Todays Repair

[zlm_us]

I did a repair today and every time I would remove the injector I could see air in the break. I decided to pop it and finally it filled. I guess I should have popped it first. Well when I finished the repair I put the pit filler in and cured. I then noticed a small little ring around the drill hole. Is this from air in the pit or a dull bit. When I drilled, the bit drilled with no problems and did not seem to be dull. The top pics are before just differant angles to show the legs.

pictures

[GlasWeldTech]

Looks like drill bur marks to me. Kinda like a dull or not sharp bur, but not a bad repair in all. Your pit filler will hide a drill hole IF it isn't burnt from a dull bur.

[CV Windshield Repair]

Sometimes when you tab a repair that has been drilled you will get a tiny air bubble trapped in the drill hole. You need to pull your tab off before you cure and remove the bubble by using your needle and a drop of resin. When you replace the tab try to roll it on, sometimes when you place it on the windshield quickly it will pull air back into the drill hole. Your picture appears to be a tiny air bubble.

[Brent Deines]

I wish everyone who called for tech support would provide pictures like that. I agree with CV, to me it looks like air in the resin.

Did you use pit resin? If so, air bubbles are often contained within the pit resin and introduced into the break when the pit resin is applied to the break. It is often hard to detect until cured. We recommend storing pit resin bottles upside down prior and during use, never letting the air into the squeeze tip. Since I started doing this a few years ago, I have had very few completed repairs with an air bubble at or near the surface, or in the drill hole, but it does take a little practice to keep the bottle upside down while you remove it from the tool box, unscrew the cap, and apply a drop to the pit.

If you do not use pit resin, it is very possible a little bubble of air was trapped when you applied the curing tab. The pit resin eliminates that problem when properly applied, but compounds the problem if there is air in the resin itself.

I agree that overall it is a good looking repair. If I am correct and what you are seeing is a bubble at or near the surface, you may be able to stick a thin needle in it to open it up, and then fill it with a low viscosity resin that will flow easily into the small area, properly wetting all the surfaces.

If it is an air bubble that is farther down in the drill hole, you may need to drill it out again with a small bur, like a 169L, and re-fill the drill hole a low viscosity resin, then cap it with a high viscosity pit resin, making sure that there is no air trapped in the drill hole, under the curing tab, or in the pit resin.

Any time you drill you increase the chance for an air bubble, and make it more difficult to restore the cosmetic appearance of a break. I rarely drill these days, and find that my repairs look much better overall. That said, there are times when drilling is necessary, and I will not try to second guess your decision to drill based on a photograph.

If I am wrong and what you are seeing is marks from the drill, my suggestions are a waste of time, and you are better off to leave well enough alone. Although your picture is awesome, I hesitate to state too emphatically that I know exactly what caused the problem. I would need to see it first hand for that.

Good luck, and keep doing the great repairs.

[zlm_us]

I appreciate the information. I did use pit filler I almost feel like it was an air buble, because I usually can tell when a bit is going dull. The customer was happy with the repair and I was happy to see the legs come out as good as they did.

[gt_repair]

If you used the pit filler right away and put it on the repair before the injected resin started to cure then the pit filler and the resin that was injected will seperate and cause the air bubble. You need to PRE cure the resin first then aply the pit filler.

[Brent Deines]

GT, I disagree. I have never pre-cured the resin before applying the pit resin, and I have never had the problem you describe, which is not to say that the method you use does not work equally as well.

The resin and equipment used can also be a factor in the method that is required.

ZLM, The legs filled in very well, and the is the critical issue. You obviously take a great deal of pride in your work, and have every right to from the picture you sent. I love to see people as anal as I am about how good their repairs look.

[shermfiddle]

It looks like you may have burned the glass with your drill bit? But over all that's not a bad looking repair. Good job.

[sunshine wr]

The method that gt repair describe's is the method I was taught by Dave Shores when he was @ Glas-Weld. This procedure works some of the time, but, I get more consistant results by first: putting pit resin on and curing without a cure tab, second: slicing (blade @ 45 degrees) the pit resin off(it will be wet on top cured underneath) and then apply pit resin and cure with tab as usual. I only do this on drill holes or when I foresee an air bubble problem i.e. large or deep pit area.

[Brent Deines]

I recommend scraping the pit resin at a 90 degree angle, rather than "slicing" at a 45 degree angle. This will produce a flat smooth surface, and there will be no need to the extra step of the 2nd pit filler application.

As for the resin not being cured under the pit resin, I would not be happy with that. I recommend a cure time of 5 minutes so you can be assured that the low viscosity resin under the glass is cured thoroughly after the first and only cure, not just the pit resin.

Remember, most low viscosity resins cure slightly slower than high viscosity resins, and nearly all windshields manufactured today utilize Solar Green or similar glass which blocks a percentage of the UV rays used to cure the resin. It simply is not enough to cure the pit filler cap.

I also believe that it is best to remove all the air, including any bubbles in a drill hole prior to curing, and it is not all that difficult to do so in most cases.

I assume that you cure the resin under the pit filler cap thoroughly on the second cure, so I am not trying to be argumentative Sunshine. I just don't know why you would want to do the extra step when you don’t have to. Dave and I have talked many times over the years, and although we disagree on certain techniques, I think one thing we do agree on is that all the air needs to be removed from the break. If you are getting that done, the finished repair looks good, and the finished repair cannot be felt when you run your finger over it, then you and I are simply taking different approaches to the same end. If time is not a factor, then taking an extra step is just a personal choice.

Again, some techniques are system specific, which is why I always suggest training from the manufacturer of your equipment first. For instance, we seldom drill or cure under pressure, but I have been told that with some systems that is the only way to get the break filled properly.

If you find that your repairs are not coming out to your satisfaction, or your customer's satisfaction, then you begin your search for alternate techniques. Most importantly, you want to make sure your repairs are better than those of the competition, or at least that has always been my goal.

It’s all about the results.