Sheet metal
Two bends that meet at a corner of a base face without a corner relief and whose bend zones overlap when unfolded into the flat pattern (material that would have to exist twice; Protocase, SendCutSend, DFMPro: relief width >= t, depth >= R + t). Closed corners whose unfolded bend zones are disjoint are shop-typical and not reported.
No standards reference is assigned to this check. The scope described above applies.
Sheet metal · CC0-1.0
Model example
A 100 × 60 × 25 mm tray whose four walls are bent from one blank and meet at the corners with no relief: where two perpendicular bends meet, their bend zones overlap in the flat pattern. Inspect the four corner bends.
Dimensions (approx.): 102 × 26 × 62 mm
PRU-109 should warn that the corner bends have no relief (and nothing else).
Finding expected
Sheet metal · CC0-1.0
Model example
The same tray with each wall shortened by 8 mm at both ends, leaving a corner gap.
Dimensions (approx.): 102 × 26 × 62 mm
PRU-109 must stay silent: the corner gap relieves the bend zones.
No finding expected