Another 'How do they make that' question. (Curved Laminated Glass)

This is one product that I really puzzled about.
For flat laminated glass panels I can see how two sheets can be bonded/fused
to the inner plastic layer, but how one earth is single and dual curvature
laminated glass made.
Presumably the plastic interlayer would not stand the temperature needed to
form the glass, so both glass sheets must be moulded to slightly different
but incredible high tolerance so that there are no air pockets, which to me
seems unlikely.
I have Googled this topic several times over a few months, enquired in
person at the St Helens Glass Museum, and asked knowledgeable automotive
industry people, and not yet come up with an answer.
I know this is off topic regarding ME (unless one counts driving to the
local metal stockist in a car fitted with a curved laminated glass
windscreen!)
Ian Phillips
Reply to
Ian
Loading thread data ...
Air bubbles wouldn't be a problem if it's assembled under vacuum, and if the interlayer is soft enough to flow to accommodate curvature mismatch.
Reply to
Newshound
Don't know if your familar with the "How it's made" series on Discovery, but they showed the process of how they made car windscreens.....
Can't remember I'm afraid.
Michael
Reply to
Michael
Perhaps they form the 2 sheets together with an initial spacing sheet which is of the same thickness as the later bonding material?
Tom
Reply to
Tom
Interesting question.
Some good clues here:
formatting link
Pat Mackenzi
-- pmackenzi ----------------------------------------------------------------------- pmackenzie's Profile:
formatting link
this thread:
formatting link
Reply to
pmackenzie
I saw it too... a very interesting series if you like watching automated things!
As far as I can recall: Make float glass, cut into windscreen-like shape. These fit over a concave mould, and are heated until they sag into the right shape. In the tv show it was hard to see the mould - presumably very shiny - and almost looked as if the glass was sagging under it's own weight; but this must be the highly repeatable part. Then the formed glass is toughened.
To laminate, a glass-plastic-glass sandwich is rolled/pressed to remove air, then autoclaved. The plastic was poly-vinyl-whatsit and looked quite thin, like strong plastic bag thickness. Couldn't tell whether the two glass parts are from the same mould or not, unfortunately... I guess this depends on how tight the curvature gets. I noticed the crosshatch pattern in the laminate left by the rolling process is often visible in windscreens, especially at an angle.
btw, searching for 'how windshields are made' might give more detail.
hth Guy
Reply to
Guy Griffin
Pat
The mainland site is one I missed in my searches, it certainly explains the process well enough to satisfy my curiosity, thanks!
Ian
Reply to
Ian

Site Timeline

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.