Volume 10, Issue 5 - September/October 2008
Ask the Doctor
Q: HOW CAN YOU TELL IF YOU have a break properly filled in the frit band since it is difficult to see what you are doing?
A: The frit band is a ceramic application around the edge of the glass part. The band helps to hide the trim and pinch weld areas, but, more importantly, inhibits the degradation of the urethane by blocking a majority of ultraviolet (UV) rays. Because of its black color, it creates a challenge in the repair process, though.
The key to repairing a break in the frit area is relying on the play of light and shadow on the black background of the band. The configuration of the break usually reflects off this black background, so when the break is properly filled, only the pit area should cast a shadow on the frit. If any other part casts a shadow after it has been fixed, then that area is still open.
Repairing the area is not the hard part—it is knowing when it is totally filled that is the problem. Once the UV shield is applied, the light on the frit is changed and the tech can “lose the repair” because the shadowing has shifted or is completely gone.
A common trick to double-check
the repair is to flip up the UV shield
quickly to expose the area to light.
Unfortunately, this could lead to premature
curing; because of this, a
clear bubble dome or a clear UV
shield is prefer-able over a colored