Are there any production cars with double curvature glass?

[Big time]

Being double curvature they can't (usually) be made by folding a flat glass.
Watching the cars from their sides you can see windshields and backlights are flat.

So are there any double curvature glass?
If so, how do they make the glass?

[Frank Lee]

Yes, one ancient example is the windshield on my '59 Chevy. Unfortunately a new "repro" windshield doesn't have the compound curvature and to me looks noticeably worse in profile.

Cad used same glass as Chevy; see the "fishbowl" (also note compound curved back glass):


Compound curve can be seen in reflection:


Replacement = flat


Basically, drape forming.

[botsapper]

Love the curved glass, front & back, and the lower/thinner proportions & old school swoop.
With a blasphemous new-school bagged suspension.

http://www.youtube.com/watch?v=WysFdc0brP4

[dremd]

Just ask window tinters, there are quite a few.
First to come to mind are mkiv VW "new" Beatle back glass.

[PaleMelanesian]

I was looking for this on the way home. MANY cars have compound curve glass.

Mitsubishi Eclipse (2002?)
Chevrolet Cobalt 2-door
Crown Victoria

Even my wife's Odyssey had a compound curve windshield. It even reverse-curves at the bottom, so the profile is a mild S shape.

[Blue Angel]

Originally Posted by Big time

Being double curvature they can't (usually) be made by folding a flat glass.
Watching the cars from their sides you can see windshields and backlights are flat.

So are there any double curvature glass?
If so, how do they make the glass?

I'm not aware of any production car today that actually uses flat or single curvature glass... maybe some industrial, agricultural vehicle applications, sure, but not production cars.

Tempered glass is made by heating the flat shape to soften it, lifting it onto a shaped mold (smaller lites by the edges, larger ones using forced air then pressing into a "hot ring" perimeter mold), then dropping into a perimeter support mold or "cold ring". Supported by its perimeter only, it is moved into the quench where high pressure air is blown over the hot glass to temper it.

Windshields are made by placing two sheets of thin glass together on a perimeter mold and heating the glass, allowing it to sag into the mold.

I worked as a Production Engineer at PPG's Oshawa Ontario glass plant before it was shut down. We made tempered back and side lites. I also spent some time in the Hawkesbury Ontario plant checking out their windshield process, quite different from tempered products.

Making glass with a single curvature (zero compound curvature) would require a completely different process, one that supported teh full shape of the glass somehow during quenching to keep gravity from adding any compound curve.

True, many windshields and back lites are very flat looking on modern cars, but are anything but in reality.

[aerohead]

Originally Posted by Big time

Being double curvature they can't (usually) be made by folding a flat glass.
Watching the cars from their sides you can see windshields and backlights are flat.

So are there any double curvature glass?
If so, how do they make the glass?

The ones you may be thinking of are from low-volume builders like Mosler,McLaren,'n such.
I've kept my eye on one from the Marauder Lola GT kit.They want $3,000 for one,but it is laminated safety glass and DOT certified.Aerodynamically,it's about as good as we are liable to find.
A company in California which does all-metal concept cars for Detroit can do these animals.They oven-heat the glass into Class-A tooling,which for the Lola is $29,000 for the mold.
A mold for the Bede PULSE/ Litestar is $10,000.

[Shepherd777]

Originally Posted by aerohead

A company in California which does all-metal concept cars for Detroit can do these animals.They oven-heat the glass into Class-A tooling,which for the Lola is $29,000 for the mold.
A mold for the Bede PULSE/ Litestar is $10,000.

Are you able to post a link to this firm?

[Shepherd777]

I have been thinking about using a Lexan windshield in the new truck. The "A" pillars are in the wrong location on this model. They need to be mounted more inboard. But this shows the windshield curvature.





This firm in Michigan coats Lexan for windshields: Welcome to Exatec - inspiring plastic glazing technology

They make the Lexan windshield and side windows for the new VW plug-in HEV: http://www.exatec.de/downloads/6553/...ch_4,_2013.pdf





I e-mailed them and even spoke with one of their salespersons in person at a trade show. They never got back to me. I cannot get a response from anyone with one-off requests. If you want to buy 10,000, they'll talk to you.

[Blue Angel]

Originally Posted by Blue Angel

Making glass with a single curvature (zero compound curvature) would require a completely different process, one that supported teh full shape of the glass somehow during quenching to keep gravity from adding any compound curve.

I apologize... I need to correct myself. We had a furnace in Oshawa that could make single curvature glass. It used a gradually changing set of rollers to shape the glass as it traveled along from the furnace into the quench. The rollers were actually oriented upwards in a curved manner as the glass traveled along, so the lites did have a slight complex curve to them, but a single curve lite could be made with this process.

I never worked on that line when I was there so it completely slipped my mind.