Replacing a front windshield

[saudivette]

Saudi,
man, i'm glad your asking all these questions, because i would have had to do the same in a month or so!
looks like your getting some good advice.
joe

I've had to jump through hoops to get hold of a windscreen so it's not just a matter of wanting to get it right first time, it's a matter of NEEDING to get it right. Like you said though, some good advice being put up :thumbs:

 

[SMYDA]

I believe that after a glass install the car is not to be driven for 24 hours too. All a bunch of nonsense.

Reason for this is that a number of cars equipped with passenger side airbags
use the windshield as a deflector/backboard. If a windshield were replaced and
a hour later the customer is involved in an accident triggering an airbag deployment
and the urethane is not cured the windshield could be blown out of the car.

Not very long ago I had a 4 door Jaguar in the shop that had the airbags deployed.
The "pressure alone" created inside the car blew the tops of all 4 doors out
far enough that you could stick your hand between the door frames and roof.

 

[68/70Vette]

Test fit all your moulding clips etc before the windshield.

The stainless steel trim pieces clip onto the little moulding clips riveted to the birdcage frame. They are steel and with age they rust. Removing the stainless steel mouldings, it's easy for one of these things to snap off. They are really cheap to buy so I'd suggest ordering some now so you'll have them if needed:i.e. won't have to delay finishing the windowshield replacement project until these parts come in. I remember seeing them for sale by one of the Corvette vendors, probably several vendors can sale them. Probably most body shops have a supply of them.

They are just pennies a piece I believe. Maybe some of the rusty ones, even if they don't break off, you might want to replace.

..............great discussion about the urethane and butyl adhesives.

 

[mrvette]

I believe that after a glass install the car is not to be driven for 24 hours too. All a bunch of nonsense.

Reason for this is that a number of cars equipped with passenger side airbags
use the windshield as a deflector/backboard. If a windshield were replaced and
a hour later the customer is involved in an accident triggering an airbag deployment
and the urethane is not cured the windshield could be blown out of the car.

Not very long ago I had a 4 door Jaguar in the shop that had the airbags deployed.
The "pressure alone" created inside the car blew the tops of all 4 doors out
far enough that you could stick your hand between the door frames and roof.

:surrender: Pardon ME, but...FUCK the God damned doors....and windows...but what about the total and complete loss of hearing???

talk about a BELL ringer>>

 

[saudivette]

Test fit all your moulding clips etc before the windshield.

The stainless steel trim pieces clip onto the little moulding clips riveted to the birdcage frame. They are steel and with age they rust. Removing the stainless steel mouldings, it's easy for one of these things to snap off. They are really cheap to buy so I'd suggest ordering some now so you'll have them if needed:i.e. won't have to delay finishing the windowshield replacement project until these parts come in. I remember seeing them for sale by one of the Corvette vendors, probably several vendors can sale them. Probably most body shops have a supply of them.

They are just pennies a piece I believe. Maybe some of the rusty ones, even if they don't break off, you might want to replace.

..............great discussion about the urethane and butyl adhesives.

One step ahead of you, I got all new clips coming

And you're right, they are are as cheap as chips :thumbs:

 

[SMYDA]

Sorry for taking so long to post this. I got the video uploaded to Photobucket and then dropped the ball. :clobbered: :tomato:
Got a little preoccupied with life ... :nuts: :rain:

I hope it is found helpful as I kinda tossed it together but I think the video
pretty much saids everything. If not I'll answer your questions as best I can.

http://www.vettemod.com/forum/showthread.php?t=5805

Also here is one on Rear defogger repair that may be found of interest.
http://www.vettemod.com/forum/showthread.php?t=5806

 

[saudivette]

Thank you John, that's absolutely fantastic :thumbs::thumbs::thumbs:

 

[SMYDA]

Old Post I know ..... but thought video was worth sharing.

 

[Arthur Brown]

great video, thanks for posting it

 

[turtlevette]

Old Post I know ..... but thought video was worth sharing.

http://www.youtube.com/watch?v=SLTtkS23S64&feature=player_embedded

Some seriously anal stuff going on there. But, that reminds me to check my airbags in my 75.

A windshield is NOT rollover protection. Perhaps that woman should have driven more "responsibly"

Alarm bells go off when i hear "nobody is doing it correctly"

This is the kind of thing that will lead to windshield installers refusing to replace a screen when the mounting surface has any rust or is othewise compromised in their opinion. Will they mount over POR15 which is basically sticking to rust? Should all old cars just be banned from public roads?

We have to backup and ask. What is the design intent of a windshield? Roof support for rollover? Occupant retension if they're not wearing belts? Airbag support in a collision?

If the design requires such stringent reqirements as no fingerprint oil, perfectly clean mounting surfaces. What is the definition of clean? How about mounting a screen in high humidity? Will the glue stick under humid conditions? How much glue is required?

A design that fussy is a poor design. Maybe steel chanels that screw to the frame need to be designed for positive retention? Maybe a high strengh alloy tube needs to be incorporated in the screen frame if rollover protection is really your intent? How about a structural beam right smack in the middle to support the roof like they do in NASCAR.

Should windshields be an inch thick and be made of very high strength polymers between layers of glass? A $5000 windshield?

We need to figure out a way to make this thing protect people who drive as carelessly as they please so they won't get a scratch.

 

[MYBAD79]

I believe one of the things the video clearly showed is that painter's latex is inferior to adhesive that designed to hold a windshield in place. That said, I checked the glue on my Mustang's windshield a few months ago and it can be peeled back easily, feels like the typical hardware store acryl.... :cussing:

when they installed my '79 windshield the installers used some nasty urethane glue tht seems to stick pretty good, I definitely feel good about this windshield staying in place - now, the 32 year old birdcage that it's attached to is another story......

 

[keywestjack]

Old Post I know ..... but thought video was worth sharing.

http://www.youtube.com/watch?v=SLTtkS23S64&feature=player_embedded

Some seriously anal stuff going on there. But, that reminds me to check my airbags in my 75.

A windshield is NOT rollover protection. Perhaps that woman should have driven more "responsibly"

Alarm bells go off when i hear "nobody is doing it correctly"

This is the kind of thing that will lead to windshield installers refusing to replace a screen when the mounting surface has any rust or is othewise compromised in their opinion. Will they mount over POR15 which is basically sticking to rust? Should all old cars just be banned from public roads?

We have to backup and ask. What is the design intent of a windshield? Roof support for rollover? Occupant retension if they're not wearing belts? Airbag support in a collision?

If the design requires such stringent reqirements as no fingerprint oil, perfectly clean mounting surfaces. What is the definition of clean? How about mounting a screen in high humidity? Will the glue stick under humid conditions? How much glue is required?

A design that fussy is a poor design. Maybe steel chanels that screw to the frame need to be designed for positive retention? Maybe a high strengh alloy tube needs to be incorporated in the screen frame if rollover protection is really your intent? How about a structural beam right smack in the middle to support the roof like they do in NASCAR.

Should windshields be an inch thick and be made of very high strength polymers between layers of glass? A $5000 windshield?

We need to figure out a way to make this thing protect people who drive as carelessly as they please so they won't get a scratch.

You make sense. Is the windshield in a C3 the same structural component as a windshield in a unibody car. For that reason I think a discussion of the pros and cons of different methods is like comparing apples to oranges.

 

[SMYDA]

Is the windshield in a C3 the same structural component as a windshield in a unibody car. For that reason I think a discussion of the pros and cons of different methods is like comparing apples to oranges.

We have Laminated Glass, Tempered Glass, Plate Glass, Wire Glass, etc ....
But basically Glass is Glass. 99.9% of all windshield are Laminated Glass (to my knowledge) that means 2 layers of glass with a laminate in the middle.
Door, rear, & side glass are usually always tempered glass... (the stuff that breaks into a billion pieces). The front windshield is made of a laminated and NOT temper due to the fact that a rock chip would cause it to explode in your face at speed. Lexus has a few models with laminate doors glass and Mercedes has a few with insulated door glass (like you'd find in a house).

Back to your comment ... the windshield in a unibody car is the same windshield (except for the shape) in a Corvette (laminated glass). So it does offer structure to the car if installed correctly for that purpose. Now were the engineers thinking this when they designed the C3 like they were when they designed the unibody ???????? Probably Not.

So to answer your question the glass is the same structural component as a windshield in a unibody car. But do keep in mind the rest of the car is inferior to a modern unibody.

 

[SMYDA]

If the design requires such stringent reqirements as no fingerprint oil, perfectly clean mounting surfaces. What is the definition of clean? How about mounting a screen in high humidity? Will the glue stick under humid conditions? How much glue is required?

I gonna get a little off topic but thought I'd throw it in anyhow .....
Urethane .... like in windshield urethane is moisture activated so the higher the humidity the quicker it will set up. You can actually water test a windshield with in minutes of installing it even though it may not be cured enough to make it safe to drive.

Urethane paints and primers are also moisture activated. Now don't go hose your car down with water while the paint is still wet :suicide:
But wetting a booth down to much and painting on a rainy day can cause your paint to cure to fast and make it difficult to buff.