Fix SketchUp Dynamic Component Scale Bug When Copying

SketchUp Dynamic Components are powerful — until you copy one and watch everything break. The scale attribute crash is one of the most persistent bugs in SketchUp, still reproducible in SketchUp 2026: copy a Dynamic Component with Move + Ctrl (or paste from clipboard), try to scale it, and the child objects freeze at the original parent’s dimensions — or worse, collapse to zero. The root cause is attribute inheritance: child objects inside a copied Dynamic Component continue reading parameters from the original parent’s definition rather than the new instance. The values in the Component Options dialog turn red, the geometry refuses to respond, and no amount of re-entering numbers fixes it unless you force a formula re-evaluation. Groups inside Dynamic Components make this dramatically worse. Unlike Components, Groups do not carry their own definition copy, so when you nest a Group inside a Dynamic Component and copy that parent, the Group’s attributes stay hard-linked to the original. Renaming the Group does not sever that link — only converting it to a Component before adding formulas will give it a clean, independent attribute copy that survives duplication. A second, lesser-known trigger is that SketchUp only fires a formula recalculation when you interact with the Scale tool directly on that instance. A copy made without triggering the Scale tool is never asked to recalculate, so its children hold the parent’s hard-coded dimensions indefinitely. This is why right-clicking and choosing Scale Definition, or nudging any value in Component Options, sometimes appears to “magically” repair a copy — it manually fires the recalc the copy never received.

Pro Tips

• Author with Components, never Groups, inside any DC that will be copied. This is the single most effective way to avoid the scale bug entirely. Every element that will carry a formula — width, height, position offset, visibility — must be a Component instance with its own definition. Groups look convenient because they do not create a new definition entry in the Components panel, but that convenience is exactly what causes the attribute leak when you copy the parent. The rule of thumb: if an object inside a DC has an _scale_tool_used or dimension formula, it must be a Component.
• Use Make Unique before editing a copy you want to diverge. If you copy a Dynamic Component and then want to give that copy different attribute values from the original, right-click it and choose Make Unique before changing anything in Component Options. Without Make Unique, both instances share the same definition — editing one changes the other. More importantly, Make Unique gives the copy its own definition copy, which is what SketchUp re-evaluates against once a recalculation is triggered (via the Scale tool or Scale Definition).
• Right-click → Scale Definition as a quick diagnostic. Right-clicking a Dynamic Component and choosing Scale Definition forces SketchUp to resize the definition bounding box to fit the current geometry. This often clears a visual scale mismatch on its own. If Scale Definition fixes the visual but Component Options still shows red values, the attribute formulas still need a manual recalculation — nudge a value in Component Options and undo it, as described below.
• Nudge Component Options values to force a recalc manually. Open Component Options for the broken copy, find any numeric attribute, increment it by a small amount (e.g., add 0.001 to the width), press Enter, then undo the change. That sequence triggers SketchUp’s formula evaluator for that instance. It is fiddly and unreliable for complex DCs with many children, but it works for simple two- or three-attribute components.
• Check _scale_tool_used when building DCs for distribution. SketchUp writes a hidden attribute _scale_tool_used to a component instance when the user scales it with the Scale tool. Some DC formulas read this flag to decide whether to recompute. If your formula chain depends on this flag but the end-user copies instead of scales, the flag is never set and the chain never fires. Design formulas that do not gate on _scale_tool_used, or explicitly set it in your copy-paste workflow before distributing the file.

System Requirements

• SketchUp version: SketchUp 2022 or newer (2022, 2023, 2024, 2025, 2026)
• Operating system: Windows 10/11 or macOS 12 Monterey and newer
• Dynamic Components extension: Must be enabled in SketchUp (included by default; check Extension Manager if Component Options is missing from the Window menu)

Nguyen Huu Khanh

Architect turned developer