Groups and components

Groups and components are how a model grows past a handful of boxes without becoming unmanageable. Both are organizational: they never merge geometry (that’s what booleans are for).

Groups

A group bundles objects (and other groups — they nest) into one selectable, movable unit.

• Create: select two or more things and choose Object ▸ Group (⌘G / Ctrl+G), or click Group on the contextual dock.
• Dissolve: select a group and choose Object ▸ Ungroup (⇧⌘G / Ctrl+Shift+G); the members return to being independent, unchanged.
• Edit the contents: double-click the group (or click Edit on the contextual dock). You’re now inside it: the rest of the scene dims, the Outliner marks the open group “editing”, and the breadcrumb reads Model → the group’s name → …. Every tool works on the members from here, not just selection and drawing — Push/Pull, Follow Me, Union/Subtract/Intersect between two members, Slice, and Move/Rotate/Scale on an individual member, the same set that works inside a component (below). Anything you create while you’re in there — a new group, a component instance, an imported model, 3D text — becomes a member when you step out. Press Esc, or double-click empty space, to step back out one level.

Groups nest, and editing follows the nesting: double-click a member group to open it too, one more level on the breadcrumb, one more Esc to leave. A component instance inside a group opens for editing the ordinary way — double-click it — once you’ve drilled in through the group to reach it.

Moving, rotating, or scaling a group transforms everything inside it together, and Move with the copy modifier tapped (Option on Mac, Ctrl on Windows/Linux) copies the whole group — nested groups, names, tags, and materials included — as a linked copy, or as a plain independent one on the second tap; component instances inside come along as new instances of the same definition (Move). Groups also work as boolean operands: Union, Subtract, and Intersect accept a group anywhere they accept a solid (Combining solids). Hiding a group (the eye toggle in the Outliner) hides all of its contents. Groups are also handy purely as selection sets — a group’s name in the Outliner and Object Info makes big models legible.

Delete everything inside an open group and step out, and the group goes with it — undo brings it all back, same as a component left with nothing (below).

Adding to an existing group

Two ways to move something into a group after the fact, without disturbing its geometry:

• Drag it in the Outliner. Drag a row — or your whole current selection, if the row you grab is part of it — onto a group’s row to add it there, or onto the Model row at the top to pull it back out to the top level. A group can’t be dropped into itself or into one of its own members.
• Cut, edit the group, Paste In Place. Select the thing, ⌘X/Ctrl+X to cut it, double-click the group to open it, then ⇧⌘V/Ctrl+Shift+V to paste it back at its original position. Step out and it’s a member, right where it was.

Either way it’s pure reorganizing — the object itself, and everywhere else it might be referenced, is untouched.

Linked copies

Copy a board with Move, Rotate, or Paste and the copy is linked to the original: they share one shape, so a change to one shows up on every copy. Push a leg’s face and all four legs get longer. The other copies stay on screen the whole time and follow along as you work, and there is nothing to switch on first. You edit the copy you are looking at.

A linked copy keeps what makes it a copy: its own position, rotation, and name. It does not need a name of its own. A row in the Outliner shows the copy’s own name if you gave it one, otherwise the shared name, otherwise the name of the board itself. Select a copy and Object Info shows Linked copies: 4, with two name fields: Name (all copies) renames every copy, and This copy names just the one.

What you can do with a linked copy, from the Object menu, the contextual dock, Object Info, or the Copies menu on its Outliner row:

• Unlink makes this one copy independent. It keeps its name, tags, and shape, and the others stay linked to each other.
• Unlink all makes every copy independent at once. One undo puts the whole set back.
• Make component turns the set into a named component: it asks for a name, the link icon goes away, and the other copies follow it as copies of the new component. Saving a linked copy to the Library does this first, because a Library item needs a name.
• Select all copies selects every copy in the set, in the viewport and the Outliner together.

Nothing splits behind your back. If a command can’t keep copies linked, Hew tells you what it did: a Union or Intersect with a linked copy unlinks it first and says “Unlinked 2 copies to join them”.

How a linked copy differs from a component. A component is a part you named and meant to reuse: it has a name, a place in the Components panel, and a Library entry. A linked copy is what you get when you copy something: no name required, no panel entry, and no new word to learn. If a set of linked copies turns out to be a part you want to keep, Make component promotes it. The reverse never happens; a component doesn’t turn back into linked copies.

Link identical copies

Boards you drew one at a time are separate objects even when they are the same shape. Edit ▸ Link identical copies finds loose objects that are the same shape, or mirror images of each other, and turns them into one set of linked copies. Select two or more objects to limit it to those; with nothing selected it looks at the whole model. A mirror image becomes a mirrored copy of the first board.

Each copy keeps its own position, name, tags, and paint. The first board’s shape is the one they all share, so if the others had paint on individual faces, Hew says so: “Linked 4 copies; paint on the faces of 2 copies was dropped”. It also tells you when a copy’s own axes were replaced by the first board’s. One undo puts every board back. Hew never does this on its own; Model Health shows a “look-alike objects can be linked” notice with a Link identical copies button when it finds some.

Components

A component is shared geometry: one definition, any number of placed instances. Every instance has its own position, rotation, scale, and mirroring, but they all reference the same shape. Model one screw, place it eight times; fix the thread once, all eight update.

• Create a definition: select one or more objects, groups, or component instances and choose Object ▸ Make Component, or click Make Component on the contextual dock. The selection becomes the definition’s members — a selected group stays whole, and a selected instance nests its definition inside the new one (Nesting) — and what you had selected is replaced by the first instance.
• Place more instances: select an instance and choose Object ▸ Place Copy; the new instance lands just beside the original, ready to Move into position. Or Move an instance with copy mode on (tap Option on Mac, Ctrl on Windows/Linux) to drop copies where you want them — and type x5 right after a copy to place a whole row (Move). Copy and Paste (⌘C/⌘V, Ctrl+C/Ctrl+V, or Paste In Place) do the same thing within a model: the pasted instance is another placement of the same definition, so editing either one edits both. That holds for a cut-and-paste too, and for a selection that mixes instances with plain objects — the objects paste as independent copies, the instances stay linked. Pasting into a different model (another window) brings the definition along as a new one there; pasting the same copy into that model again reuses it rather than adding another. If you want a pasted copy to be its own thing, paste it and then use Make Unique (Breaking the link).
• Edit the definition: double-click any instance. The copy you opened is yours to edit, and every other placement of the component stays right where it is, faded like the rest of the model, showing each change as you make it — push a face and every copy’s face moves, and while you’re still dragging, the preview of the pull shows on every copy too, so you can watch the whole row take shape before you click. Move, Rotate, Scale, and Offset preview the same way. The members themselves behave exactly like ordinary top-level geometry. Every tool works on them, not just Push/Pull and Paint: draw new geometry (on a member’s face, or on any plane — press an arrow key to lock it, exactly like drawing at the top level), Push/Pull, Follow Me, Union/Subtract/Intersect between two members, Slice, and Move/Rotate/Scale on an individual member. Anything you draw while you’re in there becomes part of the component too. Step out (Esc, or double-click outside the component) and every placement is back to full strength with the change in it, wherever it’s placed, however it’s rotated, scaled, or mirrored — there’s only one shape underneath. The tools reach the open component’s faces through whatever is in front of them, in Shaded or X-ray, so you can Push/Pull a face buried inside a box without moving the box out of the way. X-ray is not needed for this.

An instance that’s scaled unevenly on one axis, or placed inside a group you haven’t opened, edits a little differently, because that placement can’t be lifted out to edit alone. Everything — the tools, drawing, stepping out, the other copies following along — works the same, with one exception: a definition edited this way always needs at least one member, so deleting its last one is refused rather than emptying the component.

Deleting a member otherwise works the same way you’d delete anything else. Delete every member and step out, and the whole component — and every instance of it — disappears with it (undo brings it all back). The one exception is a component that sits inside another component: it stays, empty, because removing it would change the component around it.

Saving works normally while you’re in the middle of editing a component, autosave included — your place in the edit holds, and the saved file reflects the component as it stands.

Construction guides (Tape Measure, Protractor) stay ground-truthed to the world even while you’re inside a group or component — a guide dropped there won’t follow the member around. Use guides at the top level, or on an exploded copy, when you need them for a component’s own shape. The Tape Measure’s resize gesture is the exception: measure and type a new length while a group or component is open, and it offers to resize just that container instead of the whole model (Precision, measurement, and guides).

Names and tags

A component keeps the identity of what you made it from. If the object was named “The Box” and tagged Objects/Boxes, the new component’s definition name is “The Box” and the first instance carries the tag. An unnamed selection gets a generated name (“Component 1”, “Component 2”, …).

The definition name is what every instance displays — place six copies of “The Box” and the Outliner shows six rows all named “The Box”, which is how you can tell they’re the same component. Two name fields in Object Info control this:

• Definition Name renames the component itself; every instance updates at once.
• Instance Name labels just this placement. The Outliner then shows it as “Instance Name (Definition Name)” — “Front Door (Door)” — so the relationship stays visible.

Object Info also counts the siblings: a selected instance’s Type reads “Component (6 instances)”, and clicking the count selects all six, in the viewport and the Outliner together.

Breaking the link

For a linked copy, Unlink and Unlink all do this job: Unlink makes the selected copy independent, and Unlink all makes every copy independent in one step.

For a component, two commands take an instance out of the shared-definition world, both available on the contextual dock when an instance is selected:

• Make Unique detaches this instance into its own new definition. Use it when one screw needs to be different from its siblings. The new component keeps the name “Screw”, since it is still the same part until you rename it — unless the instance had its own name, which becomes the new definition’s name. The pieces inside keep their names and tags, so a board you copied is still called “Leg” after Make Unique.
• Explode bakes the instance down into ordinary, independent geometry in place. The definition (and other instances) are unaffected.

Components panel

Expand Components in the right-hand tray (or View ▸ Components, ⇧⌘M / Ctrl+Shift+M) to see every component definition in the document, one row per definition, with a small thumbnail of its geometry and its live instance count alongside.

• Type into the filter box above the list to narrow it to definitions whose name matches — handy once a model has dozens of them. Clearing the filter shows everything again; it never changes what’s selected in the model.
• Click a row to select every instance of that definition, in the viewport and the Outliner together — the same thing clicking Object Info’s instance count does, but for a definition you haven’t picked an instance of yet.
• Double-click a row’s name (or click the pencil next to it) to rename the definition in place — the same rename Object Info’s Definition Name field does.
• Click the × next to a row to delete the definition. One with no instances disappears immediately. One that’s still placed somewhere asks first — “Delete definition and its N instances?” — since deleting a definition takes every instance of it with it. Either way it’s a single undoable step.

Purge Unused, in the panel header, deletes every component definition with no instances anywhere AND every palette material nothing paints, in one step. It shows you what it’s about to remove — names and counts — before you confirm. The same action is available from File ▸ Purge Unused… when the panel itself isn’t open.

In the Outliner

Groups appear as folders you can expand; component instances get their own hexagon icon. A linked copy gets a link icon instead, and a ×4 badge showing how many copies share its shape (a set with only one copy left has no badge and reads as an ordinary board). Hover the badge to highlight the other copies. Hover the row and a small Copies menu offers Unlink, Unlink all, Make component, Select all copies, and Rename; renaming a row changes the copy’s own name if it has one, and the shared name otherwise. Double-clicking a row in the Outliner opens every level between the top and that row in one step — group, nested group, instance, whatever the chain is — landing in the same state you’d reach clicking through the viewport one level at a time, with each level on the breadcrumb marked “editing”. The breadcrumb at the top of the Outliner shows where you are and offers one-click exits.

Hover a group row for its second eye button — a stacked-eye glyph — to hide or show every one of its members at once, nested groups included; the root Model row above the tree has the same button for the whole document. Typing into the filter field above the tree narrows the list to matching rows and the groups standing between them and the top.

What did I just click?

A click in the viewport selects the outermost group a thing belongs to, so a click on a cabinet door inside a kitchen group selects the kitchen. The selection path, the strip at the top of the viewport, tells you what was under that click: Model › Kitchen › Base Cabinets › Cabinet 2 › Door. The selected level is highlighted; the levels after it run down to the thing you hit.

Click any crumb to select that level instead: Cabinet 2 to move the one cabinet, Door to rename it. Nothing opens and nothing fades. The Outliner expands to the row, and Object Info names it with an “in Kitchen › Base Cabinets › Cabinet 2” line under its type; the group names there are clickable too, except one you are editing, which stays plain text. Double-click a crumb to open that group for editing, the same as double-clicking its Outliner row. While you are editing, the strip marks each open level “editing”, and clicking Model closes them all.

With the Select tool, rest the cursor on anything for a moment and the inference tip names it under the snap: On Face, then Door · in Cabinet 2. A part of a component you haven’t opened appears at the end of the path in italics; double-click the component’s crumb to open it.

The strip shows only when there is a path to show. One object with no group around it shows nothing, and so does a selection of several things.

Nesting

A component definition can contain other components (and groups) as members, the same way it contains objects — place a wheel component inside a car component, and the car definition holds four wheel instances alongside its own geometry. Make Component builds this from a selection that includes instances: a selected group stays whole rather than being flattened, and a selected instance becomes a nested member instead of being refused.

Editing drills down the same way it does for groups. Double-click a component to open it; inside, a nested component instance is an ordinary instance, so double-clicking it opens it too, one more level on the breadcrumb. Esc steps back out one level at a time, the same order you drilled in. Placing a new instance while you’re editing another — from the Library, or with Make Component on something you just drew — folds that instance into the definition you’re editing once you step out. That’s the everyday way an assembly gets built: open the car, place a wheel four times, step out.

A definition can’t contain itself, directly or through some chain of nested definitions, and nesting is bounded to 64 levels deep — both refused outright rather than silently truncated.

Explode and Make Unique treat nesting differently. Exploding an assembly surfaces its nested components as ordinary instances in the right place, each sharing geometry with its own definition. Make Unique only copies one level: the copy’s own nested instances share their inner definitions with the original, the same as SketchUp.

To see which way a component is turned, switch on View ▸ Part Axes: a red, green, and blue triad marks the selected or open component’s own axes.