Went and looked at some SealLine bags today. The sealing mechanism wasn't terribly convincing. Probably I'm just not understanding something ... but thought I'd appeal to those in the know, with experience, on here.
(Will put bags in forward and aft storage compartments, so the stuff inside should be dry ... but ya never know.)
Roll closure bags can siphon water
through the seal, but usually only in small amounts. If your bulkhead compartment stays pretty dry, and you place the roll top seals so that they will not be submerged in stray water at the bottom, then you’ll be OK.
As a whitewater open canoe paddler, I have to expect gear bags to get sloshed, to sit in inches of water at times, and even to get submerged along with the boat. I have found that the roll top closures, once sloshed, and with some help due to temperature variations in the bag interior, will wick or siphon small amounts of water into the interior. For contents where it is vital to keep them dry, I use Watershed bags with their rubber closures similar to Ziplock; or I use Voyageur bags with slider closures. Neither will leak unless the bag is pierced. One can use roll top closures if one uses Ziplock or similar bags to protect contents from small amounts of leakage.
Most "dry bags"
use the same type of closing mechanism. Three rolls and clip. For really nice bags (a little pricey) look at WxTex bags. They have purge valves and can save a lot of room in your hatches.
I think I bought my last sealine bag when they had a lifetime guarantee. I think they don’t do that any more but the bags are very old and in great shape. I’ve gotten a few drips in the bags when they have been completely summerged in rough cold water. I highly recommend them.
If you're going on multi-day trips and think you'll pack your kayak to the limits then I'd say use Sea to Summit silnylon bags for your clothes and sleeping bag. They are as waterproof as any of the others and enable you to take more gear because the material they're made of makes them easy to pack and air is purged very easily.
The purge valve bags mentioned in the above post are very dry and do pack down well but I found they expand over the course of a day. They are more durable, but their design really ends up taking up much more space than any other bag I've used (because of their side seams) so the point of the purge valve is lost on me. I'm not sure if they are as durable as the Sealine bags because I've only used the bag I bought for one season.
I still have every Sealine bag I started out with 6 years ago and after many dozens of nights camping each year they are as good as new. They are very durable, very dry, but also take up more space than the Sea to Summit. If space is not an issue I use these first.
EDIT: If the sealing mechanism isn't convincing, buy the bag from a dealer who will allow you to return it, take it home and pack it with clothes then let it sit in the shower for a while. That will convince you.
Thanks for the input …
… I’ll probably try a Sealine (SealLine?) bag, the shop near here has quite a few in various sizes. My distrust of the seal is probably just ignorance.
No, as I said before, roll top closures
are neither airtight nor watertight. If closed carefully and packed carefully in the boat, they will do well enough, but they do not approach the watertight performance of Watershed or Voyageur. The posters above are only justifying what they have gotten away with. Probably you will get away with it too. Probably.
dry bags (urethane coated fabric with purge valve) are well made, durable, and dry. They pack down small using the purge valve (think squeezing the air out of a baloon). The side seams are 1/4 inch and just fold up out of the way when packing. I ordered from SP directly because I wanted the light grey color. WxTex bags are similar and can be found for sale online, in bright yellow and orange. Another brand allows you to "fill" the sealed bag with air using a stem on the purge valve, for use as flotation bags.
or ww kayaking it matters because there’s more of a chance that your bags will end up in the water. For sea kayaking trips it (hopefully) doesn’t matter.
I’ve tested every bag mentioned above and they were equally dry in the shower test. They all a very small amount of water in when submerged (by force in the bathtub) for longer than a few minutes. The Sea to Summit took the longest to let the water in.
Again, it depends
If you’re packing tight, whether for a long or a gear laden trip, the seam, the valve, and the roll top end up taking up alot of space. I kept mine in front of my footpegs the whole trip for that reason. It performed beautifully and kept everything dry although there was always plenty of water in the cockpit. But I’m not going to bring it with me next year.
Sea to Summit and Watershed
I’ll second Lyn’s comment on Sea to summit dry bags. I’ve used roll top closure bags from Seal Line, NRS, and Sea to Summit. I’ve punctured one NRS bag, but that could happen to any of the bags. They all work well, but as g2d said they are not designed to be submerged under water for significant periods of time. They all can wick some moisture. For my expensive electronic digital SLR I have a Watershed zip closure bag. It has a really incredible seal, but is bulkier than most roll tops. So, a mix of types works best for me.
I keep mine in my hatches, guess the huge purge valve doesn’t matter there.
these are great bags!
wx-tex dry bags
i have pretty much switched over to these exclusively....the purge valve works great and this saves a ton of room in kayak compartments...the material isn't as "sticky" as some of the sealine bags and this allows them to stuff into the boat much easier.
additionally, i like that if i need to use one as an impromptu float bag in case of repair, the valve gives me the option of inflating it in place and displacing water from a leaky compartment.
after 2 years, they've held up really well and everything that i've really needed to stay dry has stayed dry!
i have found them to be an excellent product!
Sea to summit
lined with a garbage bag. Light, non-bulky bags that are water tight as any roll top. Now, add a plastic bag liner, squeeze air out when compressing, roll plastic bag end and tuck down inside, roll dry bag top and seal.
Place said arrangement under water for as long as you want! It is a perfect combo.
I dislike heavy, rubbery cumbersome dry bags. Too hard to pack.
…some SealLines, Seattle Sports, WTX and some older vinyl things that I give away to people who show up with needing a drybag.
I have some SealLine Kodiaks and some Tapers. I hate the purge valve on them. Valve looks cool, nice and flat, ought to work but won’t for long. Also the coating that they use inside them is stickier than some others making packing a little more of a PIA. The outside material is good and slick, though.
I really like my small Seattle Sports Super Latitudes. the long side opening is nice. Easiest to load. They seal just fine. Purge valves are OK. Lower tech looking than SealLines but better function. My tent (minus poles) fits in one.
My favs are WTX. Feels a bit light and the purge valve sticks out but that valve works great. I can get much more air out without so much work. They are wonderful.
I recommend using many small bags rather than some large ones. Small gives you more packing efficiency and flexibility. Large ones will only fit in so many places making load balancing more challenging. I’ve got a bunch of Medium and large bags that are either new or barely used that I’ll sell you. I don’t use them.
Avoid those awful clear vinyl bags. Too sticky to pack. Or if you really want some come paddling with me and I’ll give you one.
WXTex bags are on sale at Campmor
for 1/2 price on the 15/25/65 L sizes. Have not seen a tapered bag from them though, so back to Seattle Sports if you want that or a mellow grey color versus the bright orange WXTex bags.
I will only suggest…
That for use in a kayak get the nylon ones vs the rubbery (PVC?) ones, as they are far easier to load and unload through the hatches and slide into place in a kayak. They last longer and don't crack the way the rubbery ones do either, and sand doesn't stick to them nearly as much as it does to the pvc ones.
Also buy many small/long bags vs big wide ones. Again, much easier to fit through the hatches and fit into the nooks and cranny's in a kayak.
The ones I have are SealLine and about ten years old. They have seen use at least three weeks a year and still look and work absolutely as new and have been nothing but a pleasure to use (unlike the rubbery ones).
I have never had any of them leak, but they have never really been put to a tough test in that regard. I find that the 'three roll and snap' closure is quite secure, especially if the bag is filled closer to capacity. They are more inclined to leak on a partially filled bag.
Think about how easy it is to open and close the bag ! This is very important when in camp, as you should always close the bag immediately after you get something out or put something in it.
Always close them up again as soon as possible to keep the humidity, dew and sand out of them !!! (!!!).
This makes a huge difference in how effected the contents are by the river environment.
Your stuff is a hundred times more likely to get damp from leaving the bag open over night than it is from the bag ending up in the river.
Great advice …
… thanks to all.