Plastic on rig, question for riggers

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Just speaking from an engineering standpoint, there is no real reason why you couldn't make plastic hardware that would hold up. Probably would end up with UHMW HDPE or one of the more high performance plastic (amarids and so on), would be my guess.

Nobody would trust it, of course, as you can see in this thread. ;)

Plus, if you already have a supply of metal hardware (so no tooling or engineering costs) it would be a little pointless. There just isn't much reason to migrate to plastic, especially given the stigma it has.

What would the differential in manufacturing costs be? Any advantages plastics would have over alloys?

I wish Google Maps had an "Avoid Ghetto" routing option.

[sniper1rfa 0]

No idea. Probably not enough to bother with, especially considering plastic buckles for safety-critical applications would be a specialty item, rather than buying bulk webbing hardware.

I don't think plastics would have any real advantage. The hardware used in skydiving is already produced on a massive scale for any one of a million rigging applications, so it's not like we're hard up for quality hardware.

Plastic hardware would be re-inventing the wheel. ;)



EDIT: I'm reminded of a client I worked with once that wanted us to design a 3/4" drive ratchet extension for a tool kit he was producing; he was convinced he would be able to produce his own for cheaper than he would be able to buy them from an some well-established manufacturer. Boy was that a good one.

[Hvance 0]

That's what I was thinking.

I wish Google Maps had an "Avoid Ghetto" routing option.

[sniper1rfa 0]

Indeed.

Just figured I would throw it out there. Lots of plastic bashing going on, which is pretty amusing considering a skydiving rig is made almost entirely of plastic.

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..which is pretty amusing considering a skydiving rig is made almost entirely of plastic.

You think so? Nylon is related to plastic, but I'm not sure you could classify it as plastic, despite being petroleum based. And cordura?

I'm not an engineer though..

I wish Google Maps had an "Avoid Ghetto" routing option.

[sniper1rfa 0]

oh yeah, nylon (polyamide) is definitely plastic.

The problem is actually the term "plastic", which pretty much means "can be molded". Typically it refers to organic polymers, though "plasticity" is a material property that can be applied across all materials.

In fact, most of the materials used in parachutes are common plastics.

Nylon (polyamide) is obvious. Used for just about everything - the one that springs to mind that people have used are those white plastic screws. http://image.made-in-china.com/2f0j00uBvEGegqYibl/Plastic-Nylon-Screw.jpg

Dacron is PET (polyethylene terephthalate). Common use? Soda bottles. Common name? polyester. http://www.kjcf.net/images/index/products/petBottleZ.jpg

Spectra is UHMW polyethylene. Common use? plastic cutting boards. Its little sisters PE and HDPE are those whitish-clear tupperware containers. http://www.hospitalitywholesale.com.au/products/haccp-gastronorm-polyethylene-20mm-cutting-board1.jpg and http://feeds2.yourstorewizards.com/3363/images/250x1000/wi-pesc-4.jpg



Vectran is a type of polyester (not PET, but the group of plastics). I think it's related to kevlar, but i'm not certain on that.


EDIT: cordura appears to be a version of rayon, which from my reading seems to be more like some of the old-school plastics like cellulose acetate, which is what the famous old movie film is made from - the ones that are heinously flammable. :)

[sniper1rfa 0]

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EDIT: cordura appears to be a version of rayon, which from my reading seems to be more like some of the old-school plastics like cellulose acetate, which is what the famous old movie film is made from - the ones that are heinously flammable. :)

Just got corrected on this one - i didn't realize that cordura is a brand name, not a branded material (like lexan/polycarb or delrin/acetal). I guess the modern cordura fabrics are mostly polyester or nylon.

Reading more, cordura's original product was as I described above, but they've since changed it. No wonder I was confused. Reading along thinking "cellulose acetate? really?". That would be like saying "we make our products out of bakelite for durability!"

[bofh 0]

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EDIT: cordura appears to be a version of rayon

Cordura is a trade name that has been used for many different materials.
I believe the skydiving cordura is the "cordura classic" fiber which is made of nylon:
http://www.cordura.com/en/fabric/classic-fabric.html

[Hvance 0]

Interesting stuff. Thanks for the post.

I wish Google Maps had an "Avoid Ghetto" routing option.

[sniper1rfa 0]

You're welcome. :) . I think plastics are fascinating. The phrase "plastics make it possible" is not as sarcastic as people think. :P

Sadly, their usefulness is often misplaced. I hate seeing plastic wasted for no reason. The cutting board example above, for example, drives me nuts. Wood is better in just about every way. Save plastic (and most other petroleum products) for when there aren't other options.