How to build

Everything the workbench does, with its keys and gestures.

TipThe same list is one key away while you build: press ?.

Nothing on this page matches that.

Building#

In Build you place, move and change real bricks. Building needs a free account.

Tools#

Keys	What it does
`V`	Hand Move and select parts
`B`	Brick Place the hotbar part
`X`	Erase
`P`	Paint In the colour you are using
`J`	Flex Hoses and strings: start, end, then drag its handles; never through a part Choose the Flex tool (J) with a hose or string in the hand. Click where it starts and where it ends, then drag its handles to shape it.
`1–9`	Hotbar slot All nine always work. At 360 px and below the bar shows six slots and a › button for the other three
`Scroll`	Next or previous slot Over the hotbar
`Drag`	Swap two slots A slot onto another; a part from the inventory onto a slot puts it there
`E`	Inventory Every part, the model’s, recent, favourites, sub-builds
`Type in the search`	Find by connector Names, numbers and connector words: axle hole, clip, bar 3L, ball socket, Technic pin Type in the inventory’s search: a name, a number, or what it connects with (axle hole, clip, bar 3L, ball socket, Technic pin). Parts with that connector come first.
`Hover a part`	Describe a part In the inventory: its size, connectors by type, mirror twin, and a small drawing Hold the pointer over a part in the inventory (by touch, touch and hold it, then lift without dragging). The card shows its size, its connectors by type, its mirror twin and whether it is in the core catalogue, with a small drawing of its connectors.
`Fits here`	Only parts that fit In the inventory, with a connector pinned: only parts that mate with it Pin a connector on the build (with a part in the hand, click a mark). Open the inventory and choose Fits here: only the parts with a connector that mates with the pinned one are listed.
`Build from a set…`	Build from a set In the inventory: only a kit’s, an inventory’s or a parts list’s parts, with how many are left Open the inventory (E) and choose Build from a set…. Pick one of our kits, or upload an inventory (.json) or a parts list (.csv of part, colour and count). The picker shows only the set’s parts, each with how many are left, and the colour picker only its colours. Going past a count is allowed, and flagged in Checks. Agents working on the build get the same set.
`C`	Colour
`O`	Piles Tip out a bucket of parts
`L`	Bigger base

Placing and moving#

Keys	What it does
`R`	Next fit While a connector fit is shown; with one fit, turn a quarter Hold a part over a pin, hole, axle, bar or clip, or a part off the grid: a chip over it says "Fit 1 of 6". Press R (or tap Next fit) for the next way it fits, Shift+R to flip it, Tab for the next pair of connectors. Alt+scroll slides it along an axle or bar; U (or Orient) stands it on another face. Let go to place it.
`Shift`+`R`	Flip While holding a connector fit
`Tab`	Next connector pair While holding a part
`Alt`+`Scroll`	Slide Along an axle or bar
`U`	Orient Stand it on another face, of those the joint allows
`Click a connector`	Pin this connector Esc unpins it With a part in the hand, point at a small part: dots mark its connectors, coloured by kind. Click one (by touch, keep the first finger on the part and tap a mark with a second): what you hold goes on that connector wherever you point, until you place it. Esc unpins it.
`R`	Turn a quarter What you hold, the selection, or the part under the pointer
`Drag past an edge`	Hang it over It slides along the surface it is on, and stays on while a stud still holds it Drag a part towards the edge of what it sits on. It slides along the surface and stays on while a stud still holds it.
`Shift`+`R`	Turn the other way
`T`	Tip forward, onto its side Away from you; it holds where it touches
`Shift`+`T`	Tip sideways
`Alt`+`T`	Rotate by any angle About any axis, like a hinge Select a part and press Alt+T. Choose the axis and the angle, or turn it on a hinge it has.
`Shift`+`Alt`+`T`	Brick tool: upright again
`↑ ↓ ← →`	Move a stud Away, back, left, right as you look
`[` or `]`	Down, up a plate
`Alt`+`M`	Move by numbers X, Z and Y, or the six nudge buttons: for a part that is hard to grab or sits off the grid
`Drag`	Pull a part off What is clicked on top comes with it, as real bricks do; a build standing apart on the desk comes whole Drag a part: what is clicked on top of it comes with it, as real bricks come apart. Hold Alt to move just that part (and what only it holds up), or Shift to move the whole build.
`Alt`+`Drag`	Move just the part And what only it holds up
`Shift`+`Drag`	Move the whole build Down to the base
`Drag onto the desk`	Stand it on the table On the base’s stud grid, still part of the build: build on it, or drag it back into place Drag a part, or a build, off the model and let go over the bare desk. It stands on the table on the base’s stud grid and stays part of the build: put parts on it, or drag it back, a baseplate piece too.
`Ctrl`	Put it down loose Held as you let go over the bare desk: it lies there, off the grid and not part of the build Drag a part, or take one from the hotbar, over the bare desk. Hold Ctrl (⌘ on a Mac) as you let go: it lies there loose, off the grid and not part of the build. Without Ctrl it stands on the table in the build. By touch, select it, long-press and choose Put down loose. Drag a loose part onto the model to build with it.
`Alt`+`Click`	Pick a part into the hotbar
`Delete`	Remove The selection, or the part under the pointer
`Esc`	Put down, clear the selection

Selecting#

Keys	What it does
`Click`	Select A group or minifigure comes whole
`Ctrl`+`Click`	Add or take away
`Drag`	Select with a box From the bare desk; Shift+Drag adds, Ctrl+Drag adds from anywhere
`Double-click`	The whole build
`Click a figure`	Pose or dress a minifigure Pose: sit, wave, each joint · Dress: hair or hat, face, each piece’s colour Select a figure: it comes whole. Choose Pose to sit it, wave or turn each joint, or Dress to change its hair or hat, its face and the colour of each piece. Every change is one step to undo. The panel closes with its ×, with Esc, or with a click anywhere else.
`Ctrl`+`A`	Select all everything but the baseplate; again for the baseplate too
`Ctrl`+`I`	Invert
`Alt`+`1`	Same part
`Alt`+`2`	Same colour
`Alt`+`3`	Same part and colour
`Alt`+`4`	Same step

Editing#

Keys	What it does
`Ctrl`+`Z`	Undo
`Ctrl`+`Shift`+`Z` or `Ctrl`+`Y`	Redo
`Ctrl`+`X`	Cut
`Ctrl`+`C`	Copy
`Ctrl`+`V`	Paste Into your hand, to place; LDraw copied from another tab or builder pastes too
`Ctrl`+`D`	Duplicate
`Ctrl`+`G`	Group Select two or more parts (Ctrl+Click adds). Press Ctrl+G: they are picked and moved as one until you ungroup them.
`Ctrl`+`Shift`+`G`	Ungroup
`Ctrl`+`Alt`+`G`	Make a sub-build Kept by name in the inventory’s Sub-builds tab, to place again Select the parts: Ctrl+Click adds one, a box from the bare desk adds many. Press Ctrl+Alt+G (Edit › Make a sub-build). It is named and kept in the inventory’s Sub-builds tab (E). Choose it there to place another copy. Each copy moves as one, and the instructions build it once with “×2”.
`Double-click`	Edit sub-build On a copy: it opens alone, and a change there changes every copy; Esc goes back Double-click a copy (by touch, double-tap it, or long-press › Edit sub-build). It opens alone, the rest dimmed, with a breadcrumb at the top. Change it as you like, and rename it in the breadcrumb: every copy changes with it, one step to undo. Esc or Done goes back. Unlink this copy (Edit menu) keeps one copy as plain parts.
`Edit › Unlink this copy`	Unlink this copy One copy becomes plain parts
`Alt`+`X`	Mirror left to right By verified mirror twins; refused, naming the parts, where a part has none Select what to mirror. Press Alt+X: each part becomes its mirror image, by the part’s verified mirror twin (a left wing for a right one), or the twin its name gives. A part with neither is named, and nothing changes.
`Alt`+`Z`	Mirror front to back
`Alt`+`R`	Replace with the hotbar part Put the part you want in the hotbar. Select the parts to change and press Alt+R.
`Alt`+`P`	Decoration: a printed version
`Alt`+`S`	Move to step… Select parts and press Alt+S. Choose the step of the instructions they go in.

View#

Keys	What it does
`Right-drag`	Turn the camera Down to the table top, to look up under an overhang
`Middle-drag`	Pan
`Scroll`	Zoom
`W A S D`	Move the camera
`Z`	Zoom to the selection Or the whole model
`Shift`+`0`	Default view
`Shift`+`1 – 6`	Front, back, left, right, top, bottom
`Shift`+`P`	Orthographic or perspective
`H`	Hide the selection Esc or Shift+H brings it back
`Shift`+`H`	Show everything Also clears Show only this, Isolate pieces and a section cut
`I`	Show only the selection
`K`	Lock the selection
`Shift`+`K`	Unlock everything
`Alt`+`↑` or `Alt`+`↓`	See inside, a plate at a time The status chip, Esc or Shift+H shows every layer again Press Alt+↓ to cut the view down a plate, Alt+↑ to bring it back. The chip on the status line says what it would bring back and shows every layer again; so does Esc, or Shift+H.

File#

Keys	What it does
`Ctrl`+`O`	Open a model LDraw (.ldr, .mpd) or saved here
`Ctrl`+`S`	Save the model
`Ctrl`+`Shift`+`S`	Save as LDraw Sub-builds as submodels (.mpd)
`Ctrl`+`B`	Preview the instructions booklet Pages, callouts and the parts list, as printed
`Ctrl`+`Shift`+`I`	Model info

Checking#

Keys	What it does
`Ctrl`+`Shift`+`C`	Checks The problem list: overlaps, near misses, loose parts and a set’s counts, each with its fix; also from the count on the status line Press Ctrl+Shift+C, or choose the count on the status line (by touch: View › Checks in the menu). Each problem has Show, and a fix where there is one: Snap it for a near miss, Swap for one in the set for a part past its count, Show what holds it for a loose part. Check as I build and Only exact connections are switched there.

Keys

What it does

Ctrl+Shift+C

Checks
The problem list: overlaps, near misses, loose parts and a set’s counts, each with its fix; also from the count on the status line

Press Ctrl+Shift+C, or choose the count on the status line (by touch: View › Checks in the menu).
Each problem has Show, and a fix where there is one: Snap it for a near miss, Swap for one in the set for a part past its count, Show what holds it for a loose part.
Check as I build and Only exact connections are switched there.

Instructions#

Instructions plays the build step by step, as the printed booklet does.

Building instructions#

Keys	What it does
`Edit instructions`	Edit instructions Open the editor in Instructions mode or the File menu. Choose a step to split, merge, reorder or move chosen parts. Open the editor in Instructions mode or the File menu. Choose a step to split, merge, reorder or move chosen parts.
`Use this view`	Use this view Turn the camera, then use this view for the current step and later steps. As before restores inheritance; a turn icon marks large turns. Turn the camera, then use this view for the current step and later steps. As before restores inheritance; a turn icon marks large turns.
`Build on the side`	Build on the side Choose two or more parts and name the sub-assembly. Repeated assemblies appear once with a quantity. Choose two or more parts and name the sub-assembly. Repeated assemblies appear once with a quantity.
`Arrows and notes`	Arrows and notes Choose one part for a direction arrow, or add a short note. Clear them in the same panel. Choose one part for a direction arrow, or add a short note. Clear them in the same panel.
`Pages`	Pages Choose page size, orientation and steps per page. New page here starts a page; Own page reserves a page. Toggle cover, parts list and outlines. Choose page size, orientation and steps per page. New page here starts a page; Own page reserves a page. Toggle cover, parts list and outlines.
`Preview pages`	Preview pages Review the cover, step pictures, callouts and parts list. Review the cover, step pictures, callouts and parts list.
`Save as PDF`	Save as PDF Export building instructions as a PDF from the editor or preview. Export building instructions as a PDF from the editor or preview.
`Fix the order`	Fix the order Open Check for the score and problems. Fix the order moves parts after their supports where possible; inspect remaining issues. Open Check for the score and problems. Fix the order moves parts after their supports where possible; inspect remaining issues.
`Save a version`	Save a version Save edited instructions with the model. Share opens the contribution flow. Save edited instructions with the model. Share opens the contribution flow.

Playing#

Keys	What it does
`Space`	Play, pause
`←` or `→`	Step back, forward
`Home` or `End`	Start, finish
`G`	Ghost of the next parts
`Click`	What is this part? Its name, colour and step

Camera#

Keys	What it does
`Drag`	Turn the camera
`Right-drag`	Pan
`Scroll`	Zoom
`W A S D`	Move the camera
`Q` or `E`	Down, up

By touch#

On a phone or a tablet the same things are gestures.

Connector fits#

Keys	What it does
`Tap Next fit`	Next fit Hold a part over a pin, hole, axle, bar or clip, or a part off the grid: a chip over it says "Fit 1 of 6". Press R (or tap Next fit) for the next way it fits, Shift+R to flip it, Tab for the next pair of connectors. Alt+scroll slides it along an axle or bar; U (or Orient) stands it on another face. Let go to place it.
`Tap Next pair`	Next connector pair
`Tap Flip`	Flip
`Tap Slide`	Slide Enter the distance along the joint
`Tap Orient`	Orient Each tap stands it on another face the joint allows
`Tap a mark with another finger`	Pin this connector While one finger holds the part over the build; lift the first and it goes on the pinned connector With a part in the hand, point at a small part: dots mark its connectors, coloured by kind. Click one (by touch, keep the first finger on the part and tap a mark with a second): what you hold goes on that connector wherever you point, until you place it. Esc unpins it.

Building instructions#

Keys	What it does
`Tap Edit instructions`	Edit instructions Open the editor in Instructions mode or the File menu. Choose a step to split, merge, reorder or move chosen parts. Open the editor in Instructions mode or the File menu. Choose a step to split, merge, reorder or move chosen parts.
`Tap Use this view`	Use this view Turn the camera, then use this view for the current step and later steps. As before restores inheritance; a turn icon marks large turns. Turn the camera, then use this view for the current step and later steps. As before restores inheritance; a turn icon marks large turns.
`Tap Build on the side`	Build on the side Choose two or more parts and name the sub-assembly. Repeated assemblies appear once with a quantity. Choose two or more parts and name the sub-assembly. Repeated assemblies appear once with a quantity.
`Tap Arrows and notes`	Arrows and notes Choose one part for a direction arrow, or add a short note. Clear them in the same panel. Choose one part for a direction arrow, or add a short note. Clear them in the same panel.
`Tap Pages`	Pages Choose page size, orientation and steps per page. New page here starts a page; Own page reserves a page. Toggle cover, parts list and outlines. Choose page size, orientation and steps per page. New page here starts a page; Own page reserves a page. Toggle cover, parts list and outlines.
`Tap Preview pages`	Preview pages Review the cover, step pictures, callouts and parts list. Review the cover, step pictures, callouts and parts list.
`Tap Save as PDF`	Save as PDF Export building instructions as a PDF from the editor or preview. Export building instructions as a PDF from the editor or preview.
`Tap Fix the order`	Fix the order Open Check for the score and problems. Fix the order moves parts after their supports where possible; inspect remaining issues. Open Check for the score and problems. Fix the order moves parts after their supports where possible; inspect remaining issues.
`Tap Save a version`	Save a version Save edited instructions with the model. Share opens the contribution flow. Save edited instructions with the model. Share opens the contribution flow.

Connector fits#

Keys	What it does
`Tap Next fit`	Next fit Hold a part over a pin, hole, axle, bar or clip, or a part off the grid: a chip over it says "Fit 1 of 6". Press R (or tap Next fit) for the next way it fits, Shift+R to flip it, Tab for the next pair of connectors. Alt+scroll slides it along an axle or bar; U (or Orient) stands it on another face. Let go to place it.
`Tap Next pair`	Next connector pair
`Tap Flip`	Flip
`Tap Slide`	Slide Enter the distance along the joint
`Tap Orient`	Orient Each tap stands it on another face the joint allows

Camera#

Keys	What it does
`Drag`	Turn the camera One finger on the bare desk; down to the table top, to look up under an overhang
`Pinch`	Zoom
`Two-finger drag`	Pan
`Tap`	What is this part? In Instructions: its name, colour and step

Placing#

Keys	What it does
`Drag from the hotbar`	Place a part It shows just above your finger; lift to put it there
`Tap › in the hotbar`	The other hotbar slots At 360 px and below: six slots and ›; ‹ comes back
`Tap`	Place it where you tap With the Brick tool
`Touch and hold`	Aim it first With the Brick tool; lift to put it there
`Touch and hold`	Pick a part up in Parts Then drag it onto the model; a tap puts it in the hotbar
`Touch and hold, then lift`	Describe a part In Parts, without dragging: its size, connectors by type and mirror twin Hold the pointer over a part in the inventory (by touch, touch and hold it, then lift without dragging). The card shows its size, its connectors by type, its mirror twin and whether it is in the core catalogue, with a small drawing of its connectors.
`Tap ↻`	Turn it With another finger while you hold a part

Selecting and moving#

Keys	What it does
`Tap`	Select a part A group or minifigure comes whole
`Tap a figure`	Pose or dress a minifigure Pose: sit, wave, each joint · Dress: hair or hat, face, each piece’s colour Select a figure: it comes whole. Choose Pose to sit it, wave or turn each joint, or Dress to change its hair or hat, its face and the colour of each piece. Every change is one step to undo. The panel closes with its ×, with Esc, or with a click anywhere else.
`Double-tap`	The whole build
`Drag`	Pull a part off What is on top of it comes too, as real bricks come apart Drag a part: what is clicked on top of it comes with it, as real bricks come apart. Hold Alt to move just that part (and what only it holds up), or Shift to move the whole build.
`Tap, then drag`	Move just that part And what only it holds up
`Double-tap, then drag`	Move the whole build
`Drag onto the desk`	Stand it on the table On the base’s stud grid, still part of the build: build on it, or drag it back into place Drag a part, or a build, off the model and let go over the bare desk. It stands on the table on the base’s stud grid and stays part of the build: put parts on it, or drag it back, a baseplate piece too.
`Drag a hinged part`	Swing it on its hinge It clicks into the hinge’s steps and stops before it meets another part
`Long-press`	Everything you can do with it Turn, tip, mirror, copy, hide, nudge a stud at a time
`Select several`	Add parts with taps In the strip over the hotbar
`Long-press › Put down loose`	Put it down loose Off the build, lined up loose on the desk in front of it Drag a part, or take one from the hotbar, over the bare desk. Hold Ctrl (⌘ on a Mac) as you let go: it lies there loose, off the grid and not part of the build. Without Ctrl it stands on the table in the build. By touch, select it, long-press and choose Put down loose. Drag a loose part onto the model to build with it.
`Long-press › Make a sub-build`	Make a sub-build With several parts selected Select the parts: Ctrl+Click adds one, a box from the bare desk adds many. Press Ctrl+Alt+G (Edit › Make a sub-build). It is named and kept in the inventory’s Sub-builds tab (E). Choose it there to place another copy. Each copy moves as one, and the instructions build it once with “×2”.
`Double-tap a copy`	Edit sub-build Or long-press › Edit sub-build; Done goes back Double-click a copy (by touch, double-tap it, or long-press › Edit sub-build). It opens alone, the rest dimmed, with a breadcrumb at the top. Change it as you like, and rename it in the breadcrumb: every copy changes with it, one step to undo. Esc or Done goes back. Unlink this copy (Edit menu) keeps one copy as plain parts.

Editing#

Keys	What it does
`Two-finger tap`	Undo
`Three-finger tap`	Redo
`Swipe down`	Close a sheet
`Tap the selected hose`	Add a bend With the Flex tool; drag its handles to shape it

Everywhere#

Keys	What it does
`M`	Instructions or Build
`?`	These keys
`F`	Full screen
`Esc`	Close (from Instructions) In Build: put down, clear the selection, or bring back pieces hidden, isolated or cut away

Checking and history#

Keys	What it does
`Check as I build`	Live checks After each edit, without stopping your work: a count on the status line, the parts in question in red Leave Check as I build on (in Checks, Ctrl+Shift+C): each edit is checked for overlaps, near misses, loose parts and a set’s counts. The count shows on the status line and the parts in question turn red; Show selects them.
`Show`	Show a problem Select its parts
`Snap it`	Fix a near miss One step you can undo A part that almost fits but misses its studs or pin is listed as a near miss. Snap it moves it onto the nearest exact fit, as one step you can undo.
`Only exact connections`	Only exact connections In Checks: a part that would sit a little off is snapped onto the nearest exact fit, or taken back
`Swap for one in the set`	Swap for one in the set In Checks: a part past its count, in a colour the set still has
`Show what holds it`	Show what holds it In Checks: a loose part and the parts it touches
`Construction history`	Construction steps Person and agent operations; choose one to select its part Open Construction history in the Scene panel to see the operations that made this version. Choose an operation to select its part. This is separate from the building instructions.
`Test gravity`	Falling, tipping and overlaps In the Scene panel: each problem listed and marked, with the fix; choose one to select its parts Open the Scene panel and choose Test gravity. Each problem is listed with what would fix it, and its parts are marked: red where two overlap, amber where a group falls or tips. Choose one to select its parts and close in on them. The marks go with your next change.
`Gravity as I build`	Let what you change fall In the Scene panel, off until you turn it on: after each change, what it touched falls for a second while you carry on Open the Scene panel and turn on Gravity as I build. Build as usual: a moment after each change, the part of the build it touched is let fall for a second, out of your way. Nothing moves on screen. Anything that would fall or tip is listed under Test gravity and marked amber, with the fix. Your next change clears it. Builds where a change holds more than 3,000 parts together wait for the Test gravity button.
`Tidy up`	Line up loose parts In Piles: in rows in front of the model, none touching

Learning and research#

Keys	What it does
`Tutorial`	Learn the basics In the Keys menu (?): six short lessons on a practice build of their own; offered the first time you open Build Open the Keys menu (?) and choose Tutorial, or Start when Build offers it the first time. Each lesson asks for one thing on a practice build (place, turn, pull off, paint, undo, test gravity) and moves on when you have done it. Your own build is put back as it was when you leave. Leave at any time; lessons you finish are ticked off in the Keys menu.
`Share my building for research`	Research sharing In the Scene panel and your account, off until you turn it on; Keep this build out keeps one build out Open the Scene panel (or your account) and turn on Share my building for research. It is off until you do, and saying no changes nothing else. From then on the steps you take while building (each edit with its timing, searches and picks), never your name or email, help teach agents design. It shows how many of your steps have gone in. Keep this build out keeps one saved build out, whatever the switch says. Turning sharing off stops it at once.
`Why this one?`	Say why you chose Now and then after a choice, while research sharing is on: a quick pick, words if you like; at most every 20 minutes While Share my building for research is on, a card may ask "Why this one?" just after a choice: another fit for a part, a swap, taking back a part you just attached, or a colour changed after Test gravity. Pick a reason (looks better, stronger, fewer parts, matches the photo, easier to build, just trying) and add words if you like, then Send. Not now closes it. It asks at most once every 20 minutes, never while you are dragging, and never on the tutorial’s practice build. Don’t ask again stops it on this device.
`Compare`	Compare two sets On the community’s Compare page: the better design, or the one a person built Open Compare from the community page (signed in). Choose the better design of two sets. With a mouse, ← and → choose too. Each pair counts once. People’s choices give each set a Design Elo, shown on the research page.
`Briefs`	Build a brief On the community’s Briefs page: a prompt or a picture with a few rules, built by people and by agents Open Briefs from the community page. Choose Build this brief: a new build opens on the workbench, linked to the brief. Its rules (pieces, size, colours, stands up) are listed on the brief. While you build, choose Brief near the top left to show or hide the brief: its words, its picture and its rules. The workbench keeps it open or closed for that build. Agents build the same briefs over the connector (list_briefs, start_brief), so each brief gathers both kinds of build.

Community sets#

Anyone can publish a set to the community. On a published set you can:

Review it: score its part usage, proportion, surface detail and overall design from 1 to 5, and add a comment or a suggestion. Reviews need a free account; you can't review your own set, and you can change your review later.
Add a note on the workbench: open the set on the workbench, select parts, or go to a step in Instructions, and choose Add a note. The note is pinned to those parts or that step.
Remix it: make a copy in your own builds, credited to its maker.

A set's maker can mark a suggestion as taken up. Reviewers with credentials (a verified school or university email, or three or more sets published here) are shown apart, and their scores count twice in a set's combined score.

Sharing your building#

In Settings you can choose to share your building for research. It is off until you turn it on. While it is on, how you build (each edit, undo, search and pick, and when) is kept with your saved versions, and may go into a research dataset that never contains your name, username or email: a sample published openly for non-commercial research, and the full dataset licensed to research labs and companies. You can keep any build out, or turn sharing off at any time. How we handle it.