Appling Heat Inside

[Layne]

I know that I will catch a lot of flak for this post but here it is anyway.

Today I was called to repair 2 chips on a Dodge pick up. One was a "bat wing" type and the other a star. There were legs extending from both. I drilled and lightly tapped to form a mini bull....not really a complete success but striking harder might just extend the legs. I drilled through the outer layer on the one with the longer legs. I then started injection and vacuum cycles and observed that the legs were not filling completely. I then applied heat to the inside of the windshield (wafting the flame back and forth) directly under the injector (and adapter) until the glass clouded over. I then cleaned the cloud away while observing the decrease in the width of the legs. When the legs were about the width of a spider's web I ended that procedure.

I am aware that some of the experts in here frown upon this procedure but it works for me. Make no mistake about it, I do appreciate all of the advice that is posted in this forum. As an additional note, I use the Bar-B-Que lighters that Wal-Mart carries.

OK---I'll note the stones thrown at me by those that disapprove of this procedure.

Layne

[GlasWeldTech]

Hey Layne,
Whatever works for you and you are happy with. I just hope after the glass cools down that the legs don't SHOW back up as in expand and contract. My self I don't use heat at all. But I also have put my injector tripod on glass upside down and filled a break just to prove a point. Hey it worked for me!!!!! I say to each his own as I don't think anyone here claims to know it all.

[pbaker]

If you are asking about how much heat to apply, you just want to apply enought to where the glass (on the inside) is the same as your body temp--mabey a little warmer but not hot, and make sure you let the glass cool back down!! otherwise you could have problems down the road. Hope that helped!?

[SGT]

Layne,

There are no chip repair police out there so if you feel confident in your skills to produce a quality repair then have at it. I don't think most here would beat you up but would suggest some food for thought, what you do with it is another story.

We only use heat to keep the windshield between 70-90deg if needed. As GWT mentions, and we agree, you will have expansion and contraction issues that might lead to a false sense of being repaired(try a practice one and let it cool down). To much heat also could give you a watery look.

Based soley on what you posted, I think you should practice your drilling and poping mini's. Practice never hurt anyone.

Good luck

[GlassStarz]

heat opens the legs some of the mfgs show the match trick in thier videos thats where I learned it every so often I use it I drill one in 15 maybe heat one in 100 but the time comes and you recognize what is needed and you cook em thats where experience comes in

[GlasWeldTech]

Glassstarz,
SO you heat this leg under pressure?

[tooldini]

I always thought that heat would cause the legs to close and make them appear filled. I have heard of using it to help pump some air out of the legs. If I ever us it it will be to help pump some air out of the break.

Jeff

[Sneck]

While we are on this subject, here is a copy of a previous post I made in another thread...


Hey guys,... up for a little experiment???
Allow me to demonstrate how the heating and cooling of the broken glass effects the air and resin in the damage...

First of all, fill your bathroom sink full of water. Then put your hands together (palms together) as if you are about to pray (but hold your hands about 1/2" apart from each other so there is a 1/2" gap between them). Now completely submerge your hands in the water. At this point, think of the water that is between your hands as resin, and your hands represent broken glass. We know that applying heat to damaged glass swells the glass - closing off the damage (forcing any air and resin that is present in the damage out). When you apply heat to the broken glass, it can swell shut so tight that the damage appears to be filled, but don't let that fool you. Now press your hands completely together to represent heated glass that has swelled shut. There is no water between your closed hands... right?... in other words, there is no air or resin in the break because the damaged glass is completely swelled shut.

... Now what happens next is quite magical.

Notice how pulling your hands slightly apart draws water back in between your hands. This is exactly what happens when the glass cools, it contracts drawing resin into the break.

And there you have it folks!

I hope my demonstration has been both informative and enlightening. Thank you all for attending.

[screenman]

GlassStarz,
The break will only expand for a very very short while and then contract closing the legs which is a great way to help any trapped air out. Always allow to cool and always flex the glass slightly once it has cooled. You wil be suprised how even when cooled those heated legs will stay shut. Try it on your practise glass.

The manufacturers show this trick to make it look like they can fill a chip in 5 minutes they do not show you what the repair looks like 10 hours later. How do I know this, becuase in the early days we did it ourselves.

[kenb81]

No need to heat just flex each leg independetly until full