heat repairs

[starman]

how many of you heat the repairs? I heat all of mind, but most of the time from the inside of the car,but I have try it on the outside of the car and have found that on stars the legs go away better. has anyone of you try this. Crayton 8)

[Coitster]

Hey Crayton,
I also use heat a lot. I don't heat all the time however most of the time I do. Make sure when you are heating up a chip is to make sure you let the windshield cool down under pressure. There are lots of people that don't heat the window correctly, or they see the chip dissapear (when what happened is they got the windshield too hot and the crack just closed because of intense heat and after they finish and the glass has cooled down the chip looks like it hasn't been fixed). I don't heat the glass up a lot, I just get it warm, and I make sure to let the glass cool under pressure, in case the resin is pushed back out of the crack I can heat it up again.

If there are cracks like a starburst or something, once I get it where I want it, I may of had to heat it up and let it cool down a few times I then cure the cracks under pressure. Then I remove the injector and cure the center of the chip. Also when you cure under pressure resin shrinkage is less of a problem. Chip will look a lot better. The key is knowing how to heat the chip correctly.

WARNING: if you over use heat, and get the window too hot you will crack it out, or resin won't flow into it, but it looks like it's been fixed until it cools down. I hope that helps.
David
Coitster

[starman]

Thanks for the vice I will remmber that. I was told in clss two years ago to heat 5sec on vacum and 5sec on inject two to three cycles. but then I was told to heat sowly on vacum untill the legs go away. but one day I could not get in the car and try it on the outside of car and it work great. Crayton 8)

[Repair1]

Starman,

Heat???? :twisted: well now that the snow is here I guess this would be a good time to talk about heating your repairs. Me personally use heat very rarely if it’s 65 degrees out side your window will be plenty warm you shouldn’t be using heat. You have to be dam careful if you cure it while it’s warm and the glass is expanded you will think your repair is complete then to find out everything opened right back up :shock: I’ve seen this soo many times over the years if you just remember heat is one of your last resorts you will find you really didn’t need it all that often. :idea:

I do use it more in the wintertime that’s for sure burr.. I think the key is not to hot. Warm it up on the inside slowly touch it with the back of your hand if it’s too hot to hold your hand there you’ve gone way to fare let it cool and heat less. Don't heat it untill the lines go away thats getting it to hot! Really all you need is about 70 to 80 degrees and like said before ALWAYS COOL UNDER PRESSURE.
Happy Repairing
Brian

[desertstars]

As we all know, when we heat, we expand the air allowing resin-flow to replace the air. Sometimes that pressure also knocks loose any minute gravel particle that may be lodged in a star crack leg.

To start, make sure your equipment isn't screwed down too tightly to the w/s.

After bridge application, give it time. I usually fill out all the information on my invoice before even checking the progress.

I then pull a vacuum and re-pressure.

If the result at that point is unsatisfactory, that's when I begin to heat.

I use a match, (you'll burn your fingers before you'll crack the w/s) with a circular motion to heat uniformly from the inside of the vehicle. Use a probe or finger pressure to help the flow if necessary.You can then either use a fifty/fifty spray mix of alcohol/water to cool the w/s down or let nature takes it's course.

By all means, let the w/s cool completely in order to check out the end result. I repeat if necessary but no more than two cycles.

As David suggests, I also cure under pressure.

Ordinarily, if there is "black in the crack", one doesn't need to heat. On thin cracks, I have already explained to the customer about "looking 85% better" and the "index of refraction". (I use a dime in the water to illustrate the point--you reach for it and it "ain't" there.) I inform the customer that because of that phenomena they "may" see a "sparkle" at certain angles when the repair is completed.

Almost without exception, they are pleased and happy with the end result.

Good luck.

(Anyone not familiar with that "index" might want to do a Google search--you'll find plenty of info on the subject.)

[Blind Squirrel]

If it's a penny for your thoughts and I put in my 2 cents worth, who gets the other penny?
Here goes nothing:
The only time I use heat is only from the outside and with a butane torch.
AND IT IS ONLY TO WARM THE GLASS TO MAKE IT "POP" EASIER when it is cool or cold weather.
I was taught a "drilling and popping" technique which I always do on Star breaks, seldom on bullseyes.
I NEVER USE HEAT TO AID IN RESIN FLOW. If the legs of a star break won't fill then they are simply not open.
Description of procedure for Star breaks with crack legs:
Drill into impact point "approx" halfway through outer lite. (takes practice)
At this depth, work your bit in a circular motion to slightly enlarge the impact point.
With a butane torch and only on the outside, WARM the glass. ITS NOT NECESSARY TO GET IT HOTTER THAN YOU CAN TOUCH IT.
Put your probe tip in the impact point and with moderate pressure on it, TAP around it and watch the 'CONNECTIONS" you are creating as you do.
Mount your injector and do routine vacuum and pressure cycles.
NOW, while under pressure, place your probe tip on the star legs and FLEX them. You will be able to see them open up and with moderate pressure, be able to watch the resin flow into and fill them to the end.
Sometimes, when a leg won't fill, I will release pressure and move my injector tip away, then, using the probe, pop again in the direction of the uncooperative leg. Then move the injector back over the break, redo the vacuum-pressure and flex some more and 99 times out of 100 that leg will then fill up.
Sometimes, due to positioning, it can be hard to "see" the legs. What I will do then is, release pressure on my injector and move the tip and bridge away from the break, leaving resin in the impact point and then FLEX around the break. This technique will make it possible to see legs you didn't know were there but SURPRISE! you can still make the resin flow and fill to the end even though you don't have it under pressure. I always finish the repair this way, then move the injector and bridge back over the break to cure under pressure. This is also why I use suction cup lube, because you can "slide" the bridge back and forth easily. Except for fleet situations where the vehicles are often locked, I always take the little bit of extra time to place a mirror on the inside of the car to help provide the best possible view, although it doesn't help when the break is in the blue band. This is the only thing I do on the inside of the car. I also cure "under pressure" as many do.
Anyway, I was trained in this technique by Bob Eimer, when I worked for Novus here in Denver a few years ago.
Please remember:
It takes quite a while to gain confidence and "get a feel" for how hard you can hit your tapper when you pop as well as how much pressure you can use on your probe when you flex.
Also understand that I don't think that my way is the only way but I am very confident in the quality of my work. That's how I would hope anyone who strives to uphold and promote the standards of this industry would come to regard their own efforts. Patience and caring are what really matters.
Thank you all for your support
Gary

[Repair1]

Gary that was very well put into words... I couldn't agree more :idea: :idea: :idea: :idea: VERY GOOD POST.... you deserve a round of applause
Brian

[desertstars]

Jeez, you've got it right about "patience" and "caring", Gary.

Your use of the butane torch and the caveat of NOT overheating is right on the money, also.

I still use a match and heat from the inside. If I heated from the outside, I would no doubt need a torch.

Since my system works and yours works also, it appears that in this case there's more than one way to skin a cat.

It IS difficult, however, to heat from the inside when the damage is low behind the dash. If I can locate my old pencil butane torch that I hid when I cracked a windshield about thirteen years ago, I'm going to give your method a shot.

Good input.