Scale

How a sheet is told what it measures, and which scale wins when more than one applies.

Every measurement on a page comes from that page's scale. Nothing measures correctly until the scale is right, and nothing warns you that it is wrong, because a wrong scale produces perfectly plausible numbers.

Scale can be set three ways, and they are the same editor reached from different places:

• Typed, by picking a preset or entering the equation yourself. See Setting a scale.
• Measured, by calibrating against a distance you already know. See Calibrating.
• Per layer, where one layer on a page is drawn at a different scale from the rest of it. See Layer scales.

Which scale applies

When something is measured, the app takes the first scale it finds, in this order:

The layer's own scale

If the layer being measured on has a scale of its own, that is what is used.

The page's scale

Otherwise the page's scale applies. This is the normal case.

The default

If neither is set, a default stands in, and the number it produces means nothing in particular.

A layer scale is therefore an override, not an addition. Setting one does not combine with the page's scale; it replaces it for everything measured on that layer.