Not every pack has a square corner. A tapered crate, a chamfered plinth or an angled frame needs a protector that folds to something other than 90 degrees, and the angle has to be cut rather than forced. A paper U channel can be notched to any angle between about 45 and 135 degrees, with 90 as the standard.
How the notch sets the angle
The V cut into the legs is what allows the fold, and the width of that V decides how far the profile closes. A narrow V closes to a sharp angle; a wide V stops at an open one.
That means the angle is a cutting specification, not a material property. The same board and the same inner width produce a 60 or a 120 degree piece depending on the notch.
Specification at a glance
The table pairs the common angles with what they are used for. Anything outside the range is usually a different product rather than a different notch.
| Angle | Typical use | Note |
|---|
| 45 degrees | Mitred frame corner | Near the sharp limit |
| 60 degrees | Chamfered crate | Common |
| 90 degrees | Square panel corner | Standard |
| 120 degrees | Open angle pack | Common |
| 135 degrees | Tapered edge | Near the open limit |
Angles that cause trouble
Very sharp angles, below about 45 degrees, close the two halves onto each other and the legs overlap. The paper has nowhere to go and the fold creases.
Very open angles, above about 135 degrees, barely need a notch at all; the profile can simply be bent by hand. A notched part at that angle is usually a mistake in the drawing.
Compound corners, where the profile turns in two planes, cannot be made from one notch. They take two pieces or a moulded corner.
Confirming the angle before the run
Send the angle plus a sketch of how the protector sits on the pack, because the same angle measured on the outside of the corner and on the inside differ by the board thickness.
For a first order, a short run checked against the pack is cheaper than a full batch that folds 5 degrees off. Angle tolerance is set by the notch, and a notch cannot be adjusted after cutting.
Questions buyers ask before ordering
What angles can you cut?
About 45 to 135 degrees, with 90 as the standard.
Is the angle set by the material?
No, by the width of the V notch cut into the legs.
Why does my 90 degree piece not close fully?
Measure on the inside of the corner. The outside measurement differs by the board thickness.
Can you do a compound corner?
Not from one notch. It takes two pieces or a moulded corner.
What tolerance is normal?
Set by the notch. Send a pack sample for a first order so the angle is checked before volume.
For a quotation, post the panel section, the angle and the destination port to mona@hengnicepacking.com.
