Air sucked into crack repair

[shermfiddle]

Today I repaired a long crack. Looked great until I slipped on some Ice and braced myself on the windshield that I just repaired. I had NOT cured it yet but as a result of pushing on the glass I saw several air bubbles in my repair. I tried re injecting again to push the bubbles out of the crack...that didnt' work, so then I thought it might be a good idea to place heat on the crack thinking that the crack would contract and push the air bubbles out...that didn't work either. I didn't charge the customer even though she wanted to pay me for the repair When I'm not happy with a repair..I don't charge anything and that has been my policy for 13 years. I would like to know how you guys get the bubble out of crack repairs in case I fall on another windshield again.

[screenman]

Did you have the part that was filled covered with wet curing tabs, by this I mean you had put a nice line of resin on top of the crack up to the point it had filled and placed a tab or tape on top. As for removing any air bubbles, I tend to slide the injector along the break, although I do not think this is the Delta method. I also understand your thinking behind the heat part, again you would need wet tabs/tape over where you want the resin to pull in.

[Chips be-gone]

screenman

I think his issue is that he slipped and used the windshield as support and that is what caused the glass to flex and trapped air in it.

shermfiddle

As you are doing cracks, you need to cure it as you are filling it. even if you do a short 4" run and cure it then move on... I tend to keep the light behind my cracks by 4".

What system and resin are you using? Some resins set faster that others so the resin does not have time to flow back and cause air traps also.

If you are working in the snow or on an icy surface try to carry a carpet sample with to stand on for traction.

[screenman]

I am aware of the situation, it is just that is he had the crack covered with wet film this would not have been able to happen, as when the crack opened the only thing that could have got in was more resin. As for curing as you go I would certainly not be doing that, however if it works for you then that is fine.

[Chips be-gone]

. As for curing as you go I would certainly not be doing that, however if it works for you then that is fine.

Please give me your professional advise why one would not cure as we go. I am all ears on your take on this.

[screenman]

Simple I can slide an injector and fill a 12 inch crack in minutes if it is cleaned and prepped properly then using 2 or 3 lights I can cure it in a few minutes job done. I cannot see any benefits at all in curing a bit at a time, I would have thought you are leaving the door open for more air each time you manipulate the tools required to do it in sections. I have of course in the past tried your method but have found it not to be to my liking.

[Chips be-gone]

I am not manipulating the glass and moving parts around to make the glass to flex. I am having the UV right behind while I am filling.

If a crack is vertical and wide open, I will do a 4" or more and cure it so the resin does not flow out, then work my way up traveling with the light as I go. Horizontal does not need to be done in sections but I do cure as I am filling.
It takes not more time to slide the light as I am filling.

I guess we each have our own way of doing cracks.

[screenman]

That last sentence is bang on, as I said earlier if it works for you do it.

[shermfiddle]

Thanks for all your advice. I did have my tabs over the repaired crack. The idea of curing as you go along is probably a good idea. I'll try that next time I repair a long crack. I am confused as to the viscostity of the crack resin I'm using. I am presently using Delta Megni Bond Resin. I use to use Janvil who is no longer in the windshield supply busienss. I loved that resin. It really worked very well. I am very hesitent to use just any resin. I believe that the refraction of the finished product should look good and not shine like cheap resins that are out there. It would be interesting to find out which resins work best for everyone. I do like the Delta resin at the present time. I'm not sure what the long term results would look like a year or two from now? I hear the liquid resin green cap is good too. Thanks for the advice...I will try to cure as I go along with my slide injector and also be careful not to lean or "fall" on the glass.

[Chips be-gone]

You did ask what resins some of us use for cracks. My choice is Glass Technology CR. Over 15 years doing cracks and I really do not know of any calling back on a crack failing, maybe verry few expanding past the crack, but not reopening..