Merge Parts

This article explains how to merge parts in a model hierarchy, so you can interact with a complex assembly as a single object.

Merging lets you collapse everything nested under a selected node in the hierarchy into a single object, so tools like grab and explode work on the whole sub-assembly at once rather than on individual parts. Use it to grab a component together with its fasteners — a housing, its cover, and its screws as one, instead of selecting each separately — or to collapse an entire model into a single part. The latter is especially handy for tools like probes, screwdrivers, and wrenches: once merged, using grab will pick the whole tool up as one object, with no switching between part and model grab modes. A merged node can be un-merged at any time, so nothing about the change is permanent.

Availability and requirements

Assemblies and models can be merged on PC, Mac, and iPad, and viewed on both screens and headsets. Available to all plans.

How it works

Merge works with the existing model hierarchy. Select any node, merge it, and everything nested underneath is treated as a single object. In the hierarchy, the node stops expanding to its individual sub-parts — so a sub-assembly that listed every primitive and screw gets collapsed into one clean entry.

Merged state travels with the model: when you copy and paste a model (to a same or different scene) or save it to your library, its merged parts stay merged.

Merge a node

1. Select a node in the hierarchy
2. Right-click it (long-press on iPad) and choose Merge

Everything nested under that node is now treated as a single object, and the node no longer expands to its sub-parts in the hierarchy.

Merge a full model

To turn an entire model into one part, merge at its top node. This is especially useful for tools — probes, screwdrivers, wrenches — that you want to handle as a single object.

Because the model now behaves as a model with one part, the Grab tool picks it up as a whole, so you don't have to switch the Grab tool between model and part modes as you work.

Work with a merged node

Once a node is merged, tools act on it as one object:

• Grab — picks up the entire sub-assembly together, fasteners and all
• Explode — treats the merged node as a single component
• Select — selection happens at the merged level rather than on individual sub-parts

This is what keeps a component and its hardware together — grab the housing and its screws come with it, instead of having to select the housing, the cover, and each screw on their own.

Un-merge

1. Right-click the merged node (long-press on iPad)
2. Choose Un-merge

Un-merge sits in the same spot as Merge — the menu item toggles once a node is merged. Un-merging restores the original hierarchy and all sub-parts exactly as they were; nothing is lost.

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