The other thread re drybags got me looking more closely...
How can it be that the GG Uberlights are lighter (per the same volume) than the zpacks and the MLDs AND THEY HAVE eVent in the bottom??

7L GG = 15g (taped)
6L MLD = 18g (taped)
5.6L Zpacks = 18g (untaped/unsealed)

Is it a different thickness of CF?

Zpacks uses a thick Cuben for their dry bags. It's listed on their site. Joe also uses velcro for the enclosure that may add some grams. I've got one on order for my EE quilt that will be here next week. I like the Zpacks design the best.

From the Zpacks website: Constructed from black 1.0 oz/sqyd Cuben Fiber material. By comparison our regular stuff sacks are made from thinner .51 oz/sqyd (Cuben) material.

Don't forget you have to seam seal the Zpacks dry bags...

so yo are saying that Granitegear - which is a more wide spread mass market mfg, used such a thin CF that even with the eVent bottom its 7L is lighter than the smaller Zpacks and MLD?...what did they use..0.33osy? that seems extreme.

Re the zpacks - why do you like it the most? what use does the velcro have there?...if anything it creates some separation btw the sides and will let water creep in even after its folded...

makes it easier to get the top lined up before rolling. Doesn't add to or detract from the seal, which is created by the several rolls. Careful use makes velcro unnecessary. I have both MLD and zpacks drybags. All good.

Velcro - It's merely a matter of personal preference. If I break a buckle on a trip (and I have before), I'll still be able to close the bag, albeit in a slightly less waterproof fashion. I have a 5' tall 7 year old with very large feet who, on occasion, steps on things... And, I wanted the thicker Cuben bag for my quilt. Again, personal preference, not based on a scientific study.

Can't comment on the Cuben thickness of the other manufacturers.

I did some quick calculations based off the given dimensions of the bags. Since Zpacks is basically an envelope and GG uses more of a box shape, for fabric area I get:

GG
.33sqft @ standard .74oz/sqft cuben

Zpacks
.31sqft @ heavier 1.0oz/sqft cuben

So with some unit conversions and dimensional analysis we get an estimation of:

7.02 grams fabric for GG and 8.73 grams fabric for Zpacks. Take into account same buckle weight, thread weighs more than tape, and addition of velcro it's not hard for the 1.7g difference to grow to about 3grams.

That said we all just put in a lot of effort over 3 grams. For perspective if you forgot to take a penny out of your pocket on a hike, that's 2.5 grams of added weight...

IIRC the black CF can rub off. Anyone have a problem with the bags?

mld and zpacks switched to heavier cuben, cause some people had their 0.74 cuben sacks failing.

usually holes appeared or the fabric started to look like here

http://uloutdoors.wordpress.com/2011/09/25/pct-gear-reflections/


we are just talking about a few grams, so go for the heavier stuff imho

Joe's black cuben/nylon hybrid material rubs off a bit (due to the dyeing process). Black cuben (as used in Zpacks dry bags) does not have this problem.

GG makes cuben drybags that are all cuben, and then other ones that have the eVent bottoms. I've used the all cuben ones quite a bit. They'll hold up for a long time as long as you're not really cramming something in there (ie. a sleeping bag that barely fits). If you really cram stuff in then slowly the adhesive slips a bit and eventually a seam can come open. It happened to my wife.

The thicker variants of cuben aren't that much heavier and they're a lot more resistant to developing pin holes, so if you're really looking for a waterproof bag then get those. The lighter GG bags are good if you need a really light roll top bag that is going to be 95% waterproof but after a few months you won't really want to submerge it.

Lawson (LawsonEquipment.com) makes some awesome cuben dry bags too.

I just received a cuben fiber dry sack (and some other gear) from Lukes Ultralite, and it seems like a quality piece of kit. It also has bonded seams so no extra seam sealing required. Here is a link - http://lukesultralite.com/node/5

I've owned the Zpacks, GG, and Lawson's. Lawson's is the best I have used so far. Zpacks has some nice features, but seam sealing a dry bag is silly to me. Luke's design above is similar to Lawson's except with lighter cuben. I prefer the .18 stuff for reasons already stated.

Ryan

Does Lawson still make/sell the drybags? They're not on his website. I need some for an upcoming canyoneering trip.

Lawson is on hiatus selling cuben bags. May sell in the future though...

Hey Dan,

I just ordered a Rev X this morning and was curious what size stuff sack you went with for your quilt? Not sure if I actually read this in a thread or not, but I could've sworn that Tim said that the Medium-Plus size would work best.

Thanks!

Seam sealing a drybag? Not a drybag IMO, unless you happen to get every possible stitch hole w/sealant.

Lawson makes a stellar drybag, best cuben drybag IMO, and he definitely should add those to his regular stock.

+1 for Lawson's drybags. My wife and I got the largest one that we use as a pack liner on rafting trips. It fit perfectly in my Talon 44 and was really easy to use. Some drybags have a stiff piece of plastic along one side of the opening, I think to facilitate rolling the top down. Lawson's bags only have a strip of flexible nylon webbing, which I prefer because its actually easier to use. That stiff plastic stuff can get deformed and you're always working with a stiff curve.

All of the bags / dry bags I've gotten from MLD are pretty insane craftsmanship / glued seams, so no sealing necessary ......very nice. Have some Zpacks on the way as well so can't compare to those yet ...

I have had the MLD dry sacks and picked them because of the taping method. They are already mostly waterproof because of that, no seam sealing required. They will also hold water as is. When you roll them down you have to make sure you squeeze the air out first otherwise it has nowhere to go.

My friend has zpacks dry sacks and he has yet to seam seal them so the air just squeezes out of the seams. Once their sealed though I assume that won't happen.

Edited by pdcolelli42 on 02/24/2012 17:53:17 MST.

Andrew,

I'll give my opinion when my Zpacks Medium stuff sack arrives. It Depends on which quilt you went with, mine is an EE wide Reg, 40 deg. I think it can fit into a medium. I'll post my results and opinion next week.

Dan