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Box damage · corner compression

LEGO box corner compression grading.

AI corner-damage grading for sealed LEGO boxes.

What corner damage is

How the AI sees it.

Corner damage on a sealed LEGO box is any deformation of the four corners on the primary face — typically caused by shelf weight, stacked storage, or shipping impact. BrickGauge measures it as compression depth in millimeters plus whitening at the corner fold.

Why it matters

The grader perspective.

Corners are the second-biggest grade driver after seal integrity. AFA's scale literally tracks corner depth in mm. A perfect box with one compressed corner still grades NM at best — the worst-corner rule applies because graders score the most-affected corner, not the average.

↦ Scored on the BrickGauge corners axis.

Severity tiers

Corner compression by tier.

Each tier maps to a defect signal and the grade ceiling it forces. Pre-grade your box with BrickGauge to see which tier yours lands in.

TierSignalGrade cap
MINTSub-1mm, no whiteningAFA 90+
NM1–2mm, light whitening at foldAFA 85
EX2–4mm, visible whiteningAFA 80
VG≥4mm, deep crease at foldAFA 75 or below
Prevention

Don’t create the damage.

  • 01Store boxes vertically — corner pressure goes to the spine, not the face.
  • 02Never stack heavy boxes. Even a 2kg load over 6 months will visibly compress the top corners.
  • 03Ship boxes inside a larger outer carton with 2-3 inches of padding around all corners.
  • 04If you must shelve flat, rotate the orientation every 6 months so no single corner bears constant load.
Get the verdict for your box

See your corner damage scored.

Upload six photos and BrickGauge measures the corner compression on your specific box, scores it on the corners axis, and rolls it into an overall verdict. Two free inspections on signup — credits never expire.

Corner compression FAQ

Frequent questions about corner damage.

How does corner damage affect LEGO grading?

Caps the grade. Sub-1mm: minimal impact (MINT possible). 1–2mm: caps you at NM 8.5 / AFA 85. 2–4mm: caps at EX 8.0. ≥4mm: drops to VG or below regardless of how good the seal and surface are. The worst-corner rule applies — graders score the worst of the four, not the average.

Can I fix a compressed corner on a sealed LEGO box?

No, and don't try. Steaming, ironing, or pressing a corner risks separating the seal stickers or warping the box geometry — both of which are worse than the original corner damage. AFA / CGC will detect the attempt and either reject the submission or annotate it on the slab.

Does corner damage on a LEGO box reduce its value?

Yes — typically 20–35% on sets where corner condition is the limiting factor. The dollar impact is proportional to set value: 35% of $3,000 Cafe Corner is $1,050 lost; 35% of $80 Creator set is barely worth the slab fee to find out.

LEGO Box Corner compression Grading — Value Impact & AI Detection | BrickGauge