Replacing a front windshield

saudivette

Clueless In Sandland
Joined
Mar 24, 2008
Messages
2,633
Location
Aussie expat in Saudi Arabia
I finally got hold of a new front windshield. We're moving to a new compound in a few weeks so I won't be changing the screen yet but I want to oder the stuff I'll need.

Obviously I'll get a set of trim mouldings and screws but what about butyl tape or caulking tape? From what I've read, being an after market screen, it'll be thinner than OEM and if I use Urethane to hold the screen in, it'll sit in too far and there'll end up being a gap between the glass and the trim.

Suggestions...?
 
IMO, when doing a w/shield job....do the normal install, then around the CLEAN frame you need bed it all in with RTV black, I used REAL RTV from a caulking gun...and completely fill all the voids, totally and under compression from the stainless trim...that seals the trim down so that it would have to be cut out with a U knife....

what it does it stops rust cold,...on my '72 vert, I even went so far as to cover the top stainless with black vinyl, like a '70 A body vert I had....and so it has never leaked a drop over top seals....

OR down into the kick panels....and being a '72 with the wiper door, the fenders were filled with RTV black....and so it cost me about 20 bux to do that....

the car maybe have other faults, but it's NOT LEAKING from that windshield....

:hissyfit::hissyfit:
 
Do I put down the ribbon first then a bead of urethane over the top of that?

Gene, are you talking about RTV silicone?


Normally you don't use anything with it, once it touches it's stuck, but you could if you needed more height. Years ago with the thick glass 5/16 ribbon worked fine, so 3/8 should be right for thin.
In hot sunlight you can smash the up and down a little.

Most guys, put it on the glass, but like usual, I do it backwards, put it on the pinchweld and set the glass to it.
There should be some rubber bumpers in the kit to shim it from top to bottom.
Dry fit that first to adjust and trim them, then put the ribbon on the pinchweld leaving the paper on the windshield side. In the corners you will need to add wax paper or use the paper from the excess ribbon, where the paper probably split. Then lay in the windshield to test for up and down for the molding fit. You should have plenty of ribbon, so you can always cut off a couple little 2" pieces to test for moudings too. Then remove and use the prep solution the kit came with and set it in. I've done lots of them by myself, but I suggest you have a good helper that listens (that's the hard part) and dry fit it enough times to train them. Once the glass touches the ribbon, you are stuck. You will have to then learn how to cut out a windshield without damaging it if you screw up.

Test fit all your moulding clips etc before the windshield.
You can put it over primer, but I would paint the pinchweld area with good 2 part urethane finish paint first to better avoid rust problems down the road.

If you find it's a bit too high for the trim when done, put it out in the sun and gently push it down on the glass to fit the mouldings. New glass in really pretty flexible, but be gentle and spread your pressure with two hands.

You can seal the edge of the glass, ribbon and pinchweld with urethane, but don't fill the cavity, you need a place for water to run off. Cut down a plastic body squeegee. The new formulas for the 3m glass urethane is much better than silicone, have used both. Be carefull not to chip the edges anywhere, it can make a start for later cracks.

You can use just urethane caulk too, but that pretty well requires a hands on training course first. It can get ugly real fast.
 
I would not use RTV for that. Use Window Weld by 3M, it's black urethane. I would put it on the pillar and lay the glass on top.
 
Last edited:
Do I put down the ribbon first then a bead of urethane over the top of that?

Gene, are you talking about RTV silicone?


Normally you don't use anything with it, once it touches it's stuck, but you could if you needed more height. Years ago with the thick glass 5/16 ribbon worked fine, so 3/8 should be right for thin.
In hot sunlight you can smash the up and down a little.

Most guys, put it on the glass, but like usual, I do it backwards, put it on the pinchweld and set the glass to it.
There should be some rubber bumpers in the kit to shim it from top to bottom.
Dry fit that first to adjust and trim them, then put the ribbon on the pinchweld leaving the paper on the windshield side. In the corners you will need to add wax paper or use the paper from the excess ribbon, where the paper probably split. Then lay in the windshield to test for up and down for the molding fit. You should have plenty of ribbon, so you can always cut off a couple little 2" pieces to test for moudings too. Then remove and use the prep solution the kit came with and set it in. I've done lots of them by myself, but I suggest you have a good helper that listens (that's the hard part) and dry fit it enough times to train them. Once the glass touches the ribbon, you are stuck. You will have to then learn how to cut out a windshield without damaging it if you screw up.

Test fit all your moulding clips etc before the windshield.
You can put it over primer, but I would paint the pinchweld area with good 2 part urethane finish paint first to better avoid rust problems down the road.

If you find it's a bit too high for the trim when done, put it out in the sun and gently push it down on the glass to fit the mouldings. New glass in really pretty flexible, but be gentle and spread your pressure with two hands.

You can seal the edge of the glass, ribbon and pinchweld with urethane, but don't fill the cavity, you need a place for water to run off. Cut down a plastic body squeegee. The new formulas for the 3m glass urethane is much better than silicone, have used both. Be carefull not to chip the edges anywhere, it can make a start for later cracks.

You can use just urethane caulk too, but that pretty well requires a hands on training course first. It can get ugly real fast.

Good info, thanks. I'll be able to get the butyl tape and shimming blocks shipped here but no chemicals or solutions will make it here. I'm just trying to find a place now that stocks the butyl tape, shim blocks and all the various trim clips so I can order from one vendor...
 
You might be able to find this stuff over there at body shop supply wholesaler.

http://www.shop3m.com/3m-ribbon-sea...WINDSHIELD-ADHESIVES-AND-URETHANES-GC4J2DJJNQ

The priming fluid is just in a little soft plastic dispenser pouch. Probably less than a thimble full.
Haven't bought any for a few years so they might not even include it anymore.

Carbon tet is a good cleaner, but several wipes with acetone or laq thinner is good too. Just don't touch with your fingers after cleaning.
 
Saudi,

Since your not going to install the glass right away give me a few days to get a couple of pics up on what I would do. I is still your call ... but I would not go with the butyl ribbon ...(it will work) but that is old tech. I'll be back at the shop Tuesday and will make some photos.
 
I was trying to say that once the w/s was installed per NORMAL procedures as above.....then there is a gap ~3/8" all around there, and that is where water gets behind the trim...so I fill that with RTV, and bed/tape the trim down to it, making a 100% seal....course if you need remove the trim, out comes a U knife...

trapped water and wind and metal do not a winning combo make....

:smash::thumbs:

RTV is simple a GAP filler, and adhesive for the trim...that's ALL.....
 
This is what the installer used for my windshield:

100_1318.jpg

Test fit it dry with some spacer blocks so that the glass is not sitting too low. One important thing I should have done - mine sits just a little too low so there's a small gap between the trim and the glass that I filled with clear rtv.....
 
I bought some 3M butyl tape and I know I can get urethane locally if I need it. I also got all new clips for the mouldings etc.

Once we're all settled into our new place and I get back onto the BOSS, I'll pop the screen then leave it out until the interior's finished - well, at least until I've swapped the dash out.

Thanks for the input guys, no doubt there'll be more questions when I actually go to fit it...
 
I bought some 3M butyl tape and I know I can get urethane locally if I need it. I also got all new clips for the mouldings etc.

Once we're all settled into our new place and I get back onto the BOSS, I'll pop the screen then leave it out until the interior's finished - well, at least until I've swapped the dash out.

Thanks for the input guys, no doubt there'll be more questions when I actually go to fit it...

Don't waste your time with urethane if it will see sunlight. Urethane is not UV stable and degrades rather quickly when exposed.. that is why new car windshields have that black edge on them, it shields the urethane from the UV.

RTV silicone attacks butyl Have you ever seen a thermo pane window that is fogging inbetween the glass? Many times when replacing the window you will find the homeowner had set the glass with silicone so it wouldnt leak . The silicon off gases, attacking the butyl and then fogging begins.
 
Last edited:
I said Tuesday and now it's Thursday :clobbered: I had an interesting chat with
our glass man today (at our bodyshop the bulk of our glass work is done by an outside vendor)
and I learned something that before now I was not aware of.
In the U.S. federal law prohibits professional glass installers from installing ANY
auto glass with butyl ribbon that is not also bolted in.
A bolted in glass is typically
a quarter glass. This means if they are replacing a windshield it will be a urethane
installation regardless of how it may have been "originally" done.


Now the "Frit Band", that is the black strip you see on late model windshields.
This band does what the clip-on "moldings" did on the older cars. It protects
the bead from sunlight and gives the windshield a cosmetically clean looking
installation. The newer cars no longer have the clip-on moldings so this
is the main reason for the Frit Band so the installation would not look like
SH** (as my glass man put it) as apposed to a clear glass installation with
no moldings.

Your clip-on moldings will cover the bead .... but if you like you can simply add
your own Frit Band by tapeing off the back of the glass and adding one using
Black Pinchweld Primer.
http://www.technologylk.com/images/pdf/Spec-CRL950FC.pdf
Scroll down ... page 2 ... BLACK FRIT BAND

The pluses to Urethane vs. Butyl Ribbon.
1st and foremost is safety. (explains reason for Federal Law) The windshield
not only keeps wind out but is also to keep occupants IN...in the event of a
crash. An occupant not wearing their seat belt thrown into a glass held in by
butyl ribbon could easily find themselves and the windshield lying on the hood.

2nd with a proper urethane installation the glass is now a structural part of the
bird cage strengthening the car. Butyl ribbon can not offer this.
[ame=http://s127.photobucket.com/albums/p137/SMYDA/?action=view&current=a03.flv]th_a03.jpg[/ame]

Give me a couple more days and I put together a page on the do's and don'ts
and tips of a proper urethane installation with video and I'll post a link this tread.
It's been a heck of a week......:surrender:
 
I said Tuesday and now it's Thursday :clobbered: I had an interesting chat with
our glass man today (at our bodyshop the bulk of our glass work is done by an outside vendor)
and I learned something that before now I was not aware of.
In the U.S. federal law prohibits professional glass installers from installing ANY
auto glass with butyl ribbon that is not also bolted in.
A bolted in glass is typically
a quarter glass. This means if they are replacing a windshield it will be a urethane
installation regardless of how it may have been "originally" done.


Now the "Frit Band", that is the black strip you see on late model windshields.
This band does what the clip-on "moldings" did on the older cars. It protects
the bead from sunlight and gives the windshield a cosmetically clean looking
installation. The newer cars no longer have the clip-on moldings so this
is the main reason for the Frit Band so the installation would not look like
SH** (as my glass man put it) as apposed to a clear glass installation with
no moldings.

Your clip-on moldings will cover the bead .... but if you like you can simply add
your own Frit Band by tapeing off the back of the glass and adding one using
Black Pinchweld Primer.
http://www.technologylk.com/images/pdf/Spec-CRL950FC.pdf
Scroll down ... page 2 ... BLACK FRIT BAND

The pluses to Urethane vs. Butyl Ribbon.
1st and foremost is safety. (explains reason for Federal Law) The windshield
not only keeps wind out but is also to keep occupants IN...in the event of a
crash. An occupant not wearing their seat belt thrown into a glass held in by
butyl ribbon could easily find themselves and the windshield lying on the hood.

2nd with a proper urethane installation the glass is now a structural part of the
bird cage strengthening the car. Butyl ribbon can not offer this.
th_a03.jpg

Give me a couple more days and I put together a page on the do's and don'ts
and tips of a proper urethane installation with video and I'll post a link this tread.
It's been a heck of a week......:surrender:

Interesting knowledge ! I knew the urethane was required for proper operation of an SRS equipped vehicle .
I also was unaware that the black pinchweld primer would adhere to the glass sufficiently to provide a bond equal to the frit.
Upon reading the online manual there is a glass primer that needs to be used before the black primer.
Also on a rubber moulding installed windshield the info says that a polyurethane adhesive is to be used.


That is a question I have wondered about, how to convert a 65 mustang to a modern mounted windhshield.

Thanks for the info,, keep it coming!

CRL online tech manual: http://crlaurence.com.au/datasheets/pdfs/AGR_tech_man.pdf
 
Last edited:
That'a all just a bunch of government BS, more stupid laws to protect people from themselves by people that are trying to meet crash test specs. I believe that after a glass install the car is not to be driven for 24 hours too. All a bunch of nonsense.

I used to buy insurance wrecks for a living and out of hundreds and hundrds, have yet to see a butyl glass fall out, despite the head marks. Have even found pieces of scalp stuck to the headliners. Only ones I ever sew popped were the gasket mounted. If you're worried about a windshield keeping you inside a c3, then I doubt you will be around anyway.
Go to a junkyard and try cutting a butyl glass out, no fun even with the right tools.

Urethane is a much better glue though, follow the rules so you avoid the lawsuits. :lol:
 
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
 
Top