Community Forums

Gorlininc · 05-10-2014, 09:21 AM

I was driving and a rock chipped my windshield. I had it repaired months later when I got home. The repair guy said in the future put a piece of tape over it so it stays clean. It's makes for a cleaner and easier repair.
I thought I'd pass that on.

njs42 · 05-10-2014, 10:18 AM

Excellent as a matter of fact there are small stick on clear dots just for that purpose. A rock repair type gave me a few last repair I had done. (Wish I could remember where I put them)

distaff · 05-10-2014, 10:25 AM

It won't help to tape most cracks, as by then the damage is done. It really helps when it is still a stone chip, and in particular if you are going to experience any sub-zero weather. One of the main reasons a chip becomes a crack is that ice forms in the chipped area and distorts the glass.

njs42 · 05-10-2014, 10:29 AM

Quote:

Originally Posted by distaff

It won't help to tape most cracks, as by then the damage is done. It really helps when it is still a stone chip, and in particular if you are going to experience any sub-zero weather. One of the main reasons a chip becomes a crack is that ice forms in the chipped area and distorts the glass.

As I understand it the tape is not to keep it from cracking more (oh that it would be that easy) rather to keep fine road dirt from infiltrating the crack which makes it difficult to fill later.

pops2 · 05-10-2014, 11:20 AM

While I was cleaning my windshield on my 1999 Tradewind with 0000 steel wool and rainex I noticed a little crack made from a rock chip and the repair cost $50 to repair and was done in about 20 minutes. Now it is not noticable and the integrity of the windshield is safe.
The repair can be done at any glass shop on the spur of the minute, so don"t wait by using tape, get it fixed. It's cheaper then hitting a bump and having the windshield crack and have it replaced it.

distaff · 05-11-2014, 08:49 AM

njs42 - I suppose it might keep it clean, and in some cases by drilling both ends of the crack and injecting glue they can slow or stop it spreading, but in my experience it is usually a lost cause at that point.

We happen to live in a stone chip hotbed - average expectancy for a pristine screen is a year because they don't use sand on our roads here in Calgary, they use pea gravel and it takes out a lot of glass.

Regarding bumps causing chips to spread - not so much. It is usually water gets in and freezes, causing expansion in the chip that leads to a crack. The other common cause is differential expansion. Windshields are made in three layers, glass - plastic membrane - glass. When warmed by your heater on a cold day it will cause the inside glass layer to expand, the plastic layer provides some insulation so the outer glass layer starts to experience distortion and bingo - you have a crack. Glue helps prevent this by resisting the distortion at the weakest point.

Bumps don't usually cause an unequal distortion between the layers as the entire shield is exposed to the same distortion, and unless the chip is right at the edge, the pressure is fairly even. I drove my coach over the Rockies and back this spring with a pretty big chip in it (I had tape over it). Lots of potholes and "irregularities" in the road surface including the all time worst bump just west of Field BC. So bad it opened the hood on my Suburban I was towing. I didn't see the discreet little sign they had up warning because I had run up behind a semi so I didn't get a warning.

In any case, the chip is still a chip. But I'll fix it soon.