Am looking for advice on drilling glass. I have a crack in the windshield of about a foot from the right upper portion extending downwards. It is only on the outer portion of the sandwich. I was considering drilling a small hole just at the end of the crack. I bought a set of diamond bits but am leary of starting, Since it is safety glass it is unlikely that the entire windshield could crumble/ disintegrate. Since I have never drilled glass before I am curious as to how it may go. I have gone to a site that describes how easy it is with the proper advice and warnings. I also went to a local glass repair shop and said he wouldn"t touch a auto windshield. ( he probably had some liability issues ) He also warned me "not to touch it, as I'll screw the whole thing up" He did not apparently realize it was already screwed up. I am of course only interested in containing the crack from growing. If anybody has any personal real experience with drilling glass I would be most interested. Please, no opinions or advice, only real experience! Thanks much. :cheer2:
I had a NOVUS repair guy do 2 windhsields for me and they came out very good, but they were on older cars.
Thanks for the tip, no Novus dealer in this area. I ended up drilling the hole myself and was amazed just how simple it was. Now I have to wait and see if the crack stops growing.
To do it properly you need to evacuate the air from the hole then inject UV curing super glue. It is difficult if the crack extends beyond the seal of the screen. If you don't evacuate it first then there will be a bubble at the bottom of the hole and the glue will not be sucked into the crack. Given that you have made a pretty good job of stopping the crack (probably) then I would just super glue it then use a scalpel to remove the excess and polish it. It aint going to be perfect but it should work. All kinds of things are possible but the more you mess the more risk you run of trashing the thing.
I definitely agree with your last paragraph. I did seal it with superglue ( the two holes ), the initial bullet,and the newly drilled hole. Thankyou for the reply.
Unfortunately, no real experience doing this thing, other than on products and glass other than auto glass. Drill-stopping the crack hopefully eliminated the spread of the crack, but since you haven't gone all the way through the glass, there are going to be some "funny" stress points here and there. You may wind up with a lower or intermediate layer starting to crack and spread from the drill stop, or somewhere else along the existing crack. If you didn't run something like acetone or lacquer thinner in the crack to clean it - you might have problems. Acetone cleans, but more importantly, disperses and dries up any water that might be in the crack. Water is your real enemy here, as freeze/thaw action will cause problems (maybe not so much in Sacremento, but other places could be a real problem). The superglue probably won't last for long. Cyanoacrylate glues have extremely low shearing strength, so I'd expect this to flake off with the flexing and stress that occurs for the windshield. Also, the general run-of-the-mill cyanoacrylate glues are not recommended for glass, there's special varieties for use with glass (not sure, there may be other formulations for tempered vs. untempered glass as well). Since you didn't evacuate/purge the air, there's probably still some air trapped in/under the glue. Variations in atmospheric pressure may give you some trouble in also causing the glue to flake off. In other words, don't drive up and down the Sierra Nevadas frequently. I don't know that normal weather barometric pressure will be enough to cause a problem, but .... Honestly, the glues the autoglass guys use is much better suited, and they have the other equipment to evacuate most of the air to assist in the glue actually getting into the crack/chip and bonding with the glass. They aren't perfect either, and if not done correctly can still pop out, but generally much better suited for this type of work.
Tundrwd, Thanks much for all the tips. The main reason I tackled the job was that no repair shop would even approach a crack of 12" or more. My windshield crack is 15". The top glass seems totally flat/ level with the under glass. Later when it warms up I'll try to use some of your suggestions. If worse comes to worse I can always have it replaced for about $250.00. Dealer wants over a thousand. Have not been over the Sierra since the crack grew, good thing maybe. Andy
There are "windshield repair" kits that basically give you a tube of cyanoacrylate, a syringe, and a suction cup. The idea is that you clean the area around the hole or chip, attach the suction cup over it with adhesive to totally seal the edge, and load the syringe with the glue. Attach syringe to suction cup and pull *up* to evacuate the air, letting it bubble through the cyanoacrylate. Hold that way for a couple of minutes, presumably to let any remaining water vapor boil off or whatever, and then slowly release and then push, shoving the glue in to replace the vacuum. . Or something like that. It's been years since I did this to stop a little "star chip" in a previous car's windshield from spreading. I caught it pretty early, and the fix did seem to fill the void and stabilize everything well. . _H*
Yeah, something like that may work, if using the right glue, but from what the OP said, the crack is WAY too big for any self-repair kit I remember seeing. Probably why no one would touch it. Simply too big for their equipment to attempt a repair.