How to Add Tolerance in AutoCAD. Adding Tolerance

When determining the dimensions of parts to be manufactured in mechanical technical drawing, depending on the area the part will be used in, it’s sometimes stated that the dimension can fall within a certain range. The manufacturer must keep the part’s dimensions within this range. We simply call this tolerance. For detailed information about tolerances, see: What Is TOLERANCE in Technical Drawing?

How to express tolerances when dimensioning in AutoCAD is a topic many users wonder about. We dedicated this article to adding tolerance when dimensioning in AutoCAD.

How Is Tolerance Added in AutoCAD?

You can add tolerance directly in AutoCAD using the DIMSTYLE (Dimension Style) dialog box. For the DIMSTYLE command, type D on the keyboard and press space (or ENTER). The Dimension Style Manager window will open.

In the window that opens, click the NEW button. This way we’ll create a NEW style, and use it for the dimensions we want to show with tolerance.

Then, in the window that opens, give your style a name and select LINEAR DIMENSIONS in the USE FOR field

In the window that opens, this time go to the TOLERANCES tab at the top, and then make the settings shown above. (The settings in the area marked in red)

Click NEW again, and this time change the field we set to LINEAR DIMENSIONS in the previous step to ANGULAR DIMENSIONS. (We’ll set up the angular tolerance display)

Go to the TOLERANCES tab again, and this time enter the upper and lower tolerance values as 0.04 instead of 0.05 from the previous step.

We’ve now set up the toleranced display style for linear and angular dimensions. Now we’ll use the same method to configure the RADIAL dimensioning style, used for dimensioning diameters and radii.

This time, instead of selecting LINEAR and ANGULAR DIMENSIONS as in the previous steps, we’ll reach the same window by selecting RADIUS DIMENSIONS. In the window that opens, this time we’ll enter 0.02 as the lower and upper limits. (Picture above)

Adding Tolerance to AutoCAD Drawings

In the previous steps we created a new dimensioning style, and from now on, the dimensions we create will show with tolerance — unless you select a different style from the DIMSTYLE or PROPERTIES menu.

If Angular Tolerance Doesn’t Show Up in the Dimension

We set up our style. When we go to dimension the drawing, we notice the angular tolerance isn’t showing. The upper and lower tolerances might be showing as 0. Don’t worry if this happens.

For the tolerances to show up, you may need to change the “PRECISION” of the angular dimension.

To fix this, go to the “Primary Units” tab of the angular dimension style, change the “Precision” value to 0.00, and click the OK button. (Picture above)

We now have a new style in the DIMSTYLE MANAGER window with LINEAR, ANGULAR, and RADIAL dimensioning options. (Animated image above)

From now on, unless you change styles from the DIMSTYLE menu, the dimensions you place in your drawings will look like the image above.

How Do I Go Back to the Old Style?

You open AutoCAD and notice all dimensions are being shown with tolerance. But you want tolerances not to show. To go back to your old classic style, open the DIMSTYLE window. Select your old style and click the SET CURRENT button.

To Express Some Dimensions Without Tolerance

Click the dimension whose toleranced/untoleranced display you want to change. Then select your dimension style from the PROPERTIES menu. The dimension style will change instantly.

Changing Tolerance Values

We set default numbers like 0.05 in the DIMSTYLE window, but you can change tolerance values within the drawing without messing with DIMSTYLE again.

To do this, click the dimension whose tolerance you want to change. Then scroll down in the PROPERTIES menu. You can change these values in the Tolerances section. (Picture above)