Window Tinting Over Defrost Lines??

[Fitz98]

Not sure if this is where this post belongs, feel free to move it if there is a better place for it.
Went to get my 04 Nissan Sentra windows tinted. The tinter said that the old residue remaining on the rear window over and around the tint defrost lines will not likely come off without scraping off the defrost grid lines.
I live in Florida, so morning dew and humid days can sometimes fog up the rear glass. His recommendation was to use a ceramic coating on the outside of the rear glass to help compensate if we remove the grid lines.
He seemed to know what he was talking about, just not sure how I feel about having no defrost on the rear. Car will likely never see frost, so only humidity fogging is my only concern.
In Florida, I see white voids on window tint jobs all the time where these lines are, so I tend to believe what he is saying. We had this issue on our last tint job, which is why we need new tinting.
Opinions? Advice?

 

[JohnnyG]

He is correct.

 

[ctechbob]

Has the old tint already been removed? If not, how bad of shape is it in? If it is completely bubbled/purple, yea you're in for a rough time, if it is just faded, you can maybe steam it off and save the lines.

You're in FL, so if you want to attempt it, wait for a good hot sunny day. Get yourself a bottle of blue windex and a black trashbag big enough to cover the window.

Hose the window down with the windex (Inside the car where the tint is) and immediately apply the trash bag/plastic over the windex. If the windex dries out before you get it all to stay put, spray more behind the plastic (between the bag and the tint).

Now you wait for 20-30 min, check every 5 or so and spray more windex if it is drying out.

After about 20-30 min, carefully start peeling at one of the corners. It should start coming off in 1 sheet fairly easily. If it starts to not peel smoothly, stop, apply more windex and wait a little longer.

This is one of the best ways, if the tint isn't too far gone, to get a back window peeled with minimum scraping. Heat, moisture, and time are doing the work for you and releasing the glue and tint together.

Once you get the tint off, use the windex and a non-scratch plastic scrubber to work on any glue that's left behind.

 

[Dave9]

^ He's right.

If the installer doesn't have the patience or willingness to clean it off without destroying the grid lines, time to look for another installer.

 

[CorvairGeek]

WD-40 will dissolve the adhesive once the tint is off too. That is how I cleaned the defogger line on my Caprice and had it re-tinted. I always laughed at the no rear defogger cars on the lots in Florida in the 80s. I used it living there more than anywhere else.

 

[atikovi]

I live in Florida, so morning dew and humid days can sometimes fog up the rear glass.

Morning dew forms on the outside of the glass.
It gets pretty humid here in the summer too and I can't remember ever having the rear glass fog up.

If you're getting dew or fog on the inside of the glass, you probably have moisture on the inside of the car from a water leak.

 

[Fitz98]

I removed the old tint years ago and then it sat parked exposed to the sun with a sun shade inside only with occasional use.
The old tint was bubbled and purple and I used steam, heat, soap and water, plastic scrapers, you name it.
It came off in some places in sheets, in other spots it would tear while removing it.
I am going to remove the rear fabric deck and light and don't mind to spend more time to prep and clean, but the tinter said in his 10 years, when it is that old the adhesive does not always come off, especially right next to and over the conductive grid lines without scraping.

I can invest more time and elbow grease for prep, if spanning over the conductive grid is O.K.

He also mentioned it is probably best not to tint over the dotted matrix on the top part of that rear glass.
The last tint job looked bad there and it is almost impossible to get the glue off between these dots...obviously can't scrape that.

 

[ctechbob]

^ He's right.

If the installer doesn't have the patience or willingness to clean it off without destroying the grid lines, time to look for another installer.

Ehh, not necessarily. There are times when the tint is so old, so bubbled, and so hard that you just can't get it off any other way than scraping.

Trick is not to let it get that bad. 10 years in the GA/FL sun is about all the longer you want to go, even with a premium tint.

 

[ctechbob]

I removed the old tint years ago and then it sat parked exposed to the sun with a sun shade inside only with occasional use.
The old tint was bubbled and purple and I used steam, heat, soap and water, plastic scrapers, you name it.
It came off in some places in sheets, in other spots it would tear while removing it.
I am going to remove the rear fabric deck and light and don't mind to spend more time to prep and clean, but the tinter said in his 10 years, when it is that old the adhesive does not always come off, especially right next to and over the conductive grid lines without scraping.
View attachment 224568

I can invest more time and elbow grease for prep, if spanning over the conductive grid is O.K.

He also mentioned it is probably best not to tint over the dotted matrix on the top part of that rear glass.
The last tint job looked bad there and it is almost impossible to get the glue off between these dots...obviously can't scrape that.
View attachment 224569

Yea, the tint won't really adhere properly up there and usually looks wonky.

Not so bad when it is a thin strip around the outer edge, not great with big wide strips.

Some tint shops will use a vinyl material up there, but it won't match the rest of the tint and looks almost as bad as tint not sticking up there.

 

[Kira]

This has crossed my mind many times.
Why can't tint be applied in strips between the heater elements? I know there is a feathering of chemicals and that makes adhesion rates vary.
Yes, more is involved, but some regularity of measurement for strips would surface.
The retractable shade could make a comeback.

We had a '66 Oldsmobile with a defroster fan in the rear parcel shelf. It blew through a stamped metal grate.
I remember that feature working. It wasn't needed often.

 

[gfh77665]

Just had my 2017 Ford Fiesta re-done, original tint was applied in 2017. I was concerned about the strips so the tint guy told me he would steam off the old instead of scraping it off. No was harm done.

 

[Fitz98]

It wasn't needed often.

This was another consideration...we're handing it off to my son for his first car.
Does the few times he needs good visibility out of the back on a humid day with the AC on, warrant the trade off of a lasting, quality tint job.
Right now only 50% of the lines work anyways because the last tinter broke one side connection, but 50% got enough visibility eventually when needed.
I am of the mentality, it is there for a reason and if it is there, it should work (which would require me to fix the connection as well)

I guess the real question is if I could get all the glue off with time and effort, can I get a good tint job spanning the conductive raised lines on the inside.
I guess I will start with trying to clean the rear better and see if I can even get a good prep without removing the lines.

Anyone know how to fix this connection?

 

[ctechbob]

This has crossed my mind many times.
Why can't tint be applied in strips between the heater elements? I know there is a feathering of chemicals and that makes adhesion rates vary.
Yes, more is involved, but some regularity of measurement for strips would surface.

Yea, that tint job would look absolutely horrible. No way you could get that to look worth a crap, and no tinter on the planet would do it.

 

[atikovi]

I'm not sure what the fuss is about removing the tint over the grid lines. They are ceramic and bonded to the glass. As long as you scrape with the lines and not across them, it shouldn't be an issue. Used a razor blade on this Grand Am with no problems.

 

[CorvairGeek]

Morning dew forms on the outside of the glass.
It gets pretty humid here in the summer too and I can't remember ever having the rear glass fog up.

If you're getting dew or fog on the inside of the glass, you probably have moisture on the inside of the car from a water leak.

If a car sits out overnight, the windows will be covered with dew every morning for months in Florida. It evaporates off the outside with the heat from the defogger, just like frost.

 

[Skippy722]

Morning dew forms on the outside of the glass.
It gets pretty humid here in the summer too and I can't remember ever having the rear glass fog up.

If you're getting dew or fog on the inside of the glass, you probably have moisture on the inside of the car from a water leak.

Defrost still helps.. it’s one option I wish I had on my truck, a rear glass defroster.

 

[ctechbob]

I'm not sure what the fuss is about removing the tint over the grid lines. They are ceramic and bonded to the glass. As long as you scrape with the lines and not across them, it shouldn't be an issue. Used a razor blade on this Grand Am with no problems.

View attachment 224576

Uhh, no.

You scrape them with a razor blade and they're done. Yes the orange part in that picture is bonded to the glass, but the metal that carries the current is not and it will scrape right off. With the line, against the line, doesn't matter.

And yes, I've seen it hundreds of times. I used to work for a tint shop, and still hang out there whenever I want to stop in for a visit.

You can use a plastic scraper, but even then you don't want to just wail away on the lines.

 

[spasm3]

Anyone know how to fix this connection?
View attachment 224573

https://www.amazon.com/Permatex-213...234621&sprefix=defroster+epoxy,aps,137&sr=8-1

 

[Kira]

I worked at a dealership during the very dawn of 'heated element' defoggers.
Watching the 'older school' guys trying to apply the repair kits was painful.

Go the retractable shade route

 

[Fitz98]

Uhh, no.

You scrape them with a razor blade and they're done. Yes the orange part in that picture is bonded to the glass, but the metal that carries the current is not and it will scrape right off. With the line, against the line, doesn't matter.

And yes, I've seen it hundreds of times. I used to work for a tint shop, and still hang out there whenever I want to stop in for a visit.

You can use a plastic scraper, but even then you don't want to just wail away on the lines.

This is what the tinter was telling me.
He showed me a car where the orange lines stayed, but the current carrying lines were removed with a razor blade. Looked good, but no defrost option remained after that. He called the orange lines guide lines. I imagine their main purpose is to conceal the current carrying lines and adhesive from the outside. Maybe help with bonding the current carrying lines?
Other posts were correct about defrost option helping with dew on back window. Also same when running AC on a humid or rainy day. I guess this is the same as the heated mirrors I have on my Suburban. Without them it is sometimes impossible to see out of them on humid and rainy days or nights. The heated option helps. I want to try to keep it if possible.