Oops! I cracked one out!!!!

[GlassStarz]

I think the problem is just as likely to happen with a star as the bat and sometimes the easy bull has a hidden underlying crack that suddenly appears so my advice is to be careful always as far as poping a bat I never pop anything just dont believe further breaking the glass is productive I try not to drill anymore than needed (maybe 1 in 10) once my technique got better I found breaking or drilling wasnt needed anymore.

As far as why they break and how to avoid itI think the science is generaly cool inside layer hot outside layer and then the added pressure and flexing results in unstable glass with potential of increasing the break. Getting both sides cool and covering the windshield to keep the sun off while applying pressure slower than normal is the answer to not losing any that said I will probably go out and break one tomorrow.

[screenman]

If you look to a previous post on batwings there was one a short while ago you will see that a lot of us drill and pop. The reason I do this this is to open up the break making it less tight and therefore easier to fill. In my exprience the batwing is the most likely small damage to run out of most of the breaks we repair. (now I am sure someone is going to disagree with me there.)

I am still not sure why people are relunctant to pop and drill when done properly it is a great tool and will leaves no cosmetic difference to the finished product I look foreward to the comments on this subject.

[mafsu]

I agree with screeenman. Some will argue that drilling and popping will make the finished repair more noticeable. Any cosmetic difference is so negligible, it would take a seasoned repairman to tell the difference. However the difference in the ease of the repair will be dramatic.

[magicogar]

Sallyu,

The impact point of the batwing was so small that I figured I may need to drill. So I drilled in just enough to hit the crack area and open it up but I didn't pop it. Most of the time I don't drill because I guess I'm lazy. I only drill when I think I need to.

I found the batwings are easiest and quickest ones for me to do. The batwings usually don't run but last time, I had one with sharp corners on each end that ran about 1/4" on me on one end.

[Chips_Away_Windshield_Repair]

GlassStarz I totally agree with you on drilling and creating bulls eyes. The only time I do this is at the end or ends of cracks.
I was able to very nicely repair someone elses super glue application in the center of a star last week which had four legs takin' off from 1/4" to over a half inch.
Four drill holes, (.024 burrs) and bulls eyes of appox. 3/16th.", each filled back into the center, cured, polished, the only evidence of a previous attempt was the yellow spot in the very center.

[paintlessplus]

Sorry to hear about that crack out Mike- kinda an expensive education You were in my thoughts yesterday as I had a combo on a Mazda convertible right in front of the driver but very low, only an inch away from the lower w/s moulding. This one had three 1/2 inch legs and I felt that if ever there was a candidate for a crack out, this was it. I explained the process and had the owner convinced that this may be a crap shoot as best and asked him if he wanted me to proceed. "It looks like I've got no other choice than to let you try or I'll have to pay my deductible for a replacement... Go ahead try to save it for me." I was afraid to drill, and the impact point was pretty small. I put my delta bridge over the chip and tightened the injector only about an 1/8 of a turn to start. I then did the same with the rear legs. When I filled the injector with resin it started to weep out from under the seal. I then slowly tightened the rear legs until the leakage stopped. I worked this thing while gently flexing both inside and out for 55 minutes. I never counted the pressure and vaccuum cycles, but there were many. I used a magnifying glass to check the progress -the legs were slow to fill , when I stopped making progress I would gently increase my flexing pressure ,but I was extremely patient. The completed repair was remarkable The customer was very happy I came away looking like a hero because I had painted such a grim picture before I started. I also had him sign my release/invoice before I opened my tool kit. This method might not work well on cold calls, but it sure does on insurance refferals. Bob

[MadMike]

Paintles, you explained that very well so that next time, I'll know some extra tips and tricks in my hat to take it easy, be patient, and hopefully do a great job. Thanks for sharing some of the steps you went thru.

[GlassStarz]

Heres a first for me I got a call from one of the little used car lots I do he had one sold that I needed to fix to seal the deal. This guy usually doesnt want me to stop in he only calls when he needs to do one for the deal and then I get to fix whatever else is on the lot while im there. One of the cars was a new beetle had 2 bullseyes about 1/4 inch apart in lower passenger corner joined by a small crack I figured fix one bull without drilling if the resin runs thru the crack great if not drill the other and get it from that side I sprayed a little water on the suction cup stuck it to the glass only to see 3 cracks run from the passenger corner all the way to the drivers side they actualy went faster than I could see and made a noticable POP!
Now ive had cracks go from pressure and cracks go from the drill but never the suction cup!
Just when you think you have seen it all you see a purple headed goat wearing yellow rain boots crosses the road being led by a pygmy in a tux

[screenman]

Glassstarsz I have had this exact thing happen to me when I tried to repair a screen on a car that had just come out of the spray booth, This was years ago before we had even heard of cooling down. It has not happened since so it must have taught me something.