Have looked over all of the aftermarket windshield postings I could find on this forum and want to relate my experience as well as ask a few questions. My 69 roadster had a cracked windshield. The OEM glass in the car fit great. We removed it and had very little rust through so little patching was done. Certainly not enough to cause the frame to lose its shape.

Recently had a local installer install a PPG windshield and it fit like crap. The gaps on the upper corners to the trim were terrible with one over 1/2". Looked this up on the forums and found many advising Pilkington glass and blocking. His comment was he does a few vettes a year and this is usually how they turn out. Why he didn't warn me of this is a mystery to me as if I were him I would have. He also advised that even if you block them they may fit better but will probably crack as blocking them puts stress on the glass and that is why they don't block them.

Second installer does lots of vettes and classic cars and had him bring out a Pilkington. At dry fit he didn't feel it would install well and would probably crack if it was blocked. He said this is normal with these cars and advised he would come back with 2 other windshields from other sources and see if he could find a good match. Am waiting for him to call back.

Even though I have already installed a new top and rebuilt the top frame, if I have to I can certainly reshape the top of the frame but there are limits as to what I can move without messing with the tops front bow fit.

My questions,

1. Anyone else had this much trouble? If so what did you do to solve it.

2. At the time of your install with the top corners tight on the frame what kind of gap did you have at the center and once blocked has it cracked and how long has it been. On the Pilkington mine was about 1/2" high at the center of the top.


Thanks, Mark Smith

 

i did mine on my 72 just recently and it was not bad at all. I used Pilkington glass and am happy. We did not block it and we used urethane. Something doesn't sound right with your frame, do you have any pics?

Sully

 

Sully,
No don't have pics and no glass to show gaps, just the measurement I took when the second installer was here with the pilkington. I also took some measurements off a 70 and my frame isn't off that much from that. no differences greater than 1/8" That is why I was wondering what gap others had at top center from the sealing area of the frame to the back side of the glass with the top corners resting on the sealing area. If the original glass fit was poor and top frame fit was off, I would question the frame. But that's not the case. One of the other vette forums out had a listing that I can't find now showing a clamping fixture to hold the center of the top down untill the urethane set up as the top reveal molding wouldn't hold it down. I think they had the same situation as I have.

Thanks,
Mark Smith

 

for some reason I am remembering that maybe the later C3 glass had more of a bend in it than the early cars did. Have you confirmed that they are using the correct glass? I am sure it can't be that easy and I am off on my memory. The glass should be even across the entire windshield frame. The the reveal molding is installed where it just almost touches the windshield. Most people have the problems where the glass in set back too deep and that is where the blocks can help.

here is the website I used to guide me in my install:

http://www.speakeasy.org/~pws/Corvette.htm


Sully

 

Sully, Yes they were the correct ones. Besides that I thought the difference was more in the black boarder as there was a difference in he dash pad position from 73 on up. Never heard about difference in curvature.

Mark

 

like I said before, maybe wishful imagination on my part. The black shading border makes more sense...

Sully

 

I remember someone saying that the 68-72 windshield lower edge is different, because of the wipers parking lower there, to clear the wiper door. I had mine changed two years ago, Pilkington, It fit okay. Lou.

 

Lou, Thanks for the reply, that is what I hear from some. Just talked to another local installer that just does classic cars and he says no two windshield frames are the same and weren't from the factory. However the new aftermarket glass he has found can vary in shape not only from brand to brand, but within each brand.

That is why my one question about gap at center on new aftermarket installs was asked. I need to see what has worked for others as far as gap at the center. I don't want to block a new window and have it break at install or a few months later.

Thanks,
Mark

 

Quite a few years ago I bought a Pilkington windshield at Carlisle for my 73. When I installed it a few months later the top right corner had a huge gap (1/2" or so) . With the help of some clamps and blocks I got it to fit.
I was hoping this is not common as I now need one for my 68.

 

just thought I would give some input here, I own a glass shop "Capital Auto Glass LLc " Raleigh NC. Just replaced windshield in 72 coupe, I am the one who pulled it into our bay and thought I must have a car like this so I bought one 6 weeks later - We had no issues with the install - we also used Pilkington glass part# Dw 714 GBN its the same glass for all vetts 68 thru 72. if you dont get a good fit when the urethane cures you may develop a stress crack. If ppg or plk glass did not fit I would think your frame would be the reason.

 

Put 2 Pilkington windshields in mine this spring (don't ask). Both went well. I also had the rusted frame corners replaced - no issues. I got the windshield from a place in Minnesota.

 

Thanks all, But as I said earlier. The original oem glass fit great and I made a template from a 70 that afriend owns and the frame looks correct. Many have said they had to block the glass to get good fit. For those folks, jut looking for how much of a gap you had to deal with. The link posted earlier will show how some have been doing it. http://www.speakeasy.org/~pws/Corvette.htm

Also one thing I didn't mention earlier that glass shops won't do the old style 3m windshield kits (shown in the above link) as they supposedly don't hold as well as urethane and because a windshield could pop out and not contribute its little bit to saving your life in a roll over.

Thanks,
Mark

 

Raphiki, Did you have to block it to get good trim fit?? You probably got it from auto city classics. They are just up the road from me and I have talked to their glass installer and he sees this fit issue very often as well.

Thanks,

Mark

 

It did come from Auto City Glass. Nice people! Gave me a good discount on the second windshield. I don't know exactly what you mean by blocking. They used the modern cement to install. The modern glass is thinner than the old stuff so they had to build it up a bit to get a good fit but they didn't seem to have a problem with it. When you order the windshield be sure to have them make sure it doesn't have the wide black stripes around the outside. That same DW 714 GBN comes both ways.

 

Hi Mark,
I too used a windshield made by Pilkington on my 71. (Auto City Classic too).
I installed it myself and was told over and over again that the glass MUST be installed dry so the exact position of the glass can be determined, and that all the ss trim can be installed and checked. It took a lot of work.
Only when you're satisfied with the fit of everything should the trim come back off, the windshield removed, the sealer applied, and the glass set.
This is double or triple the work, but makes for a nice looking job. The distance the glass is set off from the windshield frame is critical to how the glass and trim can fit.
Did your windshield installer trial fit the glass?
Regards,
Alan

 

Alan,

The the first one sat it in the frame and didn't install the trim. The new glass is so much thinner than the original he said there was no way to do a good dry fit. However I noticed that the glass didn't sit flush on the frame. He said the urethane would support it and hold it at the correct height which it didn't. It got worse overnight. Right side there was a gap of better than 1/2"between the glass and the side reveal molding.

The second installer sat the Pilkington in the frame and I could see the fit was better than the first ppg. He didn't feel comfortable with the fit and didn't want to tryto dry fit it any further in fear of breaking it due to the gap in the center.

This is why I have asked what gap if any in the center did others have. The pilkngton had about 3/8" when sitting dry in the frame. The installer thought that was too much and is in the process of getting a couple others from different production dates to see if he can get a better fit. I thought the 3/8" was not that bad. The first one (PPG)was almost 3/4" gap at the top of center with the top corners tight on the frame.

Thanks,
Mark

 

3/8" of a gap at top center is not that bad. the install will or should run a high v bead of urethane. don't use butyl tape because as stated it will not meet safety standards.

 

OL'SKEWL,
That is the kind of answer I was looking for... as in what gap at center during dry fit with nothing under the glass and top corners on the sealing area of the frame.

Don't want to turn this into a safety issue however if you used butyl on a vette vert I don't think it would make much of a difference as the additional strength the glass plus better adhesion would make much of a difference in a rollover. I know in my case if I got the old girl that much out of shape to roll as wide and low as she is I would have probably have died of being scared sh_____less long before my head hit the pavement.


Thanks,
Mark

 

understanding the roll over concern in a vert, but you still want the windshield to stay in the car in the event of a front end hit as well. you can literally take your feet and push out a windshield that has been installed using butyl tape. just make sure they use primer on the pinchweld to prevent any rust from developing.

 

I agree, and rust on these old cars is always there. Based on nothing really sticks that well to rust and you can never really get rid of rust. These are old cars and visual is what it is. Make it look good and drive it with saftey in mind. Saftey??? wasn't really a thing the auto companies were into in a real robust manner in the day. So for us to pursue that in later years is really in how we use the product.


Bottom line, please respond with your experience in regards to this topic... Gap at center during your aftermarket windshield install on dry fit...


Thanks,
Mark