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An Ikea Bowl Has Been Setting Things on Fire

atlasobscura.com

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Re: An Ikea Bowl Has Been Setting Things on Fire

#101

Post by jefurii »

Freak_NL wrote: post #12

The same phenomenon occurs with glass spheres. If you think about it it is obvious enough (most people are familiar with how a magnifying glass concentrates the ray of the sun in a single spot), but it is something people tend to overlook when employing glass spheres as elements of your interior design — e.g., glass door knobs, large marbles, and decorative knick-knacks (which people have a tendency to place on their…

> The same phenomenon occurs with glass spheres.

Also clear water bottles (filled with water). In 1991 there was a brief period where homeowners all over Japan were putting clear PET bottles (PolyEthylene Terephthalate) at the edge of their properties because it was asserted on some talk show that the sparkles would keep animals away. This ended abruptly when a series of fires were started by the bottles.

Re: An Ikea Bowl Has Been Setting Things on Fire

#102

Post by cr0sh »

captainmuon wrote: post #64
vanderZwan wrote: post #51

Earlier quoted context omitted.

Well, melt the paint on cars. I suspect that the amount of energy required to melt an entire car would be quite a lot more than even a skyscraper worth of surface area could gather from the sun. > This isn't the first time Viñoly's architecture has raised eyebrows as well as temperatures: His Vdara Hotel in Las Vegas has been criticized for directing sunbeams onto the swimming pool deck that are hot enough to melt pl…

> I suspect that the amount of energy required to melt an entire car would be quite a lot more than even a skyscraper worth of surface area could gather from the sun. Actually, https://en.wikipedia.org/wiki/Solar_furnace ... The furnace in Odeillo, France can reach up to 3500 °C, and it's cross section is just about 50x50 meters. Of course, your typical skyscraper won't create those temperatures accidentially, but if…

Heck - if you purchase a new F-150, a simple engine fire can melt the entire thing to almost nothing (the truck is mostly made from aluminum - one of their prototypes a year or so ago on a test run caught fire to amusing results - no one was injured, fortunately)...

Re: An Ikea Bowl Has Been Setting Things on Fire

#103

Post by cr0sh »

corysama wrote: post #92
elliottcarlson wrote: post #65

Earlier quoted context omitted.

Where is the line between clickbait and attention grabbing headline. In the case of "You won't believe THIS simple trick to..." I'd definitely call it clickbait - but in this instance, the title reflects exactly what the article is about, and while the modified title on HN does a far better representation of the contents, I personally don't see the harm in how Atlas Obscura worded the title. Or maybe I am just really…

A major clickbait technique is to set up an "information gap". The headline almost tells you something interesting, but leaves out the most critical bit. This makes you feel uncomfortable because you almost had something but ended up deprived and are just one click away from closure. So, the difference between "An IKEA bowl" and "This IKEA bowl" is that "a bowl" is a complete idea. "This bowl" stresses that it's talk…

I was pretty certain I knew which bowl they were talking about before I clicked thru. While I didn't know the exact name of the bowl, I've been to Ikea enough to have an idea when I'm in the kitchenwares department.

Something I like to do when I'm out shopping is to look at products and figure out how to repurpose them into something else; I've often looked at this bowl and said to myself "That would be an almost perfect solar concentrator".

Usually, I'm looking to repurpose things for solar power usage or for robotics; Ikea actually has plenty of products to satisfy both.

Re: An Ikea Bowl Has Been Setting Things on Fire

#104

Post by cr0sh »

zhte415 wrote: post #75
jasonkostempski wrote: post #53

Earlier quoted context omitted.

I thought the title meant Ikea was disrupting the bowl industry.

IKEA disrupting the bowl industry. The global, quite conservative, retailer of everyday products has been disrupting the bowl industry for several decades. For years since disrupt was far from being the buzzword de jure, and was more associated with Klingon Battlecruisers.

I wish that Ikea would disrupt the automotive industry and start selling these:

http://oxgvt.com/the-ox-all-terrain-vehicle/

I would so love to build and own one - sadly, I don't think I'll ever be able to, because they likely won't be sold to regular consumers here in the US. Even as a flat-pack kit, I think regulators would figure out a way to keep them out of the market due to crash-testing compliance and/or pollution control/EPA issues.

So if I ever wanted to have something like one, I would have to homebrew it myself. I know it is possible to get such a vehicle legally registered, but it probably isn't super-easy, unless I start with a donor vehicle frame.

Re: An Ikea Bowl Has Been Setting Things on Fire

#105

Post by cr0sh »

sqeaky wrote: post #83
djmips wrote: post #77

Earlier quoted context omitted.

Yeah, like Mythbusters is definitive science. I'll half ass this with my high school level of education and TV budget and deadline and fail and declare it definitively busted!

No science is definitive. Even Isaac Newton was overturned. As near as I can tell they have put the most effort into duplicating Archimedes Heat Ray. They attempted it three times with large budgets and demonstrated why it was possible, but entirely impractical. After they showed that just being wet was enough to save the boat (when would a boat ever be wet?!) they then offered a replacement explanation and had an ex…

I haven't seen the episodes, but I wonder if in history (if it isn't just a made up legend) that a couple of actual events have become conflated due to lack of knowledge by the witnesses?

Perhaps there were a bunch of soldiers with mirrored shields, and they did shine their shields to "blind" the incoming ships. Then archers shot flaming arrows against the ships...

...and the legend of mirrored shields setting fire to a ship was born?

Re: An Ikea Bowl Has Been Setting Things on Fire

#106

Post by cr0sh »

masklinn wrote: post #17
jlebrech wrote: post #8

they can change the description to self lighting bbq and give it legs. It's also on my list of things to bring on a desert island.

You'd probably be better off with a magnifying or fresnel lens (or set of lenses), they're available as portable/survival tools (sometimes called "fire lenses" or "burning glass"). Fresnel are convenient as they're available in flexible flat rectangular plastic (e.g. credit-card sized). You lose in image quality so it's not great if you're trying to look at mosses or small critters, but to set stuff on fire it's real…

I carry three or four different means to set a fire in the backpack I carry when I go hiking; a credit-card sized fresnel lens is one of them.

I also like to scavenge the huge fresnel lens from larger (40+ inch) rear-projection TVs - these are often thrown out by people during our "bulk-trash pickup" days. It only takes a few minutes of work to remove the front screen of the TV (they are designed to be removed). A few more minutes will net you a huge silver first-surface mirror, too.

The fresnel lens from one of these TVs - mounted in a proper frame - can easily melt steel and rock. You have to be very careful when using it (wear proper clothing, plus welding goggles and gloves), and store it properly out of the sun afterward (because it can easily set things randomly on fire you don't want set on fire).

Re: An Ikea Bowl Has Been Setting Things on Fire

#108

Post by cr0sh »

agumonkey wrote: post #57

Smiling hard, I was looking for a solar concentrator online when I should have gone to the nearest IKEA store. ps: a video that go well with the PrimitiveTechnology channel

If you live in the US (or you know someone), and you have bulk-trash pickup (or can scavenge otherwise) - look around for an old 40 or 50 inch rear-projection television. All of them use a large fresnel lens for the screen (they also have an interest lenticular lens as well - but that isn't as useful due to it's short focal length). This lens, properly mounted, is capable of melting glass, rock, steel, etc. IE - if you use one as a solar concentrator, know what you are doing, as they can be very dangerous (not a toy). There are plenty of instructables and such online detailing how to build and use one - for instance:

http://www.instructables.com/id/Giant-Fresnel-Lens-Deathray-...

Re: An Ikea Bowl Has Been Setting Things on Fire

#109

Post by cr0sh »

DoubleMalt wrote: post #26

Reminds of this (sadly discontinued) project: http://www.photongrill.com/

Parabolic reflective solar cookers are fairly easy to build:

http://www.motherearthnews.com/diy/how-to-build-a-solar-cook...

If you do some research, you'll find a ton more examples. When I was around 11 years old, as part of a "science project" I built a small solar cooker to cook hotdogs with. I built a linear parabolic reflector (so that the focus was a line, instead of a spot), and placed the hotdog on this line using a skewer (a straightened piece of coathanger wire). It worked rather well.

The most efficient solar cookers, though, are solar ovens. As an adult, I've built ones using cardboard and tinfoil and cooked rice, beans, and made cornbread. You usually can't get them above 100 C (because of boiling and the vapor lowering the effective temperature inside), but if you can keep them properly oriented to the sun over hours, and keep the inner temp high enough, the oven can act as a very effective slow cooker for all kinds of food.

The trick with either one (concentrator or oven) is making them portable (easier with a concentrator - but it is possible to do it with an oven, too - if you change the design a bit). Check out some of the DIY plans out there; you'll be surprised at what is possible.

Re: An Ikea Bowl Has Been Setting Things on Fire

#110

Post by sqeaky »

cr0sh wrote: post #105
sqeaky wrote: post #83

Earlier quoted context omitted.

No science is definitive. Even Isaac Newton was overturned. As near as I can tell they have put the most effort into duplicating Archimedes Heat Ray. They attempted it three times with large budgets and demonstrated why it was possible, but entirely impractical. After they showed that just being wet was enough to save the boat (when would a boat ever be wet?!) they then offered a replacement explanation and had an ex…

I haven't seen the episodes, but I wonder if in history (if it isn't just a made up legend) that a couple of actual events have become conflated due to lack of knowledge by the witnesses? Perhaps there were a bunch of soldiers with mirrored shields, and they did shine their shields to "blind" the incoming ships. Then archers shot flaming arrows against the ships... ...and the legend of mirrored shields setting fire t…

This seems highly plausible to me. The polishing wouldn't even need to be intentional, just a bunch of people taking good care of their equipment could create the effect.
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