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Comment by eyko | Hacker News Reader

A lot of their work is speculative (e.g. it's not clear that the layers of linen were glued, but they went with the assumption). It's interesting that they did not consider one of the most likely combinations: linen layers sewn onto leather. This would be more flexible (glue makes linen quite stiff) and more sweat resistant.

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It would also be relatively easy to puncture. Gluing the linen creates a composite material which should greatly outperform either of the component materials (the primitive animal glue will be almost crumbly on it's own, and woven cloth is very weak against punctures since there is very force holding parallel fibers of material close together). As is stated elsewhere, this is why things like fiberglass and carbon fiber are ubiquitous in the modern world.

Let me introduce you to the gambeson: https://en.wikipedia.org/wiki/Gambeson :)

Multiple layers of quilted cloth are extremely effective.

Im familiar, i think it works largely by being loose and giving. Arrows are fast, they have a lot of kinetic energy but relatively little momentum. You can decelerate them pretty effectively.

Thick layered cloth armor quite honestly also doesn't feel like something I'd bring if I was about go on a tour of conquest including such warm places as those conquered by Alexander the Great.

Having worn gambesons in the British summer during reenactment battles, I can't imagine wearing one in the Mediterranean sun let alone the Middle East. It gets extremely hot in there after even moderate physical exertion.

The glue is providing much of the structural strength. The fibers are providing tension to hold it together.

A similar approach has been used to make gears out of cloth. Stack cloth, cross-stitch, impregnate with resin, compress, cure, and then cut a gear out of the resulting block of material. It's one of those things people did before plastics. I have some old Teletypes with a few cloth gears, and you can see the woven pattern on the sides.

That is fascinating. I've not ever heard of that.

Can you share any more about that? Is there a particular name for it other than "cloth gears?"

I'm having a hard time Googling/DDGing it because "cloth gears" and every variation I can think of returns other things.

    It's one of those things people did before 
    plastics. I have some old Teletypes with a 
    few cloth gears, and you can see the woven 
    pattern on the sides

"Men and Volts", p. 317.[1]

Here's one you can buy, a replacement part for some old equipment.[2] Look at the large version of the picture. You can clearly see the stitching of the original cloth.

Composite materials, the early years. Composites are something long and thin with good tensile strength, combined with something strong but possibly brittle with good compressive strength. Probably the earliest composite was bricks with straw.

[1] https://archive.org/stream/menandvoltsstory00hammrich/menand...

[2] http://www.mcssl.com/store/4833177/fairbanks-morse-magneto-p...

Wow! That's fascinating. Thank you.

Search for "micarta gears". I'm not sure if that is a specific brand or a more general term but it results in lots of pictures. The gears are made of cloth and some sort of phenolic resin.

Seems the technique is also used by some for making knife handles out of cloth and epoxy resin.

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