Cuben dry sack

[neilmny]

I've been searching for a "how to" for making a Cuben dry sack for a while without much success. Maybe Google was taking control of the situation
because I got lots of adds or reviews for ready made ones.

So I bit the bullet and made this one as a try out.
It has a 12mm wide "stiffener" on the opening made from a piece of a 2ltr milk container.
A 13mm buckle from Tiergear.
A piece of 13mm wide webbing also from Tiergear.
The adhesive is Venture tape 1163 from you guessed it.
25gm Cuben also from Simon.

I won't do a how to but happy to if someone would like the story.
A couple of notes - the bottom is double rolled with 1163 between each roll and the tops are roller 3 times with 3 1163 strips each side.
A small reinforcing tab was made to strengthen the "neck" cuts for each side of the "sealing" bits.
The buckles are in a sewn in loop of the webbing.

The finished product weighs 16 grams and is 420 high x 210 wide flattened out.
Total cost about $7.80.

I blew it up last night and rolled the seal 3 times and the photo if it inflated is from just now about midday the next day and there was no sign of deflation.....so I guess it is fully sealed.

Cuben dry flat.jpg (107.62 KiB) Viewed 6722 times

Cuben dry inflated.jpg (101.23 KiB) Viewed 6722 times

One more tip - if the glue on the 1163 gets in places it's not meant to be a tiny bit of talcum powder takes the sticky off it.

[Tortoise]

Excellent, Neil. Thanks a bunch for posting. I'll pick your brain when I get around to making mine.

I'll use the talcum powder tip on my booties project. I ended up with a sticky bit where i wasn't entirely accurate.

Cheers, and I'll look forward to reading about your next project.

[neilmny]

Thanks Tortoise and feel free to pick away.

[Orion]

Very nice job. It looks similar to the zpacks version.

I've been toying with the idea of making an inflatable pillow this way but have been worried about durability since Cuben is not very puncture resistant. I notice that zpacks uses the 35g weight for theirs, which of course makes it a bit heavier -- their 46x21cm bag weighs 25% more than your 42x21.

It would be interesting to hear from you sometime in the future as to how it has held up in use.

[neilmny]

Very nice job. It looks similar to the zpacks version.

I've been toying with the idea of making an inflatable pillow this way but have been worried about durability since Cuben is not very puncture resistant. I notice that zpacks uses the 35g weight for theirs, which of course makes it a bit heavier -- their 46x21cm bag weighs 25% more than your 42x21.

It would be interesting to hear from you sometime in the future as to how it has held up in use.

Thanks Orion.
I've never seen a Zpacks stuff sack but I suppose there's not really much you could vary in a bonded sack. The folds and seams need to be simple to handle as the adhesive tape is very agressive.
They might be using a different buckle, stiffener or webbing, which would influence the total difference
I only plan to store soft items or items that have no sharp bits in these bags, so abrasion will probably be the biggest enemy to longevity.

I followed the general method on this stuff sack video clip but with my own method for the top assembly.



I haven't as yet but will give some thought to constructing a block bottom bag.

[simonm]

Good job Neil.

The Zpacks dry bags use, or at least did, a small length of velcro around the top inner edge which acts as the stiffener. Their bags are also stitched and then taped.

I will be making a few dry bags and stuff sacks for my Overland walk at the end of this week, one to act as a pack liner.

[andrewa]

I've used my cuben dry bags as pillows and water containers ( around camp). They worked very well for both. My original ones were only glued together, but I've found that the ends of the "roll top" seem to want to unstick now, and I would therefore nowadays stitch them, and seal the seam to make it airtight.

A

[DanShell]

Great work, well done.

For those wondering how they last, I can say that mine have now done several trips and they are holding up fine.

My dry bags get stuffed and squashed quite forcefully and so no issues at all. I used a piece of hardish thin plastic strip as a stiffener for mine and it also looks like I used smaller clips....12mm I think.
I am converting all my bags to cuben. Even my tent, tent poles etc.

[neilmny]

They are probably the same buckle Dan, maybe 1/2" which could be nominally 12mm or 13mm as 1/2" is 12.7mm.
I'm thinking about a change over for all of mine too with maybe Tyvek bags for the bits and pieces that are a bit rougher to pack.

I made a sewn Tyvek stuff sack for my gas stove and pot kit.