Dimensioning a Drawing

Place linear, aligned, radius, diameter, angular, arc length and ordinate dimensions, chain them with Baseline and Continue, add leaders, and control how they all look.

A dimension is a measurement written on the drawing — the arrow-ended line with a number on it that tells a builder how long a wall is.

In Pingendum 2D a dimension measures and reports. It reads the geometry, states the answer, and keeps restating it if the geometry moves.

What it does not do is drive anything. Typing a new number into a dimension does not resize what it measures — there is no constraint solver for it to talk to. To change a size, change the geometry: move a grip, use Lengthen, or Stretch. The dimension will follow along.


Prerequisites

Set the drawing's scale first

Dimensions are sized for paper and then multiplied by the drawing scale, so that the text and arrows come out a sensible size however big the thing you drew is.

They do follow a later change of scale — but it is much less confusing to set the scale before you start.


The basic move — DIM

Annotate ▸ Dimension (DIM):

  1. Pick the two points you want the distance between. (Or press Enter first, then click a line, arc or polyline segment to measure it directly.)
  2. Pick where the dimension line should sit.
  3. Carry straight on with the next one. Enter or Esc finishes.

Linear is the default, and it reads your cursor: you get a level dimension when the cursor is above or below the two points, and an upright one when it is beside them. A number typed at the last step sets how far the dimension line sits from the points, on the cursor's side.

OptionKeyWhat it does
ObjectOMeasure a line, arc or segment you pick, instead of two points
RotatedRType the angle the dimension line should run at
StyleSChoose the dimension style for the ones to come
TextTWhat new dimensions say, with <> standing for the measurement — <> TYP
The context bar while the Dimension command runs, showing its prompt and the Object, Rotated, Style and Text options
💡 Workflow Guide: Two dimensions in one run, without restarting the command. First the level one: pick the two bottom corners with Endpoint snap and place the line below them — 60.00. Then the right-hand edge, taken with R for Rotated and an angle of 90, which states the dimension line's direction outright instead of leaving it to be read from where the cursor sits. Sped up.

The seven kinds

Reach them from the Dimension button's submenu, by holding its palette button, or by name in Find a command (Dimension: Angular).

KindWhat it measuresWhat it asks for
LinearA horizontal or vertical distanceTwo points, then the line
AlignedThe distance along two points, at their own angleTwo points, then the line
RadiusA circle's or arc's radiusPick it, then where the line goes. Jogged (J) for a jogged radius
DiameterA circle's or arc's diameterThe same
AngularThe angle between thingsTwo lines, or an arc, or Enter and three points; then where the arc goes
Arc LengthThe distance along a curvePick the arc, then where the dimension arc goes
OrdinateA coordinate measured from the originA feature point, then the end of the leader — X if you go up or down, Y if you go across

Linear or Aligned? This is the pair people mix up. On a sloping wall, Linear gives you the horizontal or vertical part of the distance; Aligned gives you the true length along the slope. For anything sloping, you almost always want Aligned.

Ordinate dimensions are the ones used on machined parts and setting-out drawings, where every feature is given as an offset from one datum rather than as a chain of measurements. Set the datum with User Origin (UO) first.


Chains and stacks

Once you have dimensioned one span, two commands carry on from it — and the difference matters on site.

  • Continue Dimension (DC) adds dimensions end to end, each starting where the last one stopped. This is the running chain along a wall: 3000, then 2000, then 1500.
  • Baseline Dimension (DB) adds dimensions all from the first one's first point, each stepped further out. This is the stacked set measured from a single datum: 3000, then 5000, then 6500.

Both carry on from the last linear, aligned, angular or ordinate dimension you placed.

OptionKeyWhat it does
SelectSPick a different dimension to carry on from
UndoUTakes back the last one

Enter or Esc ends the run, and the whole run is one undo step.

The same two spans dimensioned both ways. Below, a Continue chain reads 3000.00 then 2000.00 end to end. Above, a Baseline stack reads 3000.00 and then 5000.00, both measured from the same left-hand datum and stepped outwards.

Adding words to a dimension

Select the dimension and type into the Properties panel's Text field, using <> to stand in for the measurement:

<> TYP
<> (to face of brick)

The measurement stays live — it is still read from the geometry — with your words around it.

Setting the text while the Dimension tool is running (option T) applies it to the dimensions you are about to place.


Editing a dimension afterwards

A dimension's grips are each measured point, the dimension line, and the text.

  • Drag a measured point grip to re-attach it to something else.
  • Drag the dimension line grip to move the whole dimension in or out.
  • Drag the text grip to move just the number — useful for getting it clear of a crowded area.

The value updates itself whenever the geometry it measures changes.


Leaders — LD

What a leader is. An arrow pointing at something, with a note on the end of it: "150 mm blockwork", "existing drain to be removed".

  1. Pick the arrow's point, then each bend in the line.
  2. Press Enter, or click the last point again.
  3. Type the text, and finish with Ctrl+Enter (or Esc).
OptionKeyWhat it does
No textNEnds with just the lines and arrow
StyleSPicks the dimension style, which decides the arrow
UndoUTakes back the last point

Leaders take their arrowhead from the dimension style, so they match the dimensions around them without being set up separately.


How they all look

Every dimension's appearance — arrows, text size, the gaps and overshoots of its extension lines, how many decimal places, tolerances, centre marks — comes from its dimension style. ISO and ANSI are built in.

Change the style and every dimension using it changes with it. That is the whole point of styles: you fix the look once, not dimension by dimension. See Styles and Annotation Scales.

For dimensions that must read correctly at several scales on the same sheet, make them annotative — see Annotative objects.


Dimensions, or the measuring tools?

You wantUse
A permanent annotation on the drawingA dimension
To read a value now, without adding anythingInquiry ▸ Distance / Area / List — see Measuring Geometry

Next Steps

Next: Hatching an Area