How to Anchor Parts in Roblox Studio Without Breaking Your Build

Illustration of a block explorer at the start of floating platforms leading to a finish flag.

Use Anchored when a part must stay in place under physics. If a platform drops as soon as a test starts, the two-block experiment below helps separate an anchoring problem from a collision or script problem.

Find the actual part

Stop any running test. Select the troublesome object in Explorer; if it is a Model, expand it and select the physical child Part. Filter Properties for โ€œAnchoredโ€ and enable it. Selecting a container is not the same as inspecting each surface inside it.

Robloxโ€™s parts documentation distinguishes Anchored, CanCollide and the editorโ€™s Lock control. A platform usually needs both anchoring and collision. Lock is about selection in the editor; it is not a physics repair.

Run a two-block comparison

In a separate Baseplate project, insert two unconnected blocks. Keep the floor below them. Give both blocks Size 4, 1, 4 and CanCollide = true, then set the following properties:

Two-block practice setup
Name Position X, Y, Z Anchored Expected observation
StillBlock -6, 12, 0 true Remains at the set position under gravity.
FallingBlock 6, 12, 0 false Drops toward the floor when physics begins.

Start Run to observe the blocks, then Stop. Record what you actually saw. Change only FallingBlockโ€™s Anchored value to true in edit mode and repeat. If the comparison does not match the expected observations, check for an accidental connection, a script, or the wrong selected object before drawing a conclusion.

Interpret the symptom

What moved?
Observation Next check
The whole loose platform falls. Inspect Anchored on that specific Part.
The platform stays but the character falls through. Inspect CanCollide; use the collision guide.
One decorative child drops off. Inspect that child and its intended connections.
An anchored platform moves along a deliberate path. Look for code or animation changing its transform.

An anchored object can still be repositioned deliberately by code. The checkbox does not protect a property against scripts. Make the diagnosis from the observed motion, not just from the objectโ€™s name.

Handle connected parts carefully

Welded parts can form one physical assembly. Roblox documents that anchoring one member affects the connected assembly in its assembly guide. Do not apply a stationary-floor fix to every part of a vehicle or mechanism. Compare the object with the mechanismโ€™s intended setup first.

A Model folder alone does not demonstrate that its parts have the intended physical connections. For a suspected assembly issue, isolate a copy of the smallest relevant group; avoid experimenting across your whole saved build.

Verify the repair

After the platform remains still, use a character Test and walk across it from both directions. Check the next landing too. Save only after the route works as intended. Keep a short record: object path, previous Anchored value, new value, observed motion and result of the walking check.

Continue with the four-case collision exercise or apply the result to the five-platform practice course.

Updated September 22, 2026: Replaced general advice with a two-block comparison and a symptom-based repair checklist. Official references were checked for this revision. The exercises are original practice designs, not reports of gameplay testing. Qrajo is independent of Roblox. Editorial policy ยท Report a correction.

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