Last updated 10 August 2026
Yes. Perpendicularity is a relationship, so a feature control frame carrying it with an empty datum compartment has not said anything yet.
The same is true of parallelism and angularity, and of the location and runout controls. All of them state how a feature relates to something else, and without a datum reference frame there is nothing for the relationship to be measured against.
The rule runs the other way for form controls, which is the half most charts leave out. Straightness, flatness, circularity and cylindricity are checked against the feature itself, so a datum on one of them is not extra rigor, it is a contradiction.
| The frame | ⊥|0.005 |
|---|---|
| Control | Perpendicularity |
| Family | Orientation control |
| Datum reference | required |
| Diametral zone | allowed |
| Material condition modifier | allowed |
| Legal under ASME Y14.5-2018 | no |
Open this case in the calculator, and change the numbers.
Computed by ctrlPlanner. ASME Y14.5-2018.
This checks one frame. ctrlPlanner keys the whole print, keeps every frame intact through the control plan, and carries them onto the AS9102 forms.
Open the demo · a print is already loaded, no sign up.