that section, clean the ground and lay it again higher or on a slightly different line. Conveyor costs $0.50 per meter, so replacing a few meters is cheap. Players report that removed structures refund about 75% of their cost, which matters little for belts but a lot for machines, so do not demolish a machine just to reach dust beside it.

Leave it for later

If the sector is far from anything that pays a bonus you need, you can note it and come back. Completion still counts toward the Moon total and section achievements, so trapped patches are worth clearing eventually, but they rarely need to interrupt a working factory.

Plan Belt Routes on Hills and Craters

The reviewer saw the problem far more on uneven terrain. When you have a choice:

• Prefer flatter ground for long belt runs, even if the route is a little longer. Extra belt is cheap.
• On unavoidable slopes, raise the belt rather than letting it hug the surface.
• Avoid running belts through the middle of a Robot Vacuum's coverage. Route them along the edge of the area, or raise them where they cross it.
• Clean a crater rim or hillside fully before building across it, then check it on the map.

Robot Vacuums and Belts in the Same Area

Robot Vacuums need a belt from their dock, so some overlap is unavoidable. The Mk I covers 19 hexes in two rings around its dock and the Mk II covers 37 hexes in three rings. The dock's output belt starts in the middle of that area.

To keep that belt from leaving dust behind:

1. Clean the dock's spot and the first stretch of the output route yourself before placing the dock.
2. Raise the output belt as soon as it leaves the dock.
3. When the dock reports its area finished, check the map for blue sectors along the belt.
4. Clean any leftovers by hand before moving on to the next dock site.

This keeps the dock's area truly finished, so you collect the completion rewards and do not have to return later.

Quick Checklist for Every New Belt

• The route was swept clean before the belt went down.
• Long stretches over open ground sit high enough for a vehicle or robot to pass under.
• The belt only drops back to ground level where it meets a machine or the station intake.
• After nearby robots finish, the Moon Map shows the sectors along the belt as green, not blue.
• A G scan next to the belt confirms the sector you are standing in is complete.

If all five hold, that belt is unlikely to leave dust behind.

What to Expect Going Forward

The developers list automation reliability and quality-of-life improvements among their priorities after 1.0.3, but nothing in the available notes targets dust under belts specifically. Until a patch says otherwise, treat it as a known player-reported issue and build around it: clean first, raise belts where cleaners need to pass, and confirm completion on the map rather than on the dock's display.