David,

I'd be interested in the information for various kinds of silnylon myself. I think any style of cuben laminate would be more resistant to water penetration than just about any style of silnylon, though. The cuben products are basically two layers of strong polyester film with fibers squished in between. For water to penetrate the pressure would have to be great enough to break large numbers of fibers over a large area to rupture the unsupported film.

For water to penetrate silnylon, no fibers need to be broken. Silicone has a relatively low tensile strength, far lower than polyester film, and the thickness of the silicone coating is never uniform across a piece of silnylon. There are a handful of reports on these forums of misting through silnylon under a jet of water from a hose. The water goes between the nylon fibers, through small gaps in the silicone coating.

Numbers on hydrostatic head would be ideal. I hope my speculative rambling helps a little.

That makes sense. I've got 3 silnylon tents and I've been out in some pretty strong storms without the misting problem; I've had bouncing rain and condensation coating everything, but my DWR'ed down bags have never had a problem. I understand the hydrostatic head of most silnylon is around 1000mm, and so water will come through the material given the appropriate force. I think condensation management is a bigger issue.

I'm mulling over designs for a DIY cuben tarp and I'd rather end up with something at least as waterproof as the 1.1 sil I have right now. It makes sense to me that cuben should have a higher hydrostatic head.

I'm patterning out a double-wall UL tent right now, and am trying to determine the best [function: cost: weight] ratio. Basically, it seems like Cuben would be great for the floor for its waterproofness/weight (is .44 more waterproof then .3?). But since I can get, say, .75 oz sil at Kitebuilder for $10 give or take a few bucks, versus the $26 for Cuben (at Quest), would the sil do the trick for the rainfly? I mean, I'm talking about the difference between .44 and .75 ounce, for maybe 6 yards of fabric, difference of less than 2 ounces... Thanks for your input!

I don't think the weight difference is as big a deal as how the two fabrics 'handle'. Cuben doesn't stretch AT ALL, so your sewing and design needs to be perfect if you want a taught pitch. Silnylon, on the other hand, stretches a lot and so is more forgiving as a fly. Silnylon can seep if used as a floor (and possibly mist in really heavy cold rain) whereas cuben will remain waterproof as long as it doesn't get punctured. I don't know about 0.75 oz silnylon. I doubt that is the finished weight, so may be closer to 1 oz per yard after siliconization?

Allison, thanks. I want to make the thing all cuben, but I'm looking at $100 just for the floor, and the fly looks like it'll take about 50% more... I just remembered, I do have some silnylon that's been languishing around, same stuff equinox uses in their UL tarps... it's phenomenal stuff, really, but I have experienced minor misting in downpours.

The kinda ghetto reference is to "dyeing" cuben. If someone just wanted to tone down the glaring white, would it really be all that horrible to just mist over it with a can of spray paint?

I went to the trouble of doing all the "dyeing" experiments I described a little while ago in this thread because I found that spray paint didn't stick well to the cuben and it increased the weight of the cuben quite a bit. You wouldn't think a light coat would make much difference in the weight, but you'd be suprised. The dye is durable and it doesn't change the weight of the cuben(enough to measure).

Colin, thanks for doing all the experimentation and reporting you've done on this. I mentioned the paint dusting mostly tongue-in-cheek, but I am surprised that it increased the weight significantly. Off-handedly, it would seem that the aluminizing you did (which was very, very cool) would add at least as much weight as a dusting (not thick, barely mottling) shot of paint. I figured it would rub off pretty easily.

If it's not too late to revisit, the aluminized cuben has tons of potential. If I recall properly, you said that most of the cost was set-up. How much roughly for set-up costs, if you remember? (In part I'm thinking about Western M's Hotsac VBL, how they make that, other applications...)

Thanks!

I found that a small custom order of aluminized cuben for a tent or bivy would be between $1500 and $4000, depending on the method. 80% of that is "tooling", or set up cost.

Basically all of the aluminized fabrics and films (like space blankets, Hotsac bivys, window film, food packages, etc.)we usually see are made by thermal vapor deposition (which people in the industry tend to just call "metallization"). This method is fast and well suited to large volumes of product. That's how the aluminum was put on the sample pictured in my earlier post.

The other method available is sputtering. Sputtering produces a much more uniform metallic layer that has better adhesion to the film. You can get very durable, mirror-like surfaces with sputtering, but it costs twice as much as standard metallization, and the machines can only handle small pieces that would have to be joined later.

I think Graham mentioned that Cubic Tech has been working on some metallized products, but I haven't looked into it. I think it has potential, too. I was imagining a cuben pyramid tent that was half aluminized, so it could be pitched to give shade, or turned clear-side-east when it's chilly to catch the warm rays of the sun in the morning.

Hi,

Has anyone bought cuben directly from cubenfiberCorp recently? I will appreciate if anyone will post the email address for contacting the manufacturer.

Thanks
Huzefa

I just ordered and received my first bit of Cuben to play with, the .33oz from Quest. Even after reading everything I could online and preparing myself, I wasn't quite prepared for just how light the stuff really is!

BUT- I got the sample to play with before I buy yardage to make a tent. When I pulled across the width of the yardage, the fabric tore. I didn't exert all that much tension, perhaps as much as a tautly pitched tent at absolute most. I tried again, it tore again. When I looked more closely at the fabric, I found two seams going vertically on the yardage, about a foot or so in from each end. The tears were where the seams were.

Has anyone else had this problem? Is the .44oz constructed the same way? This piece will work for the small project I had in mind, but there's no way I'd trust it in a tent. Hopefully this was a random occurrence...

Hi,

Are you sure the Cuben was not doubled?

It comes that way sometimes and is really hard to tell.

Call Quest. Tell them what happened. If it is bad they will make it good for you.

If it was just doubled you may have gotten twice as much as you paid for.

Hi Bill,

My "sample" piece is about 6" x 48" or so. There's a seam about 12" in from each end--and a thicker line that could be one in the middle? Does the cuben sometimes get doubled in yardage width, or length? This was a remnant...

I appreciate your advice. That said, I probably won't bug Quest. They're good people, and I can still make this work for my project. Just wondering if this is common?

Hi,
I once bought a piece 18 yards long. When I unrolled it it measured 9 yard. I call Quest and Kat said to it must be doubled and to look on each long end for a way to open it. I did and found it was doubled. Cuben is so thin I had a hard time finding the right end.

This happened when they first starting selling Cuben. They check it now when they get it and if it is doubled they open it.

Did you buy the sample? If yes, I would say something to Kat about it. If it was cheap maybe that was why.

Hi, all-

Thought I'd post a couple pics of the torn cuben. I was going to buy a bunch of yardage to make a tent, but if it tears this easily, no way... Any others experience something like this?









You can see the diagonal stitches joining what are apparently 2 butted fabric ends. These stitches look to be what failed. As I said before, tears are about 12 inches in from each end of the 48 inch fabric width.

PS- I just wanted to say that Kay at Quest has been an outstanding person, tremendous resource, and providing great customer service--in all our conversations and transactions. I asked her about the cuben given my tent use concerns, and she wouldn't hear of not making up the torn fabric to me in some way. If you need any MYOG stuff, please give Quest a call.

Edited by 4quietwoods on 09/04/2008 15:31:06 MDT.

Sorry, Couldnt see a way to copy just the pic but i'm wondering if you had any further thoughts on your dye experiment Colin? The dye, the method, the results? Would you use the silicon edge again, do you think it would 'wick' far into the scrim? Have you tested for any weakening of the fabric? Did it have any remaining transparency after dye/pre aluminizing? Im keen to make a couple of large tarps though would like to do something about transparency if feasible?

Good on you for your efforts. I like your thinking ; )

Edited by bankse on 05/24/2011 10:50:17 MDT.

Paul,
You realize this thread is 3 years old, right?

And Colin just might not be following it anymore....

Hi Paul,

I just happened to see your post because it bumped this thread to the MYOG front page. I found dyeing cuben impractical. The dyes that will confer a color on the cuben require a swelling agent (a solvent) that weakens the film, and most of the colors come out subtle and translucent. When I used concentrated dyebaths to achieve a darker or more opaque color the finished cuben almost fell to pieces in my hands. I don't know a way to impart a color to the cuben, make it more opaque, or give it a matte (less shiny) surface without adding a lot of weight or weakening it. I think the colored products that Cubic Tech now offers are the best we can do, as far as I know.

...only on BPL.

What makes the space blankets so cheap? In light of talking about how aluminizing is so expensive.

Edited by rgmccoll on 05/24/2011 13:13:46 MDT.

The difference is quantity. Aluminized cuben is now available from Cubic Tech. They don't aluminize the cuben, they just use aluminized film to make the cuben. That film is essentially space blanket film, and it was aluminized on giant rolls, tens of thousands of square meters at a time, in a big vacuum chamber. That process probably costs several thousand dollars, but that comes out to pennies per square meter of space blanket. It would cost the same (several thousand dollars) to aluminize a dollar bill, because the cost comes from setting up the machine.