concept

Variables, units, and expressions

Reuse dimensions and calculate Distance, Angle, and Number values in numeric fields.

Variable types#

Open Variables to create reusable project values. Distance stores a length, Angle stores an angle, and Number stores a unitless scalar. Give each variable a clear name and use that name in compatible numeric inputs.

Supported units#

Distance expressions accept millimeters (`mm`), centimeters (`cm`), meters (`m`), inches (`in`), and feet (`ft`). Angle expressions accept degrees (`deg`) and radians (`rad`). A value without an explicit unit is interpreted for the field and current project unit.

The numeric keypad shows a live result in the current project unit. For example, entering `0.015` in an inch project previews `0.015 in`; entering `0.381 mm` previews the same length as `0.015 in`.

Changing Project Setup > Units preserves the physical size of existing dimensions and features. Existing saved expressions retain the unit used when they were entered; an expression may show this explicitly as `mm{1+1}` after you change units. New expressions without a unit use the project's new unit. For example, `mm{1+1}` remains 2 mm even in an inch project, while a new `1+1` in that project means 2 in.

Expression examples#

Expressions support variable names, parentheses, `+`, `-`, `*`, `/`, powers with `^`, and the constants `pi` and `e`.

width / 2
(height + 10 mm) * 2
360 deg / toothCount
2 * pi * radius

Only compatible dimensions can be added or subtracted. Multiplication and division can derive or cancel dimensions, but the final result must match the field: a distance for length inputs, an angle for angle inputs, or a unitless value for Number inputs. Division by zero, unknown names, incompatible dimensions, and non-finite results are rejected.

Editing dependencies#

When a feature uses a variable, changing the variable rebuilds dependent results. MakerSolid keeps the source expression as well as its last valid value. If an edit becomes invalid, correct the expression or cancel before continuing.