Is butyl rope obsolete now?

[Mark1972]

Sorry for dragging up an older post, haven't been on for a while... This needs to be said.

Any of you guys installing your windshield with butyl tape are (God forbid) going to be in for a nasty surprise if you get in a serious accident. That stuff doesn't hold up and there is a reason why it isn't used anymore. Have a bad wreck and the last thing you want is a large piece of laminated glass flying around.

Have your windshields installed by professionals using urethane. That is it. Don't do anything else. A good glazier can run a damn near perfect bead of urethane that will look good and you don't have to smash the glass down into it so far that the trim doesn't fit well. It's easy to work with and, again, any good glazier can set it at the right height so your trim fits correctly.

I did auto glass for years. Cars would come in with that butyl tape crap and I could quite literally reach inside with my bare hand and push the entire windshield out - no tools required. That stuff has also, generally, been sitting on the shelf for years and it never seals worth a crap so you end up with leaks.

Urethane on the other hand has to be cut loose with a longknife razor. That's the only way your windshield will come loose. You could beat on it for hours with a hammer and chisel and you are NOT getting that windshield out except in pieces... So in an accident, you are protected. That is why they use it on modern cars, because it's the best way.

All the cars I've built have had new windshields done with urethane and they look perfect. It's too easy to do it the right way. You and your passengers deserve it.

I appreciate both sides to this, and have decided to use the urethane. I will be doing the work myself, and was wondering if you'd be able to give me a quick rundown of the steps to follow. The ledge where the window will sit has been primed and painted. The clips are in. The window has been dry fitted and seems good to install. I'm specifically curious about how much urethane to put on the ledge before laying in the glass. 1/8"? 3/16"? Once the window is in place and held to center by spacers, is more added to fill any "voids" and if so, before or after the original bead sets? I really appreciate any info.

 

[mopar 3 B]

Check the tube of any sealant. Most common cures are air, no air or moisture. Do not do anything that will affect sealant cure. That includes adding more of the same to fill a void.

 

[moparmarks]

Butyl acts different here in the dry heat than it does in the humid areas. I've removed a lot of 40 year old butyl glass that has spent it's life in the desert. Can be very hard to cut out with a cutting wire. Was in MO a few years ago and my friend pushed out a windshield by hand. Never had seen that before and doesn't happen on a car from around here. I had to remove a windshield that I installed about 6 year earlier with butyl and I almost broke it getting it out.

 

[69L48Z27]

I appreciate both sides to this, and have decided to use the urethane. I will be doing the work myself, and was wondering if you'd be able to give me a quick rundown of the steps to follow. The ledge where the window will sit has been primed and painted. The clips are in. The window has been dry fitted and seems good to install. I'm specifically curious about how much urethane to put on the ledge before laying in the glass. 1/8"? 3/16"? Once the window is in place and held to center by spacers, is more added to fill any "voids" and if so, before or after the original bead sets? I really appreciate any info.

Good call on the urethane, tape kits are no good. You can either shoot the pinch weld or the glass. Laying glass in with the bead on it may be a better way to go, you will need a second person and suctioncups to lay it in. Make sure you go straight in and don't roll the glass. You'll have a big mess.

I would recommend shooting a V-bead of urethane instead of a round bead. This will give the uerethane some height and it will not squish out as much. The older cars are not forgiving with room that the molding will hide. When you set the glass in don't smash it, gently press until you get the installed height your looking for. 3M uerethane you get at the parts store will cure in typically 24 hours.

You can smooth the back side of the glass with a popsicle stick type of tool. You shouldn't have any voids if you shoot a nice tall V-bead.

 

[Mark1972]

Mine pushed out by hand. South central Canada. Extreme heat and cold, and almost always higher humidity. It is a 1970, and had urethane sealant. I didnt see any evidence the window had ever been changed out before. I'll do more research before I install it.

 

[Mark1972]

Good call on the urethane, tape kits are no good. You can either shoot the pinch weld or the glass. Laying glass in with the bead on it may be a better way to go, you will need a second person and suctioncups to lay it in. Make sure you go straight in and don't roll the glass. You'll have a big mess.

I would recommend shooting a V-bead of urethane instead of a round bead. This will give the uerethane some height and it will not squish out as much. The older cars are not forgiving with room that the molding will hide. When you set the glass in don't smash it, gently press until you get the installed height your looking for. 3M uerethane you get at the parts store will cure in typically 24 hours.

You can smooth the back side of the glass with a popsicle stick type of tool. You shouldn't have any voids if you shoot a nice tall V-bead.

Thank you so much. I'll do my best.

 

[Nacho-RT74]

Sorry for dragging up an older post, haven't been on for a while... This needs to be said.

Any of you guys installing your windshield with butyl tape are (God forbid) going to be in for a nasty surprise if you get in a serious accident. That stuff doesn't hold up and there is a reason why it isn't used anymore. Have a bad wreck and the last thing you want is a large piece of laminated glass flying around

Well, actually original glasses are tempered not laminated

 

[72RoadrunnerGTX]

Well, actually original glasses are tempered not laminated

That is a factually incorrect statement, the factory never used tampered glass as a windshield on these cars.

 

[Nacho-RT74]

Well, I still have the factory tempered windshield of my car, which I replaced it due some schratches with another replacement windshield I found in better conditions than mine.

 

[72RoadrunnerGTX]

You have a mid-seventies Dodge Charger that came from the factory with a tempered glass windshield? Will need to back that up, post some pictures.
Again, all automotive manufactures used laminated (safety) glass for windshields for vehicles built for sale in the US, tempered glass for side and rear glass only.

 

[Nacho-RT74]

Yes! And I know in some moment the windshields were changes to laminated, but mine and all I have seen around ( factory and old replacements ) are tempered. My car was assembled in Venezuela.

I Have couple of windshields more also tempered.

I’m in Spain at this moment but could request some pics of the windshield

 

[flypaper]

Butyl acts different here in the dry heat than it does in the humid areas. I've removed a lot of 40 year old butyl glass that has spent it's life in the desert. Can be very hard to cut out with a cutting wire. Was in MO a few years ago and my friend pushed out a windshield by hand. Never had seen that before and doesn't happen on a car from around here. I

I have had to earn every front/rear glass
I have pulled around here
And I have done dozens of them.
I wish one of them pushed right out.

 

[kiwigtx]

Curious a s to Country of Manufacture here....
I know you guys spell some words funny, but WTF is this language from?

It had to be the most important word of that statement too.

 

[moparmarks]

I have never seen a tempered windshield here in the US. Side glass yes but not a windshield. Back in the late 70's someone broke the original windshield in my 54 Chevy truck and it was laminated. Every Mopar that I've owned 57-present had laminated windshields.

 

[moparmarks]

Well, I still have the factory tempered windshield of my car, which I replaced it due some schratches with another replacement windshield I found in better conditions than mine.

Would not meet US safety standards

 

[Nacho-RT74]

Maybe that’s the reason, being assembled locally. Can’t tell it but my car was assembled by Chrysler local plant, not a third party like Chrysler in Spain by Barreiros. True glass were also made locally

 

[69L48Z27]

I can't image a windshield break at 70 MPH with tempered glass. That would be a mess and then some. You would be blinded and bloody for sure. Wow.

 

[Mark1972]

Just a quick update. My friend and I installed my original rear window using the Proform window adhesive along with the Proform primer first. After dry fitting the window, fitting the spacers for an even fit, and applying the primer we were good to go. One 1/4" tall V bead of adhesive and lower the window gently. We then applied pressure from the centre of the window top and bottom starting in the middle and worked outward. Once we were happy there was no void at all we taped the window in place and waited an hour in a 75 degree garage. Removed the tape and the spacers and with the adhesive still tacky, applied a little more around the window into the pinch weld and spread it out smoothly with a gloved finger. Sorry I dont have a pick. But it turned out really well. I'm very happy. It sat for 2 more hours and then was driven 8 blocks home. The next day it was driven(damn this felt good)about 15 miles to it's new heated storage facility where it will be kept company by 200 others cars. Felt so good to drive the car for the first time. At 50mph with those 2.71 years it just floated along. Next year will be paint, new bumpers, and all the trim and weatherstripping. Cant wait. Thanks again for all the assistance with installing the window.

 

[Nacho-RT74]

I can't image a windshield break at 70 MPH with tempered glass. That would be a mess and then some. You would be blinded and bloody for sure. Wow.

actually tempered glass is less dangerous than laminated. The deal with laminated being safe is the layers between glasses but not the glass itself

The problem is the way how the tempered glass breaks all around in small pieces imposible to see through and that's the reason why is not used on windshields since long time ago.

 

[Dibbons]

Windshield, side glass, and bathroom shower material composition:
Tempered glass is one of two kinds of safety glass regularly used in applications in which standard glass could pose a potential danger. Tempered glass is four to five times stronger than standard glass and does not break into sharp shards when it fails. Tempered glass is manufactured through a process of extreme heating and rapid cooling, making it harder than normal glass.

The brittle nature of tempered glass causes it to shatter into small oval-shaped pebbles when broken. This eliminates the danger of sharp edges. Due to this property, along with its strength, tempered glass is often referred to as safety glass.

The thermal process that cures tempered glass also makes it heat resistant. Tempered glass is used to make the carafes in automatic coffee makers and the windows in ovens. Computer screens, skylights, door windows, tub enclosures and shower doors are more examples of places you will find tempered glass. Building codes also require the windows of many public structures to be made of tempered glass.

Automobiles use a different type of safety glass for the windshield and tempered glass for the back and side windows. Windshields are made from laminated glass, which sandwiches a sheet of plastic between two panels of glass. When the windshield breaks, the glass panels stick to the plastic film, rather than falling away to possibly injure the driver or other passengers.

https://www.yourmechanic.com/article/what-kind-of-glass-are-windshields-made-from