Stopping A short Crack

[All-Clear]

How's it going forum members. Hope business is well for all of you. I have a quick question on terminating a crack. How long should a short crack be before putting a bullseye at the end of it? If the short crack is 1 inch, should it have a bullseye at the end of it? Any info would be greatly appreciated, thanks.

[screenman]

I am finding this one hard to answer as all breaks are different, I would though be very unlikely to drill a 1 inch crack without first testing it by flexing. Many factors come into play, position on windshield being one of many, type of vehicle another, old damage, very wet damage etc.

[EMCAutoGlass]

Generally, a crack/leg over 2-3" will need to have the tip drilled and a small bullseye tapped. I run the corner of a razor blade over the leg, and if I hear it click, I know it has surfaced and I'll drill/tap a bullseye. As stated previously, it's a case-by-case basis.

[All-Clear]

thanks for the info screenman and EMCAutoGlass. I'll take your advice into consideration when I come across a crack again, thanks

[kentcrossfit]

So, you guys don't tap a bullseye unless it's surfaced? So if you see a 2-3 inch leg coming off the impact point do you still at the very tip of the leg and tap the bullseye? Or do you drill the 1/4 inch past the leg and then tap the bullseye? I've heard some people drill slightly past the leg and then tap the bullseye to let the leg connect. Because I've been experimenting on my practice windshield and most times when I drill at the tip of the leg and tap the bullseye the leg goes right through the bullseye and extends through the other side of it (the bullseye). So then I find myself just having to keep drilling and tapping bullseyes in hopes that eventually the bullseye will catch the leg. From what I've seen I'd avoid any chip and I would do everything else before tapping a bullseye because It seems like it just extends the legs...

[kentcrossfit]

So, you guys don't tap a bullseye unless it's surfaced? So if you see a 2-3 inch leg coming off the impact point do you driill at the very tip of the leg and tap the bullseye? Or do you drill the 1/4 inch past the leg and then tap the bullseye? I've heard some people drill slightly past the leg and then tap the bullseye to let the leg connect. Because I've been experimenting on my practice windshield and most times when I drill at the tip of the leg and tap the bullseye the leg goes right through the bullseye and extends through the other side of it (the bullseye). So then I find myself just having to keep drilling and tapping bullseyes in hopes that eventually the bullseye will catch the leg. From what I've seen I'd avoid any chip and I would do everything else before tapping a bullseye because It seems like it just extends the legs...

[screenman]

Kent I would say you are tapping to hard and not drilling deep enough, maybe the Delta depth gauge may help. I did not say "unless it has surfaced" I said each one is different.

One thing to keep in mind is that a practice windshield on a stand is way less stable than one still bonded into the vehicle, so a crack out is far more likely.

Should a crack jump a small distance past your stop mark do not worry too much, as the resin will hold this together as it would in a small starbreak, the stop has still helped along the way.

I seriously like the way you are getting practice in and commend you for it, too many people go from DVD or training straight to customers cars.

[kentcrossfit]

Kent I would say you are tapping to hard and not drilling deep enough, maybe the Delta depth gauge may help. I did not say "unless it has surfaced" I said each one is different.

One thing to keep in mind is that a practice windshield on a stand is way less stable than one still bonded into the vehicle, so a crack out is far more likely.

Should a crack jump a small distance past your stop mark do not worry too much, as the resin will hold this together as it would in a small starbreak, the stop has still helped along the way.

I seriously like the way you are getting practice in and commend you for it, too many people go from DVD or training straight to customers cars.

Well, I'm a true perfectionist. I want to represent the most professional, competent service that truly brings value to customers. The worst thing in the world that can happen to me is to be approaching a "simple" chip repair and it turning into something that is beyond my abilities. Because I think that if you have a company, and you represent yourself as an expert in the field you should perform repairs in such a manner. I don't want my company to come off as some dude who just found some car windshield repair kit and decided to go try to make some extra money. Because if that's the quality they are going to be getting then they mine as well go buy a 3D Autozone repair kit and do it themselves.

Thanks for the complement Screenman. It's nice to hear that I'm not wasting my time doing multiple repairs on this windshield. I've been experimenting with all kinds of drilling methods and analyzing what is making the crack extend beyond my bullseye. Well, I was doing it like the DVD said (with slow clockwise motions) and then I broke a drill bit so I thought maybe I would try just straight drilling, and well straight drilling was definitely a no go (I had drilled too far using the clockwise motion and hit the middle layer which resulted in the bit snapping). The hole isn't big enough when drilling straight on and puts too much pressure on the edges of the glass (where you drilled the hole, and when using the scribe. Because the width of the scribe is wider than the hole.) making it want to crack further. So I went back to the clockwise motion while drilling and I nail every bullseye I make, which upped my confidence level to where I feel I can confidently service customers, because that was the only aspect that I was really unsure, and uncomfortable with.

Sorry for putting so much detail. I just want other newbies to understand how to terminate a crack and the reasoning behind the motions (i.e. circular drilling). Because if any are like me. They will want to know why they are doing what they are doing rather than just doing it because it's the steps they have been taught.

Nick

If you provide a truly professional service, customers will see value in paying a higher price.

[screenman]

You keep putting the detail in, I for one will keep reading it.

Are you using a slide hammer?

Are you making all or most of your damage wet, before starting the repair?

Have you tried working outside, along with the effects of direct and indirect UV?

Not trying to give you more fences to jump, just giving you more things to learn befre you go out on the road.

Remember, nobody ever regrets buying quality, be it product or a service.

[EMCAutoGlass]

If you are not using the depth gauge that comes with the spring hammer, then I highly recommend getting one. You can get the depth gauge, by itself, for less than $10 from DK. I'm not sure if you are using the spring hammer? I have one and found that when I drill and tap with it, the crack tends to shoot past the mini bull's-eye almost every time. So, I drill straight down with my Dremel (use two hands: hold like a pencil with one hand, and stablize the top with the other), and I use the depth guage to drill to the exact depth every time (works great!). Don't use too much pressure on the drill and let it do the drilling for you, and always flex the tip first to see how sensitive the crack/tip is. I generally drill about 1/8" past the tip. Then, I use a traditional metal striker and needle to pop my mini bull's-eye. Maybe 1 in 10 cracks shoot past the mini bull's-eye since I've switched back to the old-school method. I think the needle I use is skinnier than the tip of the spring hammer, but I recommend getting some wider drill bits if your needle is too wide for the hole. DK has a bunch of drill bits to choose from, and you can call them to recommend a different diameter bit. Use your practice glass and drill/tap, drill/tap.... just to get a feel for tapping by hand. After about a dozen or so, you'll be fairly competent. I always tell a customer there is a chance that the crack will extend during the repair process. When it does shoot past the mini bull's-eye, I repair as if it didn't, then I cover the mini bull's-eye with electrical tape before curing. Then, I go back drill/tap the new tip, fill, then cure. It's not as pretty when there's two drill holes, but I've made sure the tip is terminated in a mini bull's-eye and it's completely filled. I explain this to the customer and have had no complaints. Hopefully this helps a little.
-Marty