Outsole gluing and edge finish
The bond line between the outsole and the midsole, and whether adhesive has spread past the edge where it will collect dirt.
The reading sequence
3 steps, starting at structural defects and running to press the edge and watch for movement. Evidence on this point is read at E1, and 1 of the 3 steps carries a condition that ends the assessment outright.
Shoot the bond line all the way round one shoe
Get a continuous view of the bond line rather than two flattering angles.
Evidence: E1 — four photos at heel, medial, lateral and toe, close enough to read the line
- All four photos show an unbroken bond line with no gap wider than a hair.
- The same photos are repeated for the second shoe.
- Three of the four angles are supplied, leaving the toe or the heel unverified.
- Only wide shots are supplied, where the bond line cannot be read at all.
- One shoe is photographed and the other is left out.
Look for adhesive outside the bond line
Decide whether any adhesive has squeezed out past the edge, which is where it will trap grit and turn dark.
Evidence: E1 — the same four close photos, examined at the edge rather than the centre
- No adhesive is visible outside the bond line on either shoe.
- Where the sole meets the upper, the material is clean on both sides of the join.
- A single spot of squeeze-out under 1 mm near the heel that can be picked off without lifting the bond.
- Adhesive runs along a section of the edge, which is a spreading error rather than a slip.
- The squeeze-out has been wiped, leaving a dull scuffed band on the upper.
Press the edge and watch for movement
Test whether the bond actually holds, using pressure rather than appearance.
Evidence: E1 — a short video of the seller pressing the sole edge at four points
- The bond line holds at all four points with no visible opening.
- The seller presses with a thumb rather than a tool.
- The video covers two points only, leaving the heel and the toe untested.
- A gap opens at any point under thumb pressure.
- The seller declines to send the press test, or presses so lightly that nothing is being tested.
Why the thresholds sit where they do
Bond line failures are the clearest example of a defect that photographs can hide and pressure can reveal. Wide shots are the standard seller photo because they flatter the shape, and the bond line is precisely the detail they leave out. Adhesive squeeze-out matters less for looks than for what it collects: the edge is where footwear meets the ground, and a smear there darkens within days and cannot be cleaned back to the surrounding finish. The press test is placed last because it is the only step that can be run without judgement, and because a seller who will not run it has answered the question a different way.
Common misreads
2 pairs recorded for this point. Each runs in both directions: 1 finding that looks worse than it is, and 1 that looks better.
- looks like Return actually Query
A dull band along the sole edge that could be either wiped adhesive or a moulding seam. Ask for a close photo at an angle, where a seam casts a shadow and a smear does not.
- looks like Pass actually Query
Clean photos with no press test. A bond that looks continuous can still open at the heel, which is the point that takes the most load.
Check this point against what you were sent
Insufficient evidence
Nothing decided on outsole gluing and edge yet: 0 of 3 steps have been read.
0 of 3 steps judged
| Step | Reading | Evidence | Stop met |
|---|---|---|---|
| 1. Shoot the bond line all the way round one shoeneeds E1 | — | ||
| 2. Look for adhesive outside the bond lineneeds E1 | — | ||
| 3. Press the edge and watch for movementneeds E1 | A gap opens under thumb pressure. The sole is not bonded, and it will separate with walking regardless of how the photos looked. |
Sources and checks
- Public community thread — Reports where sole separation appeared within the first monthn=39
- Editor analysis — Press test wording designed to produce a yes or no answerno sample
Last checked · next review due · status current.
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