Sawyer Mini rocks!

I re read this thread.. again..

http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=78861

I understand the concerns and it's fair to say that using the Smartwater bottle to back flush is not a once size fits all solution. Where I hike, most of the water I drink doesn't need to be filtered in the first place but I do as an extra margin of safety. It's very clear with no visible algae.

For what I do, I can back flush the filter in the field with the Smartbottle and then hit it with the syringe before I store it after the hike. If I'm wrong, I suspect the worst I'll see is a slower flow rate. Even if the filter completely failed, I carry purification tablets for that contingency. If this was a $200 filter I'd probably be more anal but at $25…. meh!

Newbie question here; I have been eyeballing the Sawyer mini for awhile and due to this thread I ordered one from Traildesigns.com. Are all the bags compatible with this newer smaller filter because I'd like to order some additional larger bags than the 16oz one that came with the filter but didn't want to pull the trigger until I knew for sure that they'd work with it. Thanks!

Yep they are. So are the evernew bags as well as any standard soda/water bottle. I screwed my mini into an Aquafina bottle I had in the kitchen and it was a perfect fit. This new filter is sweet!

Great! Any usage tips. After my MSR miniworks failing in Glacier I am kinda miffed at that thing right now and am excited to use the Sawyer.

a certain vintage of Platypus bags presumably won't work – thread pitch is a little different – since it's plastic it bends so it sort of works but water leaks around threads

lots of threads about usage – make sure and backflush before and after every trip. I think soda or water bottle works better because you can put more pressure on it.

I've been having problems with the original Sawyer's gasket. I really like using a PET bottle but I found that the gasket was becoming lodged in the neck of the bottle every time I used it. I switched to the Sawyer bags and the problem persisted. The gasket started deteriorating where dirty water was running into the clean and I eventually had to replace it. This was after using it less than 20 or 30 liters.

My next/current Sawyer had the same problem almost immediately. I compared how my gasket is seated in there compared to an unused one and I see no difference. I started having this problem when I used it with a PET bottle. I received a response from Sawyer; they said that this was due to me over tightening it. I didn't think I was but I'll go with it. I think the vacuum created using a PET bottle may be a contributing factor. I'll upload pictures later.

I looked at Lowes for a new gasket but couldn't find one. I ended up making a few spares to keep in my ditty bag; they're ugly as he!! but they seem to work. Sawyer is mailing me a new one.

From a customer service standpoint, they are bi polar. They were more than happy to send me a new gasket but historically their stance on failing bags or other issues is that it's the user's fault and there isn't a problem with their product. I agree that in general, UL equipment needs to be handled with care but it seems that the problem with the old bags wasn't user error across the board. For the record, I've only used the newer bags and haven't had a problem with them.

Seems like I'm the only one who's having a problem with the gasket so I'm more willing to take the blame for that.

Even with these issues, I still like it enough that I bought the mini. For $25 it's a small gamble.

I may return to the Steripen but the Sawyer is my go-to system for the time being.

I always carry iodine or chlorine dioxide regardless if I'm using the Steripen or Sawyer.

Ian,

I was having the exact same problem with the gasket in my Squeeze. It was really annoying. Turns out I was actually over tightening it. That may not be the case with yours, but you might experiment with it. For mine, the point where I feel the first bit of tightness is perfect for a good seal that won't leak nor put the gasket in the neck of the bag. Previously I was turning it probably 2 turns further.

Excited for my Mini to arrive!

Ryan

"Turns out I was actually over tightening it. That may not be the case with yours, but you might experiment with it."

If there were a dozen other threads on the gasket (like there is with the bags) then I'd be inclined to blame Sawyer. In this case I'm sure it was my fault.

Lesson learned.

A2.3: Filter Application – Do not over tighten the filter on the pouch. Over tightening can cause the o-rings to embed into the threads or lodge into the opening of the pouch. If the o-ring is out of place you may not a have a tight seal and water could leak out the bottom of the filter. Please watch our video on Important Squeeze Filter Tips to better understand how to care for your squeeze bags. Until you learn the perfect balance of force and cleaning, we recommend bringing a backup pouch with you on your trip.

Thanks for the link John.

"I would much prefer to be able to screw something on both ends."

If I had designed it instead of the fittings it has I ould have put Luer lock fittings on both ends. Syringes have Luer lock fittings on the ends so IV lines or neddles can be attached. You can also buy hose barb to Luer lock fittings.

So if you need to backflush in the field simply twist the syring onto the one compatable fitting. If you want to hook up a hose for in line or gravity use, connect hose barb to Luer lock fittnigs to the filter. If you want to attach it to a bottle use a Luer Lock to thread adaptor (which sawyer would probably have to design). Or they coild put threads on the outside of the filter and then use a threaded male to male adaptor to attach the bottle to eh filter. Package all that up in one box with some 1/4" hose and you would have a very flexible setup that could be easily changed in the field.

Looks like a great option; especially for solo hiking.

I feel like I'm trying to "guild the lily", but can you get reasonable output by hanging a bottle with the mini attached and allowing it to flow (by gravity) into a container? Would you need a few feet of tubing between the dirty water bag and the filter?

Harris, a few feet of tubing between the filter and the clean water bag would work, too. As long as the tubing doesn't collapse, it will function the same way with the filter at the top end of the tubing or the bottom. The water flow rate through the filter will be the same in both configurations. I think the mini could be great for a setup like that.

Colin, I did what you described with mine. I bought hose at Home depot to create a gravity rig that feeds my dromedary bag with and I just use that same piece of hose to backflush.

Great. Looks like epoxy a small piece of nylon tape to form a loop on the bag (for hanging), 2-3 ft of 5/16" tubing, and go-to-go.

You don't need to epoxy anything to the bag. On each side of the new bags at the bottom there are 3 sets of cutouts pressed into the plastic. I just picked one on each side drilled a hole through them and have a short section of paracord routed through it (If at some point it begins to tear I will put a grommet in it). The tubing I got at Home Depot that fits it perfectly is 3/8" on the exterior and the innner diameter is 1/4" and it fits on the outflow nipple of the Sawyer perfectly. The hose is the same size as the fitting for the dromedary drinking tube attachment so I just have to pull the mouthpiece off and use a 1/4" barbed adapter and I can plug it in.

"The water flow rate through the filter will be the same in both configurations."

I don't think that's correct. As long as the tubing is big enough that resistance isn't much of an issue then putting the filter at the end of the tubing makes for a higher column of water and thus more pressure at the filter, so a higher flow rate. I.e. the higher the dirty water bag is above the filter, the higher the flow rate. Whether it's enough to be noticeable might be arguable, perhaps. I'm not an engineer, though, so maybe I'm missing something. (One of my engineer buddies once tried to explain to me how to calculate the water pressure exerted on the bottom of a dam, and it just made my head hurt. It wasn't simply the water column pressure.)

See here, though it regards the older Sawyer filter:

http://www.backpackinglight.com/cgi-bin/backpackinglight/reviews/display_reviews?forum_thread_id=5536&cat=Hydration%20%2D%20Water%20Treatment&cid=55

Gravity mode doesn't make much sense

Filter is 2 or 3 ounces (mini or Squeeze)

Soda bottle weighs less than 1.5 ounces.

It takes a minute or two to squeeze out a pint of water. You can do it at a comvenient location – you don't have to bend over at a stream and pump or anything.

If you use collapseable bag it weighs a little less.

Gravity mode stuff weighs more

Before Squeeze and now mini, gravity mode made a lot more sense.

Well using it in a gravity configuration means I don't have to squeeze the bag so it extends the life of the bag and coming from an MSR filter that weighed 16 ounces my gravity setup weighs less than half of that. I am quite happy with it.

Gravity or not is not a deal breaker, but it would be nice to use as gravity filter while doing other things at a campsite.

I agree. The last thing I want to do is sit and squeeze 4 liters of water into my dromedary for camp use at night/morning.

I have three one liter bottles of untreated water. And 1/2 liter bottle of treated water that I carry.

I don't treat water that is boiled, which is about half.

I squeeze about three 1/2 liters over the course of a day. Not enough hassle to be important. It would take longer to set up and put away the gravity mode stuff and check it as it's filtering.

During the day, I'll probably filter some water and then continue hiking so I'de rather just squeeze it rather than wait for gravity.

When I've done gravity mode, I sometimes forget about it and it runs onto the ground. Good for a laugh when I catch it.

Just seems like most of the reason for gravity mode has gone away with squeeze

For water refills during the day I would squeeze but at camp and connected to the dromedary bag there is no chance that my 2 liter sawyer squeeze bag is going to overflow my 4 liter dromedary especially since its directly connected via a hose.

Hi,

I find that connecting my original Sawyer squeeze filter output to a clean water bottle via a tornado tube to be very convenient.

It appears that is no such threading for a cap at the output of the mini filter which could be used to attach the tornado tube.

Is this the case, and, if so, what to people do–just rig up a bit of tubing to some water bottle cap adapter which can be fastened to the top of a clean bottle.

Thanks,

rhz

Dean said: "I don't think that's correct. As long as the tubing is big enough that resistance isn't much of an issue then putting the filter at the end of the tubing makes for a higher column of water and thus more pressure at the filter, so a higher flow rate. I.e. the higher the dirty water bag is above the filter, the higher the flow rate."

No, sorry, you are misunderstanding hydrostatic pressure, and so was Keith Selbo when he posted his comment in the thread you cited. The filter itself is the rate-limiting stage in the path of the water from dirty reservoir to clean reservoir. You can imagine it like a simple bottleneck. Hydrostatic pressure of a column of liquid can be calculated using the equation:

p = dpg (easy to remember: "pee equals deerogee")

where p is the pressure (Pascals), d is depth from the surface for which pressure will be calculated (meters), rho (the second "p") is the density of the liquid (kg/m^3), and g is the gravitational constant (9.81m/s^2). So, for a three foot long tube (ignoring the water column in the dirty water bag):

p = (0.9144 meters)(1000 kg/m^3)(9.81 m/s^2)
p = 8970 Pascals (Pa) = 8.97 kilopascals (kPa) = 1.3 psi

Because water can, for this purpose, be considered an incompressible liquid, you can imagine the water column in the tube like a rod that pulls down with a force equal to the hydrostatic pressure at the bottom. At the filter, no matter where it is on the tube (the top, the bottom, or somewhere in the middle) the positive pressure from any water above the filter and the negative pressure from any water below the filter will collude to compel water through it at a pressure of 1.3 psi. The position of the filter at the top, middle, or bottom does not matter.

This only breaks down if the length of the tubing below the filter exceeds about 33 feet, if the tubing diameter is extremely narrow (causing a pressure drop due to friction), if air can enter the tubing below the filter (through a leaky fitting, say), or if the tubing is collapsible. If the tubing and all fittings below the filter are airtight, the diameter of the tubing is more than 1/64 of an inch or so, the length of the tubing below the filter is less than 33 feet, and the tubing below the filter is sturdy enough to not collapse, then the flow rate through the filter will be the same whether it is at the top, the bottom, or somewhere in the middle of the tube.

In practice, flow rates might differ due to practical obstacles. It might be easier to have an effective prefilter if the Sawyer filter is at the top, say.