Outline around repair?

[kingmonkey]

I did a repair for a guy the other day which, I feel turned out to look pretty good. But there was a problem. The ding in his windshield was about nickel sized and had a lot of little cracks in the center, and a lot of black around the edges. The owner of the car informed me that it had been there for at least a year that he could remember, possibly longer. Anyway, I went ahead and did the repair, curing under pressure, and when I was done all of the little cracks in the middle were gone.

However, when I was done there was what I can only say was an outline around the repair. From what I could tell it followed the break nearly exactly. I've seen these before but not nearly as noticeable as on this one. What could have caused this? Did I use too much pressure? Or was it because the break was so big or perhaps a lot of dirt in it?

[GlassStarz]

Sounds like a daisy
They are caused by resin pressured into the pv layer around the break. You will get them when glass is hot more often than not I have noticed when you use a thin resin when its hot you see this more often. The way I avoid a daiy is wipe the ouside of the glass with a alcohol solution to bring the temp down go slow with the pressure when filling rathe rthan trying to hurry things. For myself I like a thicker resin when its hot
Other times a Daisy will appear when to much pressure is used
The other thing it could be is you just didnt fill long enough and when the resin cures it left a air ring on the outside of the break I like to pressure cure and find this eliminates the ring

[Brent Deines]

The age of the windshield and the extent of the damage are also factors, but I agree that heat and pressure are two of the primary reasons for flowering or the daisy effect.

I however would not recommend putting alcohol or any liquid on a hot windshield. I prefer to simply shade the windshield and use less pressure. Although we sell higher viscosity resins for those that prefer them, I use the same resin year round.

If you are leaving a ring of air it isn't due to any of the reasons mentioned above, it's because you are not getting the break properly filled. While curing under pressure may mask that problem, it will not change the fact that the air remains in the break.

I rarely cure under pressure and have no problems with leaving air around the edge of the break, but once again, if you are not using the same windshield repair system I am, curing under pressure "may" be necessary. I'm not saying it is necessary, I'm just saying you should not "have" to cure under pressure if the break is properly filled. If you search previous threads on the curing under pressure topic you will find my arguments for not curing under pressure, but your issue sounds more like.

[Nomad]

I've had dark rings around the edges of bullseyes that were really old after a repair because of contamination. If this is what you had then there really isn't anything you can do to get the contamination out before you fill it. You just have to let the customer know that old breaks like this can sometimes have this happen.

[kenb81]

Maybe it was the glass itself. Was it a chevy product like a venture or a montana? These windshields have a tint on them and if the chip is old (over a year) the chip may develop a ring around it and unfortunately you cant get rid of it

[kingmonkey]

Maybe it was the glass itself. Was it a chevy product like a venture or a montanna? These windshields have a tint on them and if the chip is old (over a year) the chip may develop a ring around it and unfortunatly you cant get rid of it

It was a 1998 Jaguar. I've had this happen before but it always seems to happen on a bullseye and even then it wasn't as noticeable as this one. I wish I could describe it better. You'd just have to see it. I'm thinking it was just contaminate in the break. I don't know really.

[Brent Deines]

It is possible that it is contamination, but if the ring goes around the entire perimeter of the break I doubt it.

A ten year old windshield could very easily be starting to de-laminate. I have replaced many windshields in that age range that had serious de-lamination issues around the edges, and have found that when repairing a chip on those they are much more likely to flower.

I have even had a few windshields that have flowered out several inches around the break, although they were on windshields that were probably 20+ years old and had serious de-lamination issues around the edges.

[GlassStarz]

The shade may work in places like Oregon but when the outside temp is 100 plus shade will only bring temps down to that and turning on the air inside often isnt enough I find a dilluted 20% solution of alcohol works for me I spray it on a paper towel and wipe the glass
It Works for me
The othe option is turn on the air and putt a big towel over the area it will keep the heat outside from keeping the air from cooling both layers. A combo of all these will work well

[Brent Deines]

The shade may work in places like Oregon but when the outside temp is 100 plus shade will only bring temps down to that and turning on the air inside often isnt enough I find a dilluted 20% solution of alcohol works for me I spray it on a paper towel and wipe the glass
It Works for me
The othe option is turn on the air and putt a big towel over the area it will keep the heat outside from keeping the air from cooling both layers. A combo of all these will work well

I started in Eastern Montana where we got plenty of 100 plus temperature in the summer, and still found no need to use any liquids. Just a difference of opinion I guess.

I know the glass temperature is much hotter than the air temperature when the sun is beating down on it, but it also seems that the glass is cooler than the air temperature when it is shaded. I can't say I have actually done any testing to prove that one way or another, but it sure feels that way. As long as it is shaded I don't have any problems with the glass being too hot, but I agree that if possible it certainly doesn't hurt to run the air, or at least roll down the windows to allow the inside of the car to cool down, and I agree with placing a towel or an extra hood protector over the glass prior to starting the repair, and leaving it there throughout the repair process.

My reasoning for not using anything cold on a hot windshield is that my experience has been it can cause the glass to crack if it is already damaged. I've seen that happen mainly when I owned my pressure wash business, and had no choice but to spray cold water on hot glass, but I even had one experience when I put cold resin on a hot windshield and it instantly cracked all the way across. I have also received a number of calls from customers who have cracked windshields by placing wet wet towels to cool the windshield.

Obviously that has not been your experience, so maybe it is just my dumb luck. It sounds like you use a bit of caution with your method so I'm sure it works just fine, but it still makes me nervous.

[GlassStarz]

I use a IR temp thermometer I bought at radio shack when it gets near 70 I do the repair