Bond quality should be verified by measurement, not by eye. Regular testing prevents complaints, catches process drift early and gives an objective basis for comparing suppliers.
Core tests
Peel test: measures the force to separate a flexible material (film, fabric, edge band) from a rigid surface. The most common test in edge banding and lamination.
Lap shear test: pulls two overlapping parts apart in shear to measure structural strength. EN 205 for wood adhesives is based on this principle.
Heat resistance test: finds the temperature at which a loaded specimen fails. Critical for kitchen furniture and automotive.
Water and humidity test: strength after soaking or boiling (the D classes).
Ageing test: temperature and humidity cycles simulate long-term performance.
Practical checks on the line
- Hand peel test: band a few samples at shift start, peel them and record the failure mode.
- Coat weight check: weigh before and after application.
- Temperature log: check tank, hose and nozzle temperatures regularly.
- Visual check: glue line thickness, squeeze-out and charred particles.
Record the failure mode
The failure mode matters as much as the force. Substrate failure is the goal; adhesive failure points to surface preparation, cohesive failure to adhesive choice.
A simple control plan
| Check | Frequency | Owner |
|---|---|---|
| Adhesive temperature | Every shift | Operator |
| Coat weight | Daily | Quality |
| Peel test | Every shift | Operator |
| Heat resistance | Weekly / batch change | Quality |
Let's build your quality control plan and test methods together.
