Connect the manifold gauge set as discussed above. Connect the yellow hose to the can tap valve and windshield chip repair seat (turn clockwise) the valve. Close the blue gauge on the manifold gauge set. Open the valve on the can tap valve. Slowly open the valve on the blue or "low-side" gauge and let the refrigerant flow from the refrigerant can into the system until you see a reading of 60psi on the "low-side" gauge. TIP: Placing the refrigerant can in a pan of hot water will allow the vapor refrigerant to enter the A/C system quicker. WARNING: Do not invert the refrigerant can. Doing so will allow liquid refrigerant to enter the system resulting in a ruined compressor.
If the crack looks exactly the same when completed, it's very likely the technician didn't inject the resin properly. A properly completed repair with cause each area of the damage to disappear from at least from one angle of vision (ex: looking from one side, looking from below, looking from above, etc.).
Even if you only drive on surface streets, the occasional rock or piece of debris can hit your vehicle's windshield and leave a mark. If you travel often on the freeways, it can happen much more frequently. If a piece of debris creates a minor chip in the glass, it may not cause a serious problem. However, if a crack develops, it can travel and grow larger. Eventually, it may even become a safety issue. Contact a windshield repair specialist and have the damage fixed.
"But it only takes one person to do what is right - the power of one," answered the boy with a big grin on his face. He held up one finger for his fix auto glass repair grandfather to see.
There are various ways in which the glass can be damaged. The windshield is made and kept under high stressed areas when fitted. Plus it has very high density. Because of this, even a small crack poses high danger for the glass. Ignorance of even a minor vein in the glass leads to damage.
Windshield cracks and blemishes can be troublesome. You can never really guess what is going to happen; they almost always start small and end up spider webbing across the remaining windshield. Some rock blemishes only leave chunk of glass missing. If not treated correctly it can turn into a large crack as well.
I want to congratulate you on your decision to start a windshield repair business. It can be a fun journey and profitable experience with the right guidance.