Some of the unsung work we, as windscreen fitters do, is in bodyshops (or accident repair centres). Working as the subcontractor for a crash repair garage can be bread and butter for some firms or the staple income for a lot of windscreen companies. Here is an example of a quick turnaround job: the tailgate transplant.
The new tailgate is painted as the old, crashed one is removed from the car and stored. On the day of the swap, the new painted tailgate will be hung on the car, and work to transfer all the parts begins. The bodyshop fitter will remove all the parts leaving the glass to the specialist:
There are various ways to remove the glass, some methods are better than others. This glass was removed with a square-profiled wire.
Work then begins or preparing the newly painted tailgate. A minimum period of 24 hours must pass after bake before a bonded application can be introduced to fresh paint. With this in mind, a few checks are still necessary to satisfy the installer that the substrate is suitable for bonding to. The new tailgate preparation begins:
There are many polyurethane adhesives on the market. For this job, Sika’s Sikatack Drive was used. Despite its excellent primer-less application, the manufacturer recommends use of a primer – or adhesion promoter – on freshly painted surfaces. But before that, the surface is ‘scratched’ over the bond line to provide a ‘key’ for the primer to adhere to:
Following Sika’s guidelines, the surface is ‘activated’ as preparation for the primer, but also to remove any particles of dust or contaminants. After observing the requisite flash off time, the (black) primer can now be applied:
Whilst the primer dries, the glass can be prepared. This is a delicate process of cutting back the old cured adhesive and cleaning the surface. Care is taken not to catch or damage ant hardware on the glass, especially the heater elements. Again, following manufacturer instructions, the glass is prepared before fresh (polyurethane) adhesive ( “PUR” )is applied. The glass is marked indicating the date, the installer’s identification as well as the corresponding batch numbers for the PUR for traceability.
Finally, the ‘transplanted’ heated rear windscreen:
Comments and questions welcome.