Windshield Repair Forum

screenman wrote:Or warm the inside and the outside at the same time. I use and always have used the top vents, not one break out in 27 years.

I agree! We can talk about theory all day long but the proof is in the puddin.

Crackouts from defroster use only do happen. My brother-in-law, who is a very cautious individual, upon my advice to start engine, turn on defroster while engine is still cold to warm glass gradually, had a small combo break about 4 inches above passenger side wiper blade, crack beyond repair. It was 17 degrees outside with about 1/8 of an inch of ice coating the glass to begin with. Apparently even a gradual warmup like that is not always going to work.

Unfortunately it would take all day with just the cabin heater to warm up a windshield with 1/8" ice on it and it is always possible damaged glass will crack out regardless of how slowly it is warmed or cooled. I once brought a car into my 65 degree shop and because the customer was leaving the car all day and I had other jobs to do I allowed it to warm up for several hours with no additional heat what-so-ever and still had the glass crack.

However, I agree that heating the glass too rapidly increases the risk of cracking and I also agree that slowly warming from both sides of the glass at the same time is optimal when heat is necessary. If you break a lot of glass or if you are uncomfortable using the defrosters and don't find the need to do so, that's great! If on the other hand, you have been using the defrosters for nearly three decades with no resulting crackouts, or you live somewhere where there simply is no safer way to warm the glass in a realistic period of time, I wouldn't rule them out. Many of our customers in Alaska, Canada, Russia, Norway, etc., would have a very difficult time thawing a windshield without the defrosters. There are some pretty dang cold places here in the good ol USA as well, especially this year. As long as it is working for you and your customers that is all that matters.

Either way I'm getting cold just thinking about waiting for 1/8" of ice to melt off a windshield so I can repair it. Come on Springtime!

In the Bay Area and California we have a drought for past 2-3 years. I had to use my heat exchanger this weekend to cool down the WS! Maybe have another "side" bizniz like headlight restoration or side lite, dent repair. When you are mobile it is tough to add on without having a retail location. Diversify if possible. Best of luck. And don't stress spring is almost here!