My personal update and more questions!

[jonnyques]

To all that have answered and inputted to my questions I thankyou. This is a add on to my PDR business, and I'm enjoying it. I find myself now looking for windsheilds to do. Poping Bullseyes The other day I practiced on a car going to the wreckers. I did 16 pops tring different things. I used a FG2 bit. Holes drilled shallow were hard to pop and often had a crack with the bullseye. Drilling 1/2 the depth of the "pear of the bit" produced good results. Drilling the whole "pear" (not hitting the laminat) produced the best results. All bullseyes were aprox 1/4" in dia. I also found you need to pay attention to the angle of the probe when striking it. You want to keep it 90 degrees to the windsheild. cracking seemed to happen when I tried it at different angles (just wanted to see what would happen if I didnt pay attention when doing this). I found the bit was junk after doing all this drilling. I was just using the drills own weight for preasure, would rill aprox 2 sec. lift to clear hole, then drill 2 sec etc. Would the life of the bit be shortened because this was undamaged glass? I figure a brake would have fragmented glass which may ease drilling? Im just wondering if 16 holes is good or should it have lasted longer. Cleaning winsheild priour to repair. Do you guys clean a windsheild before a repair? I have noticed on some windshelds that after removing my tape, the cured resin will just peel off the glass. I dont know if its from the car was soap or another product. If you do clean what do you use. Ive read about the acitone / alcohal posts so what do you clean with? Lost my first windsheild I sure it was bound to happen and will make me more awred of it in the future. I was doing a small star. The glass was quite hot so I put the airon in the car, full in defrost. I waited till the glass temp droped then started the reapir, I had the air now off. I think I was in the second preasur cycle and noticed that part was not filling. I tried flexing with no improvement. My thoughts at this point is the glass is still to hot and the leg is closed up. The glass did feel hot. So I put the air back on full defrost. The bridge was still on and in the preasure cycle. Can you say "now ya see it now ya dont't?" or rather now you dont see it now you do! All seemed ok for a few minutes, then there it was a foot long crack. So where did I go wrong? Was it the cooling with the air? I have to think so. Do you cool with air? Do you only do it with the bridge off and then not cool anymore with the air? I read of guys saying they use a alcohal / water spray? I was woried this could put moisture in the brake. Do you just sheild the glass and waite? I know this is one area I have to put more thought into as I feel this was the reason for the crack out. O if you wondering the customer wasn't upset. He knew it could happen. Lastly (for now!) Star breaks I have noticed that when doing a star a leg may seem to grow, cracking out as you flex the leg to get it to fill. I just stop flexing it and now cure under preasure(thanks for the info on that one!) Do you ever drill and pop one of these growing legs or do I just leave it alone. Thanks again to all
John

[ruffburr]

something i learned the hard way, Don't use the a/c on the defrost mode! run the a/c on the recirculate mode, be sure your shaded, let the car run windows up till it cools down throughout the car, open the windows a little to balance the temp with ambient temp, do your repair while the car a/c is running & don't apply to much pressure with the injector i've been working in 110 degree heat and after losing two windows i've found that i haven't had a problem since i've been doing it this way. Just my nickels worth.

[GlassStarz]

Your right shade the glass then turn on the air with heating the outside layer with the intense sun and cooling the inside layer at the same time with the air then adding pressure from your injector into the break your asking for trouble. Just way too many things going on with the glass shrinking on one side and swelling on the other you gotta be doing somthing like shade or alcohol on the outside too or POP!!

[gold star wsr]

I tried something recently that I saw suggested on one of the forums... (could have been this one, but I dont remember): Instead of applying a cooling agent to the outsid of the windshield, I started the cooling process from the inside of the glass. Of course this requires access to the inside of the vehicle, which is not always possible. I keep an air temperature (not cold) solution of alcohol mixed with water with me to use for this purpose. With the windshield shaded from the sun and the windows open, I dampened a cloth with this mixture, and continued applying it to the inside of the glass until the temperature was to where I could proceed with the repair. Why use alcohol and not just plain water? The reason is because alcohol has a faster evaporation rate, so the cooling is accomplished faster. Because the inside of the glass is not broken, there is less chance of shock causing the chip to run. This worked very well for me, and I plan to use this method whenever possible.

[Mikedoby]

I agree with Gold Star on using the alchol / water mixture to cool down the windshield from the inside. I keep a spray bottle of this mixture in my supply box and will mist the inside of the windshield if the temperature is too hot to the touch. I might also mist around the damaged area on the outside of the windshield if I feel that additional cooling is needed. Either way the alchol / water mixure does a good job. By the way, I usually use between a 30 to 40% alchol mixture.

[screenman]

Has anyone ever found that alcohol damages the dashboard if spilt. We do not very often have to cool down a screen its just been raining for about 40 days over here. and thats supposed to have been our summer.

[gold star wsr]

I dont spray the solution directly on the glass, instead, I moisten a towel with it and apply it that way...seems neater to me. If you are going to spray directly onto the glass, then first put an absorbent cloth on the dash to prevent any of the liquid from getting on it.