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Repairing cold windshields

Posted: December 12th, 2008, 5:24 pm
by WinkyTheWindshield
What do you guys do when you're on a mobile, the customer is not there, and the car has been sitting in the cold for a while. I haven't had a cold damaged windshield crack on me while I was repairing it, but I do know the cold temperature does make it more susceptable to cracking. What techniques do you guys use to prevent a cold windshield from cracking. Does the moister evaporator work? and if so, how do you use it?

Re: Repairing cold windshields

Posted: December 12th, 2008, 7:13 pm
by Kgobin
It is best repairs is to do repairs under cover whenever possible, but of course this isn't always possible, but if a shop is available use it. In my opinion if you do repairs in a controlled environment will lead to more consistent results. I recommend warming the glass to between 70 and 90 degrees for best results. Make sure you warm the glass slowly. When glass is cold, it doesn't respond well to sudden temperature changes, so be careful! One thing that many technicians overlook is their equipment and resin. Make sure your resin and injector are not too cold. Many windshields have cracked out from the application of cold resin on a warm windshield. Carefully flex the break with your probe and look for moisture movement. Often a repair that has a lot of moisture or liquid contamination will appear partly filled. Your best weapon in the fight against moisture is common sense. If it has been raining recently or if there is dew present on the windshield, odds are there is moisture present. If you aren't sure, then you need to treat the break as if it has moisture in it. The moisture evaporator is the most effective tool I have used to get rid of moisture because it is effective and simple to use.

Re: Repairing cold windshields

Posted: December 12th, 2008, 8:15 pm
by GlassStarz
I worked several winters in sub zero weather When Im working cold i do a couple things first I have a couple of those heat packs that warm up when you expose them to air I keep em in the gloves I pull it out wrap it in a paper towel lay it on the glass over the break with a terry towel on top it will slowly warm the glass I keep my bottle of resin in my front pocket and also have another heat pack in the tool box so the injector and suction cups are not frozen. I tried hrowing a electric blanket on the windshield for awhile it worked great but power was hard to get in some places also some will use a heat gun or blow dryer I found often this brings the temp up too quickly and presents the crack out possibility the easiest solution is the one I recently started doing I moved to a warm climate :P :lol:

Re: Repairing cold windshields

Posted: December 12th, 2008, 9:21 pm
by t4k
GlassStarz wrote: the easiest solution is the one I recently started doing I moved to a warm climate :P :lol:
GlassStarz you are a real piece of work.....I love your sense of humor.

Re: Repairing cold windshields

Posted: December 13th, 2008, 1:40 am
by Frank EU
We mostly do fleet work and we know the details (about the customers, the locations etc.) pretty good. That work is mostly done at saturdays and sundays and not many people are available to us to move the vehicle, indoors or somewhere in the sun. We also like to make the most out of our days, so we like to start ''early''. This means that we cannot and will not wait for the sun to come out and be nice to us. At cold winter days we start at fleets where we expect the sun would have warmed up the windshields a bit. We rarely heat up the glass ourselves, just don't like that principle, instead we keep our stainless steel injectors warm. If it is a private customer we make the appointment including a request to have the windshield be heated up upon our arrival.

Re: Repairing cold windshields

Posted: December 13th, 2008, 11:35 am
by Brent Deines
I like hair dryers for heating from the outside when necessary, but you still need the moisture evaporator to dry out the break after the windshield is warm. A suction cup and a piece of Velcro are handy to hang your hair dryer on the glass so you can keep the glass warm during the repair process. The hair dryer will also keep the injector and resin warm. I used a hair dryer a lot in Oregon, but in Montana found it to be a must.

Re: Repairing cold windshields

Posted: December 13th, 2008, 10:20 pm
by WinkyTheWindshield
Thanks for the insight guys, I appreciate the feedback for all of your different techniques. If anybody else has a technique that they use, please don't hesitate to post it.

Re: Repairing cold windshields

Posted: December 13th, 2008, 10:48 pm
by Roo
Hey Brent, did you use a 12v hair dryer if so did you run it with the battery pack? I was thinking about picking a 12v hair dryer for the cold Colorado mornings buy wasn't sure how the battery pack would support that kind of power.

Re: Repairing cold windshields

Posted: December 13th, 2008, 11:11 pm
by SGT
Roo,

12V travel hair dryers will run off the DK mobile battery pack just fine. I have one but it really at best gets luke warm and I do not use it. Should you have an issue with the battery pack just switch out the 7.5amp fuse with 10amp fuse. If I have access to the car I like to pre warm the vehicle and use the moisture evaporator to warm the exterior repair area and then use it to remove moisture. Make sure you monitor temp. as you are warming to avoid thermal shock. Once the repair is in progress I use my simple but effective BIC lighter to assist maintaining optimal temp. in conjuction with my temp sensor. from the inside.

Re: Repairing cold windshields

Posted: December 14th, 2008, 10:36 pm
by Brent Deines
Roo wrote:Hey Brent, did you use a 12v hair dryer if so did you run it with the battery pack? I was thinking about picking a 12v hair dryer for the cold Colorado mornings buy wasn't sure how the battery pack would support that kind of power.
I did use 12V hair dryers, but I have never found one that was of very high quality, and as SGT said they often don't get all that hot. They will run off the battery pack, but if used the way I like to use them in cold weather it will drain the battery pretty quickly. I prefer a good AC unit with variable heat and fan speeds so I can control the temperature of the glass throughout the repair process even in the coldest weather.