A bendable U-shaped paper edge protector is a U channel with a V notch cut through both legs at the point where it has to turn. The notch removes the material that would otherwise buckle, so the profile folds flat at a right angle and wraps the corner of a panel instead of stopping at it. Legs run 35-70 mm, walls 2.5-5 mm.
Why a plain U cannot turn a corner
A continuous U channel folds in one direction only. Push it around a corner and the inner leg compresses into a crease while the outer leg pulls apart, so the profile either kinks or opens.
Cutting a V out of both legs at the corner line gives the fold somewhere to go. The two halves close against each other and the profile stays square, holding both faces of the corner rather than one.
That is the whole product. It is not a flexible material and it does not hinge; it is a standard U profile with one machined feature that lets it do a second job.
Specification at a glance
The three numbers that matter are inner width, leg and the notch position. The notch is placed to the panel corner, so it is cut to the pack drawing rather than to a stock size.
| Panel | Inner width | Leg | Wall |
|---|
| 3-6 mm sheet | 6 mm | 35 mm | 2.5 mm |
| 10-18 mm board | 18 mm | 40-50 mm | 3-4 mm |
| 20-30 mm | 30 mm | 50-60 mm | 4 mm |
| 40-50 mm | 50 mm | 60-70 mm | 4-5 mm |
| Wide section | Up to 150 mm | 70 mm | 5 mm |
Where a bendable length beats a separate corner piece
A separate corner cap needs a joint, and a joint on a stacked panel is a place where the protection stops. A bendable length runs along the edge, turns at the corner and continues, so one part covers two edges.
That is cheaper on the line and stronger in the stack: fewer parts, fewer gaps, and nothing to fall between the panels when the pack is lifted.
The limit is the corner radius. A sharp corner folds cleanly; a rounded corner needs the notch opened or a short gap at the turn.
Fitting and the fold that keeps its angle
Fold the piece by hand on the bench before the panel goes in. Folding it on the panel puts the load into the panel edge, which is exactly what the protector is there to prevent.
Once folded, the two halves stay closed against each other and the angle holds. No adhesive is needed, and the piece can be unfolded and reused if the pack is opened and closed again.
Questions buyers ask before ordering
Is it a flexible material?
No. It is a standard kraft U profile with a V notch cut at the fold line so it can turn a corner.
Will the corner stay at 90 degrees?
Yes, once folded the two halves close against each other and the angle holds without adhesive.
How many corners can one length cover?
As many as you cut notches for. Most packs use one notch per corner and one continuous piece per edge.
What about a rounded corner?
The notch has to be opened wider, or a short gap left at the turn. Send the radius and we will cut to it.
Can it be unfolded and reused?
Yes. The fold is mechanical, so the piece can be opened and closed again if the pack is reworked.
Send the panel thickness, the corner angle and the pack drawing to mona@hengnicepacking.com and we will quote the protector that fits.
