Formboard

Formboard mode turns the Layout view into a 1:1 physical scale drawing of your harness. The lengths you see on the canvas correspond directly to real-world measurements.

When formboard mode is on, the layout view changes to support physical assembly: snapping to grid is removed, bundles bend with a real corner radius, and bundles can be set to their actual lengths.

Turning on Formboard Mode

Open Main Menu → Harness settings → Formboard.
Turn on Use formboard for layout.

The layout view immediately re-renders at 1:1 scale, centred on the formboard panel.

How the Formboard Is Scaled

Every formboard is drawn at the same fixed scale, so the harness on a printed board always matches the real one. What you see falls into three groups:

Drawn at their real size - bundle lengths and bend radii, connector drawings, and bundle thickness when bundles are drawn at their estimated thickness.
Drawn at a fixed size - parts with no real size of their own: terminals, branch points, connector symbols, and bundles without an estimated thickness. They are drawn the same size as on the normal layout, which roughly matches the connector drawings: a terminal is about 1 cm across and a bundle a few millimetres thick.
Drawn at the annotation scale - everything that isn’t the harness itself: component labels and IDs, part bars, bundle lengths and coverings, notes, images, part images, pinouts, wiring tables, splices, diodes and resistors with their location arrows, mates, and the lines joining images and tables to their components.

The PDF exports are drawn the same way as the canvas.

Formboard Settings

Panel size

The physical size of a single panel. Panels are the sections your formboard is divided into.

Preset - Choose a standard panel size (A4, A3, A2, A1) or Custom to enter your own dimensions.
Orientation - Set a preset panel to Landscape or Portrait. (Hidden when the preset is Custom.)
Width / Height - The exact panel dimensions. Editable only when the preset is set to Custom; otherwise they follow the chosen preset and orientation.

Panel grid

Arranges multiple panels side by side in a grid to make up the full formboard. The overall board size is the panel size multiplied by the grid.

Rows - Number of panels down (1–64).
Columns - Number of panels across (1–64).

Default bend radius

The default corner radius applied where a bundle bends. You can override this for individual bundles — see Changing the Radius of a Bundle.

Annotation scale

A slider from 25% to 200% (100% by default) that sets how large everything except the harness is drawn: labels, part bars, notes, tables, pinouts, images, splices, diodes, resistors and mates (see How the Formboard Is Scaled). Turn it up to keep labels readable on a large board, or down to keep them out of the way on a small one. It never changes the size of the harness.

Setting a Bundle to 1:1 Scale

Bundles that are not to scale, or that have no set length, are drawn as yellow lines with black dashes so you can spot them at a glance.

There are a few ways to make a bundle’s drawn length match its set length so it renders to scale — adjust one at a time, or set the whole harness at once.

Use the match button

Whenever a bundle isn’t to scale, a yellow button appears on its length label. Click it and the bundle’s path is automatically adjusted so it is drawn at exactly its set length.

Drag a component into place

As you drag a component, a blue line previews where the connected component needs to be placed for the bundle to be to scale. The component snaps to that location. When the bundle is to scale, the line turns green.

When you edit a bundle’s length, the layout is automatically adjusted so the bundle is drawn to scale at the new value.

Set the whole harness to scale at once

A Set all bundle lengths to scale button in the controls at the bottom-right of the layout view does the whole harness in a single step: it moves components so that every bundle is drawn at its set length, exactly as if you had clicked the match button on each one.

Changing the Radius of a Bundle

right-click a bundle and set a value in the Radius field to change how tightly that bundle bends. Leave it empty to fall back to the Default bend radius from the formboard settings.

Adding Branch Points

In formboard mode, Add branch point places the new Branch Point exactly on the bundle line where you clicked, rather than on the grid, so splitting a straight bundle never introduces a kink. Layout points added to a bundle are placed on the line in the same way.

Bending Branches

Drag a single branch point and the entire branch connected to it moves with it — every component keeps its position and angle relative to that branch point, so the whole section swings as one rigid unit. Use this to bend and reposition entire runs of the harness at once.

To move connected components without rotating them, select them all with a click-and-drag box and move them together — dragging a multi-node selection translates only, with no rotation.

Bundle Thickness on the Formboard

When bundles are drawn at their estimated thickness, formboard mode draws them at their real size, so a bundle’s width on the printed board matches its estimated diameter, however thick it is. Only the very thinnest bundles are widened slightly so they stay visible. Connector drawings are also drawn at their real size. With bundle thickness turned off, every bundle is drawn a few millimetres thick.

Mates on the Formboard

Mates are drawn as curves that leave each connector square to its mating face, the same as on the normal layout, with the chevrons turned to match.

Wires on the Formboard

Selecting a component highlights the wires connected to it, and the formboard draws them beside their bundles in their colours, the same as the normal layout, ordered so they cross as little as possible where they branch. Each bundle’s wires keep to one side of it and follow its bends at the bundle’s own radius, and turn sharply where they pass from one bundle to the next at a branch point.

With Highlight nets turned off, selecting a single wire draws just that wire along the centre of its bundles instead, following their paths exactly, so you can trace its route on the board. Selecting a cavity with one wire on it, for example by clicking a pin on a pinout, does the same. With Highlight nets on, the highlighted wires are always drawn beside their bundles, even when you select a single wire.

Exporting your Formboard

From Main Menu → Export, a formboard harness gains an extra Formboard Panels option.

It exports a PDF with one page per panel in the grid, each page sized to your panel size and drawn to scale. Print the pages, lay them out in the same grid arrangement, and build the harness directly on top — for example, an A3 panel with a 2 × 4 grid prints as 8 to-scale A3 pages.

The number of pages equals the Rows × Columns set under Panel grid. The standard Export → Layout PDF still renders the whole formboard onto a single 1:1 page.

A formboard harness can also export its full geometry as JSON for digital formboard systems. See Formboard Data.