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OT - Replacing a windshield,does the urethane need to be removed?

GregSY

Diamond
Joined
Jan 1, 2005
Location
Houston
Actually, not a front windshield but the rear glass in my 2016 Ram.

I removed the old glass, which was very well bonded in place by urethane adhesive.

I can use a razor knife to cut off the majority of the urethane left behind on the truck body. But a thin layer stays stuck to the truck, and getting it off will take a lot of effort and most likely damage the paint underneath and cause more damage than good.

I know these windows are replaced fairly quickly by 'pros'. I also doubt they are removing all of the urethane for the reasons above. My guess is they are leaving a thin layer and just letting the new urethane bond to it.

But, I'm not sure of that. Has anyone worked in a glass shop, or have better knowledge of this?
 
Has anyone worked in a glass shop, or have better knowledge of this?
Best friend does auto glass ... they just scrape it out the best they can, then put new goop down and drop the backglass in.

If it's rusted away underneath, that's when you have to get creative.

Used to use silicone a lot, but nowadays lots of times the glass is an integral part of the structure so have to use urethane for strength.

If you can do it by yourself in a modern car, you've got strong arms :)
 
I did a front windshield, once ages ago on a classic car, just got it as clean as I could with minimal effort. Never again, and now places like Safelite Auto Glass will come to you, and have reasonable prices. I don't see why people don't leave that job to the experts, I don't think the hassle is worth the savings.
 
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This is an age-old problem....'trust a professional' presumes a pro is doing it properly. Many pro's don't. It also requires me to go through life in an ignorant manner...I feel the world already has too many dumb people for me to volunteer becoming one.

Years back, we had 'Louie' lay some tile in the shop. Louie was a professional tile installer, and he owed us for some transmission work. We had already read the instruction on the QuikSet bag and discussed them prior to Louie's arrival. When Louie began work we noticed he was using a lot more water than the bag said, letting the QuikSet sit a lot longer than allowed, etc.

We asked Louie about it and he dismissed it with a wave of his hand, "Oh, that's not how I was taught".

Sure enough, a year later the tiles were coming loose. The professional, it seems, had been taught wrong. I am confident in the previous year he had laid dozens of jobs, also incorrectly.
 
This is an age-old problem....'trust a professional' presumes a pro is doing it properly. Many pro's don't. It also requires me to go through life in an ignorant manner...I feel the world already has too many dumb people for me to volunteer becoming one.

Years back, we had 'Louie' lay some tile in the shop. Louie was a professional tile installer, and he owed us for some transmission work. We had already read the instruction on the QuikSet bag and discussed them prior to Louie's arrival. When Louie began work we noticed he was using a lot more water than the bag said, letting the QuikSet sit a lot longer than allowed, etc.

We asked Louie about it and he dismissed it with a wave of his hand, "Oh, that's not how I was taught".

Sure enough, a year later the tiles were coming loose. The professional, it seems, had been taught wrong. I am confident in the previous year he had laid dozens of jobs, also incorrectly.

No argument from me! I just have had good luck with windshield installers after I did my first one and said, "screw this." Even though I won't travel behind a gravel truck for seconds more than I have to, I have gotten more than my share of cracked windshields. As with your experience I have gotten quite a few expert hack jobs. When I was younger it was due to being busy, as I get older I try to pick my battles. I have found the tradesmen most likely to be hacks are electricians, in my experience. Probably has to do with the fact most people don't want to mess with electricity, so they have a captive audience.
 
I have found the tradesmen most likely to be hacks are electricians, in my experience.

Haha, I agree. lucky for me i do all my elec work but a friend is a commercial electrician (he's ok) but some of the people he hires have no experience/knowledge and no brain to hand coordination
 
Haha, I agree. lucky for me i do all my elec work but a friend is a commercial electrician (he's ok) but some of the people he hires have no experience/knowledge and no brain to hand coordination

I do all my own electrical work also, the last one was pushing it. Had to replace the wiring to a well, getting a little old with a pair of bad knees to work in ditches and holes.
 
Just had the rear glass in my 2019 Grand Cherokee replaced by a glass shop. They came to me. Removed the interior trim. Disconnected the heater and wiper. Cut the adhesive with a wire. Straightened the bunged up wiper motor bracket. Cut off any way high goop spots with a razor blade and applied a ribbon of new goop. Set the glass. Redid everything and I was good to go. Swept up all the broken bits and said "That will be $330". No discount for reminding him he left his Apple phone on his van roof as he was driving away.
I did notice he used a power caulk gun, a new tube of goop and threw away the left over. The applicator he used also laid a ribbon that was pyramid shaped about 3/4" wide tapering to a point maybe 3/8" high. Made for a seal with no gaps.
BTW. A grand Cherokee will not fit in a 7' high garage door with the rear hatch open.....Bob
 
BTW. A grand Cherokee will not fit in a 7' high garage door with the rear hatch open.....Bob


Doh!

I almost did that with a 2 week old car, saved myself by less than a foot

I am with Greg, I do stuff because I want to know how. I am much more satisfied with a job done half assed that I didn't pay for [but did myself and learned something] than one done half assed by a pro.

'Usually' I am doing something over silly that I cannot get anyone to do
 
I knew a Master Electrician named "Cookie" for decades...he finally retired about 5 years ago. He worked for over 40 years as an electrician, eventually owned his own business.

The interesting thing about him is....Cookie couldn't read or write. No, he wasn't blind and he had both hands. He left school after failing out of 7th Grade. I asked his brother, "How can he be a Master Electrician if he can't read or write?"

It turns out he started working as an assistant for an older guy who was a Master Electrician. When the older guy took ill and passed away, Cookie just took over and used his license to sign off on jobs, etc. He operated that way for at least 25 years, maybe a bit more.
 
do not use silicone for auto glass. The acid will rust the window frame
Most cars don't last that long. When you're sticking a new windshield into an 86 Honda for a girl that's got twelve dollars and a pet turtle, it don't matter. Silicone is a lot more forgiving than urethane.

But as I said, normally these days they use urethane because the windshield is part of the structure.
 
There is youtubes on how to do it, seems like they leave a little bit and seal to the old urathane rather than scratching through the paint and causing rust getting it all off. I was going to do a front and rear window on a older ford ranger safelight was 900 dollars for the 2 windows so its going to be a while.
The other companys didnt have access to glass, tight market right now.
 
Actually, not a front windshield but the rear glass in my 2016 Ram.

I removed the old glass, which was very well bonded in place by urethane adhesive.

I can use a razor knife to cut off the majority of the urethane left behind on the truck body. But a thin layer stays stuck to the truck, and getting it off will take a lot of effort and most likely damage the paint underneath and cause more damage than good.

I know these windows are replaced fairly quickly by 'pros'. I also doubt they are removing all of the urethane for the reasons above. My guess is they are leaving a thin layer and just letting the new urethane bond to it.

But, I'm not sure of that. Has anyone worked in a glass shop, or have better knowledge of this?
I resealed the back glass on my truck. Pulled all the trim, unbolted the glass (my back glass has steel studs holding it in), cut all the adhesive with a flexible puddy knife, pulled it, then cleaned it with rubbing alcohol, then applied the new adhesive (some 3M stuff, don't recall the P/N.), bolted it back in and it's good as new (still no leaks about 5 years later). I did not strip the old sealant off.

Sent from my SAMSUNG-SM-G891A using Tapatalk
 
By the way, I was able to reuse the glass that was already there. A guy I know at a (large) glass company said they usually break them. I reckon that's what happens when you're in a hurry.

Sent from my SAMSUNG-SM-G891A using Tapatalk
 
I did watch several Youtube videos, painful as it was, and no one is removing all the old urethane. One on hand, that seems half-assed but on the other hand....I think my original assessment is probably correct in that it would do more damage than good.

For this truck, aftermarket glass is not produced for the rear glass....so OEM is the only choice.
 
I knew a Master Electrician named "Cookie" for decades...he finally retired about 5 years ago. He worked for over 40 years as an electrician, eventually owned his own business.

The interesting thing about him is....Cookie couldn't read or write. No, he wasn't blind and he had both hands. He left school after failing out of 7th Grade. I asked his brother, "How can he be a Master Electrician if he can't read or write?"

It turns out he started working as an assistant for an older guy who was a Master Electrician. When the older guy took ill and passed away, Cookie just took over and used his license to sign off on jobs, etc. He operated that way for at least 25 years, maybe a bit more.

I suppose as long as you can do math, and read numbers you can get by.
 
Still illegal...

But the way he got by was by hiring better educated electricians to do the work, then he would sign off on it using his credentials.
 








 
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