# World's largest pane of glass? **URL:** \ **Category:** Factual Questions\ **Created:** [July 21, 2009, 5:20pm UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752 "2009-07-21T17:20:11Z")\ **Posts on this page:** 18\ **Page:** 2
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [July 23, 2009, 6:44am UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752/21 "2009-07-23T06:44:14Z")
> [@Whack-a-Mole](#): > > I have seen a couple of cites stating that this ranch has the largest single pane of glass in North America. It measures 33’x10’. I think we’re back to optical telescopes as the largest, then. The largest is 10.4 meters diameter, and there are several of 10 meters. That’s quite a bit larger face area than these panes of glass. Even if we don’t consider that they are thicker, and much more complicated than a simple sheet of window glass, they are still larger. ---
**Author:** ![Whack-a-Mole](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/whack-a-mole/32/141_2.png) [@Whack-a-Mole](https://boards.straightdope.com/u/Whack-a-Mole)\ **Post date:** [July 23, 2009, 6:57am UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752/22 "2009-07-23T06:57:19Z")
> [@t-bonham@scc.net](#): > > I think we’re back to optical telescopes as the largest, then. > > The largest is 10.4 meters diameter, and there are several of 10 meters. That’s quite a bit larger face area than these panes of glass. Even if we don’t consider that they are thicker, and much more complicated than a simple sheet of window glass, they are still larger. Yeah. Guess the OP has to define a “pane” of glass. Just the biggest hunk-'o-glass there is or an actual pane? And for biggest are we talking surface area or weight? ---
**Author:** ![Whack-a-Mole](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/whack-a-mole/32/141_2.png) [@Whack-a-Mole](https://boards.straightdope.com/u/Whack-a-Mole)\ **Post date:** [July 23, 2009, 7:00am UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752/23 "2009-07-23T07:00:06Z")
> [@gotpasswords](#): > > And, you probably won’t catch me on the [world’s largest self-supporting glass staircase](http://plastics.dupont.com/myplastics/Mediator?common=5,4896,5549&locale=ch_CH). (As of 2006, at least) The ones at the Apple stores give me the willies as it is, but this one is much more open - [no risers, no bolts and much less hardware](http://plastics.dupont.com/plastics/en_US/images/highres/glseu0608ehi.jpg) to provide visual assurance that the thing isn’t about to collapse. I live in Chicago and the Apple staircase gives me the willies too. That seemingly unsupported one is downright disconcerting…cool but disconcerting. We must be weird though. I point out to my friends when we go to that store that the staircase is glass and they literally seem to not process that at all. It’s a staircase to them…who cares what it is made out of? Then I watch them blithely trot up the stairs and watch the stair flex under their weight and I cringe. The stairs are pretty damn cool though. ---
**Author:** ![bugme](https://avatars.discourse-cdn.com/v4/letter/b/bc79bd/32.png) [@bugme](https://boards.straightdope.com/u/bugme)\ **Post date:** [October 21, 2009, 7:05am UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752/24 "2009-10-21T07:05:24Z")
just dropped by because i was looking for the same thing wikipedia says that Monterey Bay Aquarium has the largest single paned window, the citation link mentions it under “How much water is in the Outer Bay Waters exhibit?” I would also be interested in seeing a list of these things, ---
**Author:** ![Francis\_Vaughan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/francis_vaughan/32/3093_2.png) [@Francis\_Vaughan](https://boards.straightdope.com/u/Francis_Vaughan)\ **Post date:** [October 21, 2009, 10:13am UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752/25 "2009-10-21T10:13:20Z")
I would be inclined to disqualify acrylic - it isn’t a glass. It is a cast resin. It is only glass in so far as it is a transparent sheet. There are a lot of single piece 8 metre diameter telescopes - they are spin cast by Roger Angel. This size is the technical limit of his process. The trick is that a spun liquid will form a parabaloid. So he fills a mould with glass pieces, starts it spinning around its axis, heats it up, lets the glass melt, form the right shape in the mould and then slowly (very slowly) cools it. Two advantages - the mirror’s surface is already close to the right shape, so a lot less work is needed. But more importantly - you don’t have huge changes to the internal stresses of the glass from removing all that extra glass. So making a single slab mirror that keeps its shape is possible. Bigger than this it gets pretty difficult. ---
**Author:** ![SuperStu](https://avatars.discourse-cdn.com/v4/letter/s/ee59a6/32.png) [@SuperStu](https://boards.straightdope.com/u/SuperStu)\ **Post date:** [June 12, 2011, 1:58pm UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752/26 "2011-06-12T13:58:22Z")
I work in the glass industry and the largest I have worked with is a panel of 15000mm x 4000mm x 25mm. This panel was a technical challenge to say the least and moving this from the factory in Northern China to the store where it was installed cost nearly $300,000 alone. I guess this qualifies as the largest. Stuart ---
**Author:** ![Disheavel](https://avatars.discourse-cdn.com/v4/letter/d/e274bd/32.png) [@Disheavel](https://boards.straightdope.com/u/Disheavel)\ **Post date:** [June 12, 2011, 4:03pm UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752/27 "2011-06-12T16:03:24Z")
Thanks SuperStu! 15m x 4m. Was the glass for use just as a window? or some specialized purpose? ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [June 13, 2011, 6:39am UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752/28 "2011-06-13T06:39:44Z")
glass zombies want … paaaaanes! Some people above cite 10 meter telescope mirrors. I believe all such are segmented, usually with 36 segments making up the entire mirror. AFAIK, the 8 meter mirrors that Francis Vaughan mentions are the largest single-piece telescope mirrors around. ---
**Author:** ![emathias](https://avatars.discourse-cdn.com/v4/letter/e/ee7513/32.png) [@emathias](https://boards.straightdope.com/u/emathias)\ **Post date:** [March 17, 2017, 2:08pm UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752/29 "2017-03-17T14:08:55Z")
> [@SuperStu](#): > > I work in the glass industry and the largest I have worked with is a panel of 15000mm x 4000mm x 25mm. This panel was a technical challenge to say the least and moving this from the factory in Northern China to the store where it was installed cost nearly $300,000 alone. > I guess this qualifies as the largest. > > Stuart These panes being installed in Chicago’s new Apple store being constructed on Michigan Avenue at the Chicago River look to be nearly that size: [![](https://i.imgur.com/9TZ2QV4.jpg) ](https://i.imgur.com/9TZ2QV4.jpg) ---
**Author:** ![boffking](https://avatars.discourse-cdn.com/v4/letter/b/858c86/32.png) [@boffking](https://boards.straightdope.com/u/boffking)\ **Post date:** [March 17, 2017, 4:09pm UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752/30 "2017-03-17T16:09:52Z")
I would look near volcanoes. Obsidian is a type of glass. What is the largest single piece of obsidian? ---
**Author:** ![DrCube](https://avatars.discourse-cdn.com/v4/letter/d/a3d4f5/32.png) [@DrCube](https://boards.straightdope.com/u/DrCube)\ **Post date:** [March 17, 2017, 4:47pm UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752/31 "2017-03-17T16:47:06Z")
> [@boffking](#): > > I would look near volcanoes. Obsidian is a type of glass. What is the largest single piece of obsidian? I would argue that a “pane” of glass is by definition man-made. ---
**Author:** ![RealityChuck](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/realitychuck/32/195_2.png) [@RealityChuck](https://boards.straightdope.com/u/RealityChuck)\ **Post date:** [March 17, 2017, 4:50pm UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752/32 "2017-03-17T16:50:07Z")
> [@astro](#): > > I think these glass store front panes are among the largest in the world > > The Sydney AU store claims to have the largest Watch out. That link brings up a fake virus warning. You’ll need to shut down your browser via task manager to quit it. ---
**Author:** ![Musicat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/musicat/32/20189_2.png) [@Musicat](https://boards.straightdope.com/u/Musicat)\ **Post date:** [March 17, 2017, 5:00pm UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752/33 "2017-03-17T17:00:52Z")
> [@RealityChuck](#): > > Watch out. That link brings up a fake virus warning. You’ll need to shut down your browser via task manager to quit it. Fake, probably. But I was able to close the tab in Chrome to exit it with no problems. ---
**Author:** ![Leaffan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leaffan/32/299_2.png) [@Leaffan](https://boards.straightdope.com/u/Leaffan)\ **Post date:** [March 17, 2017, 5:09pm UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752/34 "2017-03-17T17:09:00Z")
> [@emathias](#): > > These panes being installed in Chicago’s new Apple store being constructed on Michigan Avenue at the Chicago River look to be nearly that size: > > [Imgur: The magic of the Internet](http://i.imgur.com/9TZ2QV4.jpg) Careful. Blocked at work for potentially adult content. AKA pr0n. ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [March 17, 2017, 6:24pm UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752/35 "2017-03-17T18:24:22Z")
It is just a photograph. Your content blocking software is a moron. ---
**Author:** ![cmkeller](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cmkeller/32/118_2.png) [@cmkeller](https://boards.straightdope.com/u/cmkeller)\ **Post date:** [March 17, 2017, 7:15pm UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752/36 "2017-03-17T19:15:15Z")
garygnu: > [@](#): > > The Kansas City Royals are a very plain baseball team owned by Glass. A bit less plain in recent years. 🙂 ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [March 17, 2017, 7:20pm UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752/37 "2017-03-17T19:20:24Z")
> [@Francis\_Vaughan](#): > > I would be inclined to disqualify acrylic - it isn’t a glass. It is a cast resin. It is only glass in so far as it is a transparent sheet. > > There are a lot of single piece 8 metre diameter telescopes - they are spin cast by Roger Angel. This size is the technical limit of his process. The trick is that a spun liquid will form a parabaloid. So he fills a mould with glass pieces, starts it spinning around its axis, heats it up, lets the glass melt, form the right shape in the mould and then slowly (very slowly) cools it. Two advantages - the mirror’s surface is already close to the right shape, so a lot less work is needed. But more importantly - you don’t have huge changes to the internal stresses of the glass from removing all that extra glass. So making a single slab mirror that keeps its shape is possible. Bigger than this it gets pretty difficult. I know that this is a Zombie, but for anyone interested the [Steward Mirror Lab](http://mirrorlab.as.arizona.edu) gives tours, and you can see the mirrors in production. When I went there, they were polishing the dual-profile mirror for the [Large Synoptic Survey Telescope.](https://www.lsst.org) ---
**Author:** ![Evan\_Drake](https://avatars.discourse-cdn.com/v4/letter/e/b487fb/32.png) [@Evan\_Drake](https://boards.straightdope.com/u/Evan_Drake)\ **Post date:** [March 17, 2017, 9:33pm UTC](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752/38 "2017-03-17T21:33:22Z")
If the OP’s still around: > [@Tom\_Tildrum](#): > > Is this the sort of thing for which world records are kept? What/where is the largest single pane of glass? Pilkingtons invented modern float glass back in 1953. I’d guess if anyone keeps records of glass history it would be them. You could send an email. _Between 1953 and 1957, Sir Alastair Pilkington and Kenneth Bickerstaff of the UK’s Pilkington Brothers developed the first successful commercial application for forming a continuous ribbon of glass using a molten tin bath on which the molten glass flows unhindered under the influence of gravity. The success of this process lay in the careful balance of the volume of glass fed onto the bath, where it was flattened by its own weight. Full scale profitable sales of float glass were first achieved in 1960._ Wikipedia — **[Float Glass](https://en.wikipedia.org/wiki/Float_glass)** [Previous page](https://boards.straightdope.com/t/worlds-largest-pane-of-glass/503752.md?page=1)