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Discussion Starter · #1 ·
Has anyone but me noticed subtle ripples in his windshield? I'm not talking about the normal curvatures you see near a windshield's edges; this is a series of vertical "ridges" that seem to run all the way across.

You don't see these ripples when looking straight through the glass, but they become apparent at oblique angles. When driving, glance to the right (through the passenger side of the windshield) and watch how hard-edged objects warp as you go along. Imagine a ruler laid horizontally with a little "wave" or inchworm running left to right, and that's kind of what you'll see as you drive past a guardrail or any other straight, man-made object.

I thought this might have been a phenomenon restricted to the edges of the windshield, but the other day when my GTO was in the garage and the garage door was open, allowing in soft evening light, I was standing there and noticed that these little ripples appeared to run all the way across. It reminded me of the wings of a balsa wood airplane--paper stretched taut over spars, with each spar an inch or so apart.

Makes me wonder if my car had a windshield replacement before I took delivery. I just went out and looked at the label in the passenger-side corner: There's a diamond with some stylized initials in it, along with the word "laminated" and some other gobbledygook.

Oh well. It doesn't really matter anyway. I'm not going to get another windshield, and it's only a bother when I actually go looking for it.
 

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Haven't noticed any in my windshield, but I seem to notice a similar phenominon with my rear window. It may just be the defrost wires though, hasn't bothered me enough either.

I recently drove a brand new rental Chevy Trailblazer which in my opinion had an unacceptably wavy windshield, It was a vertical boundary a few inches in from the outboard edges of the windshield. I was surprised the quality team let this pass.
 

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Being a memeber of the SLP forum for a couple years until it died and then SS owner assoc. website, there was a small percentage of really flawed windshields in the 01 and 02 Fbods. Many got new ones under warranty as they were in their line of sight enough to bother them. If it's bad enough to bother you and is clearly visible to dealer you can probably get a new one.

my GTO glass is of good quality with no defects or distortion, except at bottom edge corners. :seeya:
 

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Discussion Starter · #5 ·
Think I'll Wait

I'm not unhappy enough about my windshield to do anything. If by some misfortune a rock wallops it one day, I guess I'll solve two problems in one fell swoop. My view and driving enjoyment aren't impacted, so I'm good.
 

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I was delighted to see the Pilkington logo on the glass in the GTO. They are the best supplier of plate glass in the world. Honda even specs them wherever they can. I don't think a lot of North American produced product has it.

Plate glass is made by a process called "float" where molten glass is dumped on top of a layer molten tin, of all things. The glass eventually lays flat over the tin -- and then goes through an eloborate process where different materials are sandwiched between different plates, etc. The technology is pretty amazing. I served as an advisor for a Pilkington spinoff that made contact lenses a few years ago -- and learned a little bit about their whole company in the process.

I think what MIGHT be going on, as I'm certainly no expert on this, is that either during the pouring or finishing process, such as during the sagging or molding of the curves, the glass may be subjected to some kind of harmonic vibration or variation in processing speed -- resulting in an uneven surface appearance. Kind of like what happens when you run timber through a blade to make casing -- if your speed isn't constant -- you get what looks like ripples running perpendicular to the finished product surface.

Anyway, if you want to learn about how automotive glass is made, go to:

http://www.pilkington.com/about+pil...d+processes/automotive+products+processes.htm

Man, my productivity has gone to crap since finding GTO Forum!
 

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I think that most likely it is a problem with the laminate process. Butacite could be thicker in those areas giving it a ripple effect.


FYI the tint srtip is actually in the Butacite, I found this out while walking through that building at the plant.
 

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Discussion Starter · #10 ·
THIS is why people like us join online forums. I am always stunned by the depth of arcane knowledge I tap into here. B A Better, you're scaring me! I think one day I'm going to submit a question about conjugating verbs in Portugese, just to see what happens.

Anyway, I clicked on B A Better's link to the Pilkington glass folks to see what their logo looked like, and to read a little about them. I immediately became doubtful that my car has Pilkington glass, as I haven't seen that "plus-sign" logo on my car.

So I just returned from the parking lot, and here's what I saw: On the windshield and rear window, there's a diamond-shaped logo with a stylized "FJ" inside it. The "F" is slightly higher than the "J," so that the cross member of the "F" goes straight into the top of the "J." At least, I think that's what I'm looking at. Could be a lowercase "rj," too.

Now, the rear quarter windows actually have the "PILKINGTON" name spelled out--but still no logo.

Any theories on what in tarnation all this means?
 

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B A BETTERPERSON is one of my favorite members on this site, he can pull things out of his ass and they are always correct! I to enjoy this site for information purposes, it's things like this that keep me coming back (and the biggest complaint I have with the "other" website who burn you when you ask anything)! :cheers
 

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Open mouth, insert foot. I saw the Pilkington trademark on the side glass and never thought of looking at the windshield and backlight because auto manufacturers usually negotiate master contracts for glass. If Sekurit gets the side glass -- they get the windshield, etc., too.

The FY is for Fuyao Glass Industry Group Co. -- a Chinese company. Makes sense as Australia is close to China. What a drag as I try not to buy Chinese made stuff whenever possible. That said, I would have bought the GTO anyway.

After thinking it over, those lines are probably flow lines from when the glass is molded. The only way you're ever going to get optically perfect glass is by taking a big chunk of it and grinding it down and polishing it. To make things cost effective -- a piece of hot glass is put into a mold and squeezed into shape. This happens during any molding process, like for PET plastic beverage bottles, etc., but nobody ever notices them because you don't have to look through them all the time!

Sorry for the bogus info. Geez, you DO learn a lot on these forums.
 
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