More advice please!

[Masterglass]

Jeff, I think we are debating apples and orages. Curing under pressure is for the larger breaks that extend post the diameter of you're injector. The shrinkage will not occur in one area, but throughout the break. This helps hold it in the star legs or very large combo breaks. Fact is you cannot cure the resin directly under you're injector until you come off of it. Mounding the resin is correct, but mostly to avoid air bubbles from appearing in the pit filler. The resin cures from the outside in, which will still trap a small amount of gas in the break and put pressure on the pit filler. You disagree with taking an extra 2 minutes to cure before applying pit filler? Then apply pit filler, cure, scrape and polish. While were on the subject, I have any extra Dremel minimite set up with a polish wheel for final polishing. Alot nicer than with a rag by hand. To the replies saying it is moisture in the break, all the resins I have used in the past will turn cloudy and a little whitish if there is moisture in the break. If it is water, and you have sealed the repair, how does it evaporate from the break? Water will not stay a separate entity from the resin, but will somewhat mix with it.

For anyone wondering, my data comes from doing repairs everyday and I keep a couple of windshields in my shop for testing new resins, techniques and ideas. Each repair is labeled and notes are kept as to what I was trying to test. I keep them over a time period, set them outside to simulate actual conditions. I am convinced beyond a doubt of one simple fact, the longer the break has been on the windshield, the less cosmetic clear out you can achieve. Try it for yourself, create a bullseye or starbreak (doesn't matter) on a practice windshield, repair it and it will darn near disappear easily. Find a similar damage on one thats been there for a least six months and note the difference. It can still be repaired structually as strong, but cosmetic clear out will not be as great. The reason is simple, every time it is exposed to any moisture, when the water dries out it leaves behind whatever contamination was in the water. There is something in the morning dew, rain (road oil) carwash rinse water has oil in it to make it bead before the blowers. Unless you live in a state with no pollution and it rains bottled water, it will effect the repairs.

Delta's resin matches the light refraction factor perfectly, and the acid base help break up some of the contamination, but it is still there in the break and will reflect back some light, which is why it can be seen more clearly. This is why you should always ask you're customers how long it has been on the windshield before giving them an idea of how it will look when you are finished. Remember always undersell cosmetics, so the final repair will exceed their expectations, and you always have a happy customer. And for those who will respond with extremes, let me clarify, if it is a relatively fresh break use 80%, if it's older use 70% etc.

Delta's injector and bridge is excellent. From the stand point of ease of setup, access to breaks, simplistic design, low maintenance and only one seal to worry about, and most importantly, the finished repair, cannot say enough positive. But the biggest determining factor on finished repair is how long it has been left open exposed to the elements. This is why I use Delta's chip savers (cheapest I've found) as bussiness cards. With our profit margin in the industry, we can afford them and it gives your customer a great impression of you. Also, if a chip saver card is in the glove box the next time they get hit, who they gonna call??

[screenman]

Materglass put some resin in water you will see that resin and water can stay seperate unless they are mixed and they emulsify. The milky or cloudy effect is usualy is usualy cause by allowing moisture or air to contaminate the pvb. This can be done by pressuring the water that may be left in the break into the pvb.

Some breaks will start to go milky after a short while and others never at all depends on if the contaminate can actually get to the pvb.

I do agree however that normaly the quicker you get to a repair the better it looks when finished.

Glass when broken does actualy start to oxidise on the broken surfaces but you will need a very big magnifying glass to see it.

[screenman]

Forgot something I did an experiment once I filled a bullseye with water dried just the surface and pitfilled it and did not scrape off the excess this made sure it was air tight, went back to it a couple of days later and it was dry.

Question where did the water go?

To be honest I have not got a clue either it manged to evaporate through the glass, the resin or the pvb but I know it went somewhere.

[DaveC]

Screenman,

Just to get a rise ....

Atoms, the basis of all life, substance, compounds, etc... are in constant, rapid and violent motion.

Check with any physics professor and they will tell you that, given time, even a bar of lead, placed directly next to a bar of gold, will eventually fuse together.

Of course, the laws of physics have proven that gasses and liquids can/do "intermingle" with eachother more rapidly as they are inherrently permeable.

I would suggest, that a true test of water to resin interaction, could not be accurate to the naked eye as both liquids are opaque/clear to begin with.

Try adapting the "Drop of Ink in Glass of Water Test," instead, if you want to assert results based only upon registration of the human eye. Mix your drop of water with some sort of organic coloring, then place a drop of this mixture into several drops of your repair resin and monitor/see how long it takes for the resin and colored water to blissfully wed;)!

Sorry, had to say it and "prove" to my folks that all of that money that they spent on my education would eventually be useful;)!!!!!

[screenman]

Davec I agree the were not scientificaly controlled tests I carried out but if you spend a little time observing what I said and try the experiment yourself I think you will find I am not wrong.

It just goes to show the different sort of people in this trade I got expelled from school at 15 started my first business at 18 had my first car lot at 19 and sold a lot of cars up until I was 33 I then moved into the country and looked around for something else to do, I started screen repair for my son who was coming up to school leaving age and enjoeyed it that much I kept on doing it and I still enjoy it now. Other techs seem to have come from a variation of careers before starting screen repair.

Many people seem to have had a lot better education than I but still end up in the same business one sometimes wonders if school education is as important as it seems.

I am sure this will ruffle a few feathers and hopefully it is not offending anybody it is certainly not meant to.

[Masterglass]

screenman, putting pressure and vaccuum from the injector is more than enough to cause a mixing of the two. Next time you drop some resin in water perhaps you should let it set a little longer. Bottom line, I do what works for me. My suggestions are merely to help others in the bussiness. Take them or leave them, it makes no difference to me.

Yesterday, first customer, 1997 F-150, 5 breaks, bought truck used, clear out 70% max and took longer to fill. My next two customers, each break was less than 1 week old cleared out immediately and were hard to see on the inside. Very happy people.

[screenman]

Could not agree with you more do what works for you.

My postings are just suggestions that people less experienced might like to try or not it is up to them. I try and be as positive as possible but we are all not going to agree on everything.

As long as you are getting what you want out of this business you are doing right for you.

I still feel that water and resin can stay seperate in the break although as I said in my earlier post they can also emulsify.

Moisture is still the biggest enemy in screen repair..

[glassdoctor]

I don't remember what all was argued in this thread, but my two cents is that I also have seen that water does evaporate out of a cured repair. Always.

That's why I have been able to re-do many repairs that were obviously done with water in the break. The cured resin is not vapor proof. Trapped H2O will escape, eventually.

Sometimes, there is still a grey area within the old repair that can't be cleared up because resin can't penetrate it fully. The moisutre can definitely affect the resin in the break, but eventually it's gone, IMO.

And I see that the moisture affects the areas within the break, not just bleeding into the PVB. Often, I see old bullseyes that are not clear. It's not the area around the bullseye that's affected. (PVB)


To quote screenman... "Moisture is still the biggest enemy in screen repair.."

Absolutely.

[glassdoctor]

Just to clarify... you can re-do these old repairs where moisture was a big problem, and there are parts of the break not filled properly due to the water that was in the break during the original repair. Doesn't matter if it's the perimeter of a bulleye or legs of a star, etc...

Weeks/months later, these areas no longer have moisture in them, and they often fill nicely if you cna get resin to the area. If there was still water in there, the same problems would recur.

(And even the grey, milky areas from moisture sometimes will fill with resin given enough time... more evidence that whatever moisture was there is gone...)

There are often still problems associated with repairing "old repairs", but water in the break is not one of them.

And, I'm not saying that water cannot "mix" with resin and mess it up permanently. It separates the resin enough that it can't fill 100%, and can leave a grey or milky look, etc.

But the resin is not water soluable... to bad. If it were, a little moisture would not be a big deal. It would just dilute the resin a bit. Then we could have a special "wet repair" resin made to accept the dilution of the wet break.

Hey Delta, can you get busy with that? I need some of that resin... asap...

[Lee]

Masterglass. "Yesterday, first customer, 1997 F-150, 5 breaks".
I'll bet this windshield is starting to resemble a shower door. A windshield in this condition should be replaced. Where do you people draw the line on telling your customers to replace rather than repair? How about it Delta. What is your opinion on this?