What's the hydro head on cuben ?

[Shewie]

I'm no expert, but I'm trying to figure out the relevance with regard to this material as a tarp. How much pressure are you looking at from a rain storm?

I think it was just something I picked up on while doing some research. HH is used to put a figure relating to waterproofness (if that's a word) by tent and tarp manufacturers. Trying to find out how cuben compares in those stakes makes sense if I'm going to shell out $300 on a winter tarp.

Cuben in a big downpour yesterday.........all dry underneath.
Shug

That's great news Shug, no sign of droplets or misting then ?

I really really want one so it's good to hear some feedback from those who've already purchased.

[PDA]

@Shewie: I used to sail with Mylar sails (not Cuben though) so have some experience. Also reading the test discussion from BPL it seems the concern was not new pristine material, which had a high HH of more than 3000, but that the mylar film was compromised by repeated folding, flapping and stuffing and that after a lot of simulated use, started weeping a little at as low as 422 mm. Certainly my sail was never overstressed, it was fully battened so it would never flog, and always carefully rolled as it came off the mast and never crumpled into lazy jacks; because I was warned by the sailmaker that creasing would sooner or later crack the film, and that overstressing would lead to sudden stretch and collapse of the film. The film used in Cuben is an order of magnitude thinner than the film used in my mainsail, so I assume that the same concerns exist. This doesn't mean that Cuben is not suitable for a tarp, but that it must be handled with care if it is to have a reasonable lifetime.

[SteelerNation]

Interesting. Out of convenience, I roll my CF tarp up to the ridge line before I slide on my net python skin. Sounds like I might accidentally be doing the right thing

SN

[Wags]

that thread is really the scary part of cuben. there's no real long term data on it. some part of that thread said something about cuben losing its waterproofness. i closed my eyes and pretended not to read that. some of those guys on that site are ridiculous with the scientific knowledge they bring to the table...

[Shug]

I think it was just something I picked up on while doing some research. HH is used to put a figure relating to waterproofness (if that's a word) by tent and tarp manufacturers. Trying to find out how cuben compares in those stakes makes sense if I'm going to shell out $300 on a winter tarp.



That's great news Shug, no sign of droplets or misting then ?

I really really want one so it's good to hear some feedback from those who've already purchased.

Hey Shewie....been pouring on and off all day and totally dry under the cuben. No condensation on the inside either. Cool weather day...51F or 11ºC
Shug

[PDA]

@steelernation: Your method sounds very like the way I (or my crew) rolled the sail as it came down the mast. Good practice. I suppose we should really do the same with our less exotic tarps too if we want them to last indefinitely.

[WV]

Steelernation, I also furl my tarp rolled up to the ridgeline. I used to use 5 bungee nacrabiners fastened tightly to secure it before sliding the snakeskin on. The nacrabiners trapped air in the tarp, so I developed a method of loosening them and milking the air out of the tarp to the ends. It packed up so small that I could handle it easily without the snakeskin, so I stopped using it. Then I started using a pack with a stretchy external mesh pocket (Aarn Mt. Magic 55), and discovered that the compression of the pocket still revealed bubbles of air trapped in the tarp. So, I reduced the number of nacrabiners to 3 and fastened them loosely instead of using multiple wraps to make them tight. Now simply putting the furled tarp in the mesh pocket compresses the air out the ends of the furled tarp, and it packs even smaller. I believe this handling of the tarp is still pretty gentle, and I haven't seen any degradation of its waterproofness. (Aside from this packing method, however, I haven't spared this tarp rough treatment, so I'm doubly glad it still holds water.)

That said, I saw the BPL article, pondered it at some length, and decided to get CTF3 with a slightly heavier layer of polyester laminate (CT1K.18 @ .8 oz/yd instead of CT.6K.08 @ .5 oz/yd). The new stuff looks wonderful (silver!). I look forward to comparing the long-term use of this material to the older tarp. I expect (hope )both will perform well.

[trunks]

Hmmm, I wonder how many "my cuben tarp's not waterproof anymore" threads there will be in 12 months time!

I think I might just bide my time for a while & see what transpires...

[Violent Green]

Hmmm, I wonder how many "my cuben tarp's not waterproof anymore" threads there will be in 12 months time!

I think I might just bide my time for a while & see what transpires...

Just for reference, some on BPL have been using cuben since 2005, so there is a lot of cuben out there. No leaky tarp reports that I have seen, although I admit I probably haven't seen every thread on the site in the last six years.

Ryan

[WV]

Just for reference, some on BPL have been using cuben since 2005, so there is a lot of cuben out there. No leaky tarp reports that I have seen, although I admit I probably haven't seen every thread on the site in the last six years.

Ryan

I agree. I read the entire thread on BPL, and didn't see any anecdotal confirmation of the tester's concerns, which I expected to see. With the proliferation of CTF3 tarps on the marketplace and especially in use by HF members, we should have more information to work with.