[Shotimes] windshield crack

[Kevin & Cheryl Airth]

Mark:
 This brings up an interesting question. For a solid you are correct that a
round hole at the end of a crack will cut the stress riser factor down to
almost nothing. But glass is a super cooled liquid and is not really a
solid. Maybe the same idea works on a super cooled liquid or maybe tempered
safety glass is more solid like than regular glass?
.
.



> Another reason for drilling at the very farthest end of the crack is to
put
> a small round hole there.  This stops the crack from migrating any
further,
> similar to "preventing a stress riser".  That's why you have to be careful
to
> get it right at the very end of the crack -- if there's any bit of the
crack
> extending on the far side of it, probably it won't work.
>
> Cheers
> Mark LaBarre

> Try to  fix it soon after the damage occurs. You will get a longer lasting
> repair  if the area has not had much time to get dirt and moisture deep in
> the  crack or defect. That's what the drill bit is about. Open up the
damage
> a  little bit and blow it clean before applying the magic  goop.