Glass temp question again

[jonnyques]

Hi Well you guys have tought me how to cool and now Im learning how to do a good warm of the glass. Ive seen some strange things and I just want to put it out there for comments. Im wondering if I have warmed the glass to much. Im doing it to what I feel is comfortable (exteriour) to the back of my hand. I then have done the repair, pit filled, finished etc. I then see black where ther was no black before? Ive started after some past posts to examine a fill before curring to make sure it is black free. These ones were. As I said after curing there it was. Im wondering if the glass is cooling in that cure time causing any expanded glass to open up, causing the black? Its the only thing I can think of? Once the glass is warmed by the defrost I shut the car off to not over heat the glass. I cleaned my contacts cause I think Im seeing things! Any thoughts? Thanks!! O and on a side note I drilled into the black and refilled, they came out great!

[Coitster]

Let me tell you what I do. For years I worked in very cold climates and scrapping ice off of windshields to get to a chip is not fun I will tell you.
First thing I do is turn the defrost on and during the whole job I will leave the defrost on. That takes care of the inside of the glass but remember you have the elements on the outside of the glass counter acting the defrost and sometimes the changes in temp can cause problems so this is what I did to counter act it. I went and bought myself a heat gun at the story. I would start off buy standing at the end of the hood and heating the windshield from the outside. Its very important to not stand to close with the heat gun because of the fact they are extreamly hot. So you want some distance. Once I had the windshield to about 50 degree's I would begin working on the chip, I really didn't get it to much hotter then that. Also when the glass is cold I am very cautious about how much pressure I put when I am flexing the glass. Anyway thats what I did when I lived in a cold climate, yea it added about 10 minutes to my repair but hey, I was one of the only ones doing repairs in that kind of weather so I go lots of business because of that. Hope some of that helps.
David
Coitster

[Ridge Runner]

Hey David, Did you have access to A/C electrical source or were you using an inverter? Thanks

[Coitster]

I always use an electrical source. I carry two 100 foot extension cords with me at all times.
David
Coitster

[glassdoctor]

99% of the time I use one of two heat sources, or both.

1. Vehicles defrost
2. Propane torch (think of it as a cordless heat gun )

Black lines appearing suggests the glass may be too hot, and cooling at the "wrong" time of the repair/curing. Or, perhaps the glass is cooling too much during the repair and what you think is "done" actually needs more cooking time.

It's not uncommon to have a repair look pretty clear when you remove the injector, but after a couple minutes you can see some areas not 100% filled. My guess is that's the real issue... 98% filled but not 100%.

Rather than turning off the car's heater once the glass is warm, just set it to floor or vent, or adjust the temp control. This will give you a more consistent glass temp and as much time as you need to play with the repair.

[StarQuest]

Isn't winter repairs challenging? I actually love it. I generally use three different torches. First is the Master Blaster (propane plumbers torch to totally defrost working area) Second is a mini butane torch to heat up one-two inches from damage and third is my butane heat pen which I use directly on damage area. My heat pen only blows hot air, so it's totally safe from burning laminate or shocking glass. I also use my heat pen during vaccum around the injector but never during a pressure cycle. Using these methods support a average repair time around 15 minutes at 5-10 degrees outside temps. In the past I'd start vehicle, wait 10-15 minutes for shield to defrost and then spend another 10-20 minutes to repair. That's 30-35 minutes per repair. Much to long for me.

Note:

Most techs in my area have already closed shop and are either hunting this week or sitting home packing on some pounds in front of the TV set. For all you newbies I have only one statement to make. "This is the best time of the year to grab new accounts." Even if the weather conditions aren't favorable for repair, simply just visit these locations weekly. Believe me, once they sense your commitment by working like a crazy man in 10 degree conditions, they'll be finding work for you and pulling vehicles in the shop. In the last three years of business, I've opened 70% of new fleet accounts between the months of November-February. Wonder why?

[Coitster]

StarQuest,
Great post man. I also work in the winter time. You are right, its easyer to get business as long as its not raining.
David
Coitster

[GlassStarz]

I find this time of year my kill rate goes way up people around here know that the 20 below days are coming and they better fix that chip now!

[Don Boccafola]

I also like to use those sun and rain bubles in th winter. I pop it onto the w/s,throw a towl around it and blow some heat binto it with my plumbers tourch. It's like working in a mini green house. I think I get them from Glass Medic for about $75.00

[jonnyques]

I have a heat pen, torch, and a heat gun. Im just woried about cracking one out by heating to fast. Since this post Ive been running the defrost and monitering the heat , turning down when it gets hot. Ive also tried to warm a large area around the break with the heat gun to bvring up the outside temp of the glass. At this stage of the game Id rather error on the side of caution. I have a hair dryer mounted to a piece of loc line and a pump up suction cup. Im thinking this could conme in handy to keep the area warm. Ive used it in PDR.
Thanks