If you can get by with a 40oz dirty bag these might work for replacement dirty bags. The material is simalar to a platy, and they appear well made. Pretty cheap too.

http://www.rumrunnerflasks.com/32oztravelerand8482.aspx

All of the prefilter talk reminded me I had some fabric biodiesel filter socks lying around from some previous water filter experiments. The fabric has 1 micron pores. You can find them at various biodiesel supply retailers.

I removed the rubber gasket from the dirty end of the sawyer squeeze filter, traced around it on the filter fabric and cut out a little circle of the filter fabric. I stuffed it into the dirty end of the filter, put the gasket back in (on top of it) and tried it out.

The Evernew bag didn't nest as far into the dirty end of the filter with the prefilter in place but I still had a tight seal with no leaks.

In squeeze mode, the setup worked fine; I couldn't notice any significant degradation in filtering speed.

In gravity mode, without any help along the way (e.g., squeezing), it took about twice as long (or even a little more) to filter 1 liter.

I found the (unaided) gravity performance to be unacceptably slow, but in squeeze mode, it might be a handy option for prefiltering turbid or questionable water.

I'm heading out on a 2-night trip in the a.m. so perhaps I'll bring along the prefilter and try it out some more.

IMO, it might be a preferable method to pre-filter the dirty water on the way IN to the dirty water bag instead.

If you use a make-shift cone or funnel, you can stretch your fine pre-filter mesh out over the funnel to pour the water thru, and then you have much more filter area to work with, and it should go faster that way. Even if it doesn't go faster, there could be an advantage to not having all that junk inside the bag.

I would prefer to do it that way, personally.

The flow rate from gravity is better than having to squeeze the bag. Both ways work but I like the easy gravity better.

That's exactly the same rig I set up in my shower! Worked fine for me, too. I hope to try it in the field soon!

On our next trip my wife and I will be camping a quarter mile away from the nearest drinking water so we will carry a one gallon dirty bottle to transport water. And, as usual, we will each carry 1 quart clean water bottles. These are "givens" and not included in weights below.

Here is my planned Sawyer application for that trip.*





WEIGHTS
One half of two liter pop bottle with string = 1 ounce
Coffee filter = 1/2 ounce
Sawyer Filter = about 3 ounces
Total = 4.5 ounces

PROTOCOL
When we want water we will simply pour water from dirty bottle into filter protected pop-bottle-half and let gravity fill our 1 quart clean water bottle.

I've tested everything out and the system seems to work fine.

*I've used ideas from most of the posters on this thread. Thanks.

Hey Jay: What bag is that (above)? I did the same thing years ago with a platypus (and different inline filter) and the bladder was fine. I assume that I can do that with most bladders, but it would be good to know (before I punched a hole in one).

A bit off topic, but I think it is interesting to see how much business Sawyer has created for itself with the squeeze bags. This sort of setup was possible for a long time, with various adapters. I used a platypus with a Seychelle filter for years. I never squeezed the bladder, but just sucked from the other end of the filter. I also added holes and cord (as mentioned) to create a drip filter. It all works well, but I do really like the Sawyer system, even though it has a few missing pieces (as folks have mentioned). One of things I really like is the pop-top and lid. This means I can keep the filter on the bladder if I have to carry the water. I can just put the whole thing in my pack and not worry about it leaking. I can then take it out and set it on the ground without worrying about it getting dirty.

I agree with the previous comment about the fact that Sawyer could make a bunch more money off this system. As it is, though, they are making plenty off of fairly poor bags (because their filter itself is so good). I wish they would give up on making water bottles and just sell adapters. At some point, I would guess that platypus (or someone else) will make an adapter anyway (although platypus sells its own filter, so maybe they won't).

Ross, That is 2L Evernew bag that has holes to punch out embedded in the plastic. You can visible see the potential holes to punch out. The Evernew bag fits the Sawyer Filter and the Platypus does not connect to the Sawyer Filter.

Edited by Creachen on 09/15/2012 21:33:16 MDT.

Harald,

Just returned from a 7 day backpacking trip using the filter just as you described in your 9/12/12 post with attached video. Everything worked great!

I didn't backflush during the trip and everything kept working just fine. I was doing about a gallon a day with clear water.

After getting home I checked the coffee screen pre-filter and it had collected some sediment so it is working and preventing at least some stuff from entering the filter.

Once home I backflushed with hot water from the kitchen faucet.

Thanks for the tips.

Daryl

Figured this might be a nice post to tuck into this thread of all things Sawyer Squeeze:

My Drying Technique

HTH

KJ

Edited by f8less on 09/25/2012 21:24:27 MDT.

Daryl, good to hear, my last 5 day trip I used most of that, except for the prefilter part, and had no issues, but the prefilter is something I think should extend the cleanout time, coffee filters like that are a few microns, no idea how many for that one. That was clean pacific northwest columbia gorge water, though some was from very small streams, like the one in the video, which I think you have to consider reasonably dirty in terms of suspended dirt particles in the water that are small.

My small syringe however I'm not certain about in terms of being a good idea, I have to check that, in the other sawyer thread going on someone posted an email from Sawyer noting that the first plunge should be strong to avoid forming channels in the mass of tubes, ie, clean in center, dirty on outside, not sure if the small syringe I found would create that much pressure, I'll take another look at it and see.

The large syringe with the tip that goes into the tube however would certainly improve the backflushing if you use a syringe. You might try that before backflushing with the sink, you get a lot more first oomph pressure on the first squeeze or two I think than a sink will provide. But maybe not, I don't know.

Edited by hhope on 09/26/2012 12:28:18 MDT.

Ken,

Interesting technique and info. Someone else posted awhile back that it takes a long time to dry any filter. Even with your sophisticated technique it takes a week. I would guess that most of us (if we don't use your technique) may never get our Sawyer filters dry between uses.

So with the Sawyer I think I'll use bleach on a regular basis to avoid as much internal "growth" as possible.

Question-After you get it really dry do you find it takes a bit of use to get things flowing again? Sawyer says it has to get well wetted to maximize flow.

Daryl

Daryl

I haven't had any flow issues other than it being slow for the first few seconds when you start squeezing water through it fully dry.

Another tip: You can also use the same air pump and tube to stick inside your water bags to dry them out in 1/4 the time.

HTH

KJ

I just set the bag+filter tilting down on a rock, water flowed into a pint bottle:



It takes a while to fill up the pint bottle, but I just fiddled around with other stuff.

Also note the 1 liter soda (PET) bottle with top cut off - 0.6 ounce. I use it to scoop untreated water into Sawyer bag. Marks at 1 cup, 1 pint, and 1/2 liter level. Then I can measure the right amount of untreated water for soup/oatmeal/coffee/tea.

I didn't pre-filter the water. The water was pretty clean. I probably could have drunk it untreated. Except for one day I noticed a salamander swimming around in the pool where I took my water from.

Jerry,

That's about as simple as it can get.

Daryl

During colder weather I may be sleeping with my filter. I don't want it to drip water onto my bag. Here's my current set-up for avoiding a damp bag. Haven't tried it yet but it looks like it should work.





White adjustable cap came with filter (barely shows up in first photo due to white table). Grey end cap was purchased separately. I put a small vynal end cap on the grey cap to prevent water from coming through the hole. Total weight of the caps is about 10 grams on my scale.

Edited by lyrad1 on 10/11/2012 08:44:11 MDT.

Just use a pint zip loc bag. Plus, it adds a little insulation to keep it from freezing.

Jerry,

I haven't had real good luck with zip top bags. Over time the zippers open up and/or fail to seal properly when zipping them shut.

Sounds like your experience has been different. Any tips? Do you use the regular ones or the freezer ones?

Daryl

"Someone else posted awhile back that it takes a long time to dry any filter".

That may have been me. I cut two different filter cartridges in half with a band saw for inspection...a Katadyn Hiker and MSR Sweetwater. It had been 3 yrs since the latter was used. I don't recall any moisture in it. However, there WAS moisture inside the Katatdyn Hiker cartridge after more than a year of not using.

Freezer bags are sturdier, but heavier. Regardless, you have to replace occasionally.

If you shake out the Squeeze vigorously - hold at arm's length and swing as fast as possible, multiple times, then there is very little free water left so the zipper seal doesn't really have to hold back very much water.

If you fill a zip bag with water and hold upside down, yeah it will leak