Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
51 31... Notes on window bonding: Hardening
The adhesive hardens as it reacts with air humidity (with accelerator also due to mixed-in reaction paste) at room temperature.
Minimum hardening time (table) is obtained from 22 °C and 38 % relative air humidity.
At ambient temperatures above 23 °C and 50 % relative air humidity (hot countries), the adhesive open time is shortened to approx. 5 minutes (skin formation time).
The adhesive hardening process is interrupted completely at ambient temperatures below 5 °C. In this event, there will be no increase in the strength of the bonded connection.
Do not subject the vehicle to load on one side during the minimum hardening time (see table, without front passenger airbag), such as e.g.:
- one wheel on curb
- vehicle hoist
- etc.
Maneuvering inside garage/workshop:
- only permitted on level ground
- do not under any circumstances drive over approach ramps, e.g. into multistorey car parks
Remove adhesive tapes after hardening time.
If you fail to adhere to the minimum hardening times (see table, without front passenger airbag):
- Leaks and/or wind noises may occur at the window glass
1-day system: Adhesives and their minimum hardening times:
| Adhesive | Minimum hardening time "without front passenger airbag" (after which vehicle can be moved) | Minimum hardening time "with front passenger airbag" (countries where seatbelt use is not required by law) |
|---|---|---|
| Hot working with accelerator | 2 hours | 3 hours (1) |
| Cold processing | 9 hours | 20 hours (1) |
1-hour system: Adhesives and their minimum hardening times:
| Adhesive | Minimum hardening time "without front passenger airbag" (after which vehicle can be moved) | Minimum hardening time "with front passenger airbag" (countries where seatbelt use is not required by law) | ||
|---|---|---|---|---|
| Cold processing | 1 hour | 2 hours(1) | ||
Vehicles with front passenger airbag: The vehicle can be handed over to the customer after the hardening time (vehicle can be moved, adhesive-dependent) with the following warning: Once the windscreen glass has been bonded, all occupants must travel with their seatbelts attached for "... hours"! The time is taken from the "Minimum hardening time" table for countries where seatbelt use is not required by law. |
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- the front passenger together with the windscreen may fall out of the vehicle in the event of an accident after the front passenger airbag has been triggered
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.