# eggcrate foam

**URL:** <https://boards.straightdope.com/t/eggcrate-foam/77911>\
**Category:** Factual Questions\
**Created:** [August 24, 2001, 2:41pm UTC](https://boards.straightdope.com/t/eggcrate-foam/77911 "2001-08-24T14:41:26Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![splinky](https://avatars.discourse-cdn.com/v4/letter/s/a9adbd/32.png) [@splinky](https://boards.straightdope.com/u/splinky)\
**Post date:** [August 24, 2001, 2:41pm UTC](https://boards.straightdope.com/t/eggcrate-foam/77911/1 "2001-08-24T14:41:26Z")

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How do they make eggcrate packing foam? I had always  
assumed it was molded into that shape, but I had the  
opportunity today to look at two interlocking pieces of  
such foam, and they obviously started life as a single  
piece of foam and were then cut in half in an eggcrate  
shape. But, try as I might, I can’t imagine a saw that  
could could accomplish such a task. Can anyone enlighten  
me?

Thanks in advance for any wisdom that is proffered.

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**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\
**Post date:** [August 24, 2001, 5:21pm UTC](https://boards.straightdope.com/t/eggcrate-foam/77911/2 "2001-08-24T17:21:52Z")

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Maybe they deform the foam, then just make a straight cut.

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**Author:** ![pluto](https://avatars.discourse-cdn.com/v4/letter/p/f08c70/32.png) [@pluto](https://boards.straightdope.com/u/pluto)\
**Post date:** [August 24, 2001, 6:07pm UTC](https://boards.straightdope.com/t/eggcrate-foam/77911/3 "2001-08-24T18:07:10Z")

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I don’t know the actual process used to manufacture said foam, but I wouldn’t abandon the molding hypothesis too quickly. Why couldn’t the mold be shaped so that the two pieces fit together snugly? In this day of computer-controlled machine tools it’s not hard to conceive of a milling machine capable of making such a mold.

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**Author:** ![demanton](https://avatars.discourse-cdn.com/v4/letter/d/3bc359/32.png) [@demanton](https://boards.straightdope.com/u/demanton)\
**Post date:** [August 24, 2001, 6:20pm UTC](https://boards.straightdope.com/t/eggcrate-foam/77911/4 "2001-08-24T18:20:47Z")

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According to the Polyurethane Foam Association, the foam is deformed and cut to produce the convoluted surface of egg crate foam. Read all about it [here](http://www.pfa.org/intouch/text/ntouch15.txt). Ain’t the internet grand? I’ll sleep easier on my egg crate mattress tonight, secure in my knowledge of it’s origin.

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**Author:** ![splinky](https://avatars.discourse-cdn.com/v4/letter/s/a9adbd/32.png) [@splinky](https://boards.straightdope.com/u/splinky)\
**Post date:** [August 24, 2001, 6:39pm UTC](https://boards.straightdope.com/t/eggcrate-foam/77911/5 "2001-08-24T18:39:49Z")

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Wow! I never would have thought of that. Very cool. Thanks to everyone who replied.