Dyneema Rope for pneumatic press

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kohto
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Dyneema Rope for pneumatic press

Post by kohto »

Is the use of dyneema rope for a pneumatic press viable?

For example if dyneema rope were to be substituted for the popular cordura fabric in most fabric presses, would the rope be able to withstand the pressure

I was thinking you could just wrap the rope around the press along its length and fasten it somehow
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Brazen
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Post by Brazen »

Yeah. What about dental floss? I was thinkin' maybe you could just somehow wrap that around the length and somehow fasten it. It's really strong and readily available.
"86% of the time it works 100% of the time".
skidesmond
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Post by skidesmond »

dyneema rope may stretch too much which will allow the press to flex/bend.
sammer
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Post by sammer »

Brazen wrote:Yeah. What about dental floss? I was thinkin' maybe you could just somehow wrap that around the length and somehow fasten it. It's really strong and readily available.
Why didn't I think of that?
My wife works at a dental clinic, that stuff's free!
I was gonna use old socks but dental floss is way stronger and smells better too. ummm minty
Thanks Brazen :D

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Damon
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Post by Damon »

Dyneema = Spectra. Both are UHMWPE fiber, just made by different companies.
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nate
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Post by nate »

skidesmond wrote:dyneema rope may stretch too much which will allow the press to flex/bend.
I don't know if OP is still considering this, but It's not all that bad of an idea. Dyneema doesn't stretch all that much, depending on how it's made. Or at least in the rock climbing community dyneema slings are known to stretch less that equivalent nylon slings. Sewn loops of dyneema sling are readily available for climbing use and are relatively cheap.
Bloefeld
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Dyneema Rope

Post by Bloefeld »

I am perplexed by what your problem is.

Dyneema and Spectra are both Gel Spun UHMW fibres mainly used in ballistic application.

They are the highest tensile strength per unit weight of all fibres at about 200,000 tensile. The elongation at break is around 2%. Creep is about 3%.

They are next to impossible to attach to something, knots will slip and the only way to adhere anything to them is to have them treated by Fluoro-Seal, Inc in Houston or from Honeywell treated in plasma.

I suspect you are looking at the tensile strength and hoping to make use of those properties.

I know that Burton has tried to use Spectra woven in a 2X twill treated for adhesion and found that the compressive properties did little to improve performance.

If you could perhaps give a better description of what you are trying to do, perhaps I can offer some more useful assistance
twizzstyle
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Re: Dyneema Rope

Post by twizzstyle »

Bloefeld wrote:I am perplexed by what your problem is.
Do a search for "fabric press" and you'll get an idea of what he's thinking about.
Bloefeld
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Re: Dyneema Rope

Post by Bloefeld »

twizzstyle wrote:
Bloefeld wrote:I am perplexed by what your problem is.
Do a search for "fabric press" and you'll get an idea of what he's thinking about.
Got it. Don't see the point of either. Seems a lot of trouble to build a frame that could be built in a few hours with steel.

Go to vacuum, easier and gets nearly perfect resin/fibre ratios if you leave the right bleeder/breathers.

Cheers,

Bloefeld
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nate
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Post by nate »

The reason for it is you can make the press for $100.
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chrismp
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Post by chrismp »

nate wrote:The reason for it is you can make the press for $100.
same goes for a cordura press and pressure distribution is easier with cordura bags.
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nate
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Post by nate »

chrismp wrote:
nate wrote:The reason for it is you can make the press for $100.
same goes for a cordura press and pressure distribution is easier with cordura bags.
Right, I meant fabric presses in general. My press is cordura as well, and I think that the cordura is in most ways preferable to the dyneema. The main advantage to dyneema is that you can buy a handful of already sewn loops at any climbing store. Whereas without a contact like MontuckyMadman I imagine it'd be harder to get small orders of cordura.
infinityskis
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Post by infinityskis »

would a duck cloth press work too??
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chrismp
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Post by chrismp »

either plywood or shopvac from this forum had a press frame made of duck cloth and if i recall correctly it ripped and they moved on to cordura.
infinityskis
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Post by infinityskis »

what pressure were they using?
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