Topic

Funnel and Prefilter

Viewing 25 posts - 1 through 25 (of 34 total)
PostedMar 8, 2023 at 6:50 pm

I am using and liking the Sawyer Squeeze, Smart Water bottles for clean and a 2-liter Cnoc for dirty.

 

There have been occasions where the water was dirty enough that I thought it wouldn’t be a bad idea to have a way to pre filter.

Also, as some of you know, it’s not always easy to completely fill the Cnoc by itself. A dip cup helps.

 

After watching this video

🔵Sawyer Squeeze Smart Water Bottle Mods🔵 – YouTube

I made one as he suggested, ending up with a dip cup and funnel.

The two Smart Water bottle parts, together weigh 1.2 oz, 35g.

 

So now I’m looking for some filter options.

Reading threads here on prefilters, some of the more popular options seem to be some type of thin, flexible filter material or a fine fabric mesh.

Trying to decide how to use one of those with the Smart Water funnel and Sawyer coupling piece.

I’m not familiar with the fine metal mesh but I doubt it is flexible enough to put over the SW threads and screw the coupler on.

Maybe a cloth, fabric type filter material?

Thoughts?

 

Iago Vazquez BPL Member
PostedMar 8, 2023 at 7:35 pm

As the video says, I think a lot of people use bandanas. I never liked dealing with the wet cloth after.

When needed, I used the Coghlan’s Filter Funnel that has a brass strainer at the bottom that filters the larger stuff in conjunction with a scooper.

Thinking along reusable coffee filters, I recently got Montbell’s Compact Dripper 4 (larger than model 2) since at times I take chopsticks backpacking. If no chopsticks,  twigs can be easily put to use where I hike most often. I got it recently and I don’t have as much time on it. What I do like so far is that it’s less of a mess to deal with than a wet bandana.

PostedMar 9, 2023 at 6:13 am

Thanks.

Yeah, I think some type of fine mesh, filter material would be better than a wet coffee filter or bandana.

That’s good to know about the coffee filter being so slow. I’m not familiar with using one.

Jerry Adams BPL Member
PostedMar 9, 2023 at 7:24 am

I think the BPL web software is screwing up the link to that youtube video, I wonder if this works

Youtube video

Jerry Adams BPL Member
PostedMar 9, 2023 at 7:33 am

I just copy pasted the link and did not click the link ikon of the BPL web software

I’ve screwed with cutting up liter plastic bottles, but an unmodified bottle works pretty good in shallow water.  Squeeze the bottle, put the opening under the water – can be just an inch or two, let go squeezing and water will get sucked into the bottle.  This has an advantage over a scoop, in that you can draw in water that’s below the surface where a lot of stuff can be floating.

Maybe pre filtering isn’t that critical.  It will filter out big particles, but they don’t clog up the filter that bad.  Particles that are close to the pore size, 0.1 micron or whatever, will clog up the filter worse.

David Thomas BPL Member
PostedMar 9, 2023 at 9:52 am

“Maybe pre filtering isn’t that critical.  It will filter out big particles, but they don’t clog up the filter that bad. ”

Yup.  That’s been my experience with industrial filters.  In the building next to my office, we treat 40,000 gallons a day and putting a 10-micron filter in front of a 1-micron filter doesn’t change the service life of the 1-micron filters.  Big chunks collecting on the filter element doesn’t prevent nor change the rate at which the smallest particles get deep into the filter and fill it up.

PostedMar 9, 2023 at 2:52 pm

“putting a 10-micron filter in front of a 1-micron filter doesn’t change the service life of the 1-micron filters”

Interesting. I hadn’t thought about it that way, partly because I don’t know what the micron size is for some of the finer filter materials.

I was just thinking of catching some of the fine silt that occasionally can’t be avoided. But I guess it’s just as well to let the Sawyer filter catch it and backflush.

Thanks.

Jerry Adams BPL Member
PostedMar 9, 2023 at 3:38 pm

The Squeeze filter is hollow tubes with 0.1 micron pores in it.  The water passes from outside to inside the tubes.

Any particles much bigger than 0.1 microns will stay outside the tubes.  Of course, this is a simplification because all the pores are slightly different size.

Particles that are much smaller than 0.1 micron will pass through no problem – yummy, extra protein

Particles that are right about 0.1 micron will get lodged in the pores.  If there are enough of them, your filter will plug up and can become unusable.

When you backflush, water is pushed from inside the tubes to outside.  The tube expands slightly because of the water pressure, so the pore size increases slightly.  Particles lodged inside the pores will be washed away, a well as all the big stuff outside the tubes.

Many reports of the Sawyer Mini plugging too easily.  It has fewer tubes and pores.  Some people have switched from Mini to the Squeeze, or Steripen.  Or Befree.  Or…

Gummy stuff or mineral deposits can get stuck onto the tubes and into the pores.  That’s the biggest reported problem I’ve heard about with a Squeeze plugging up.  Backflushing doesn’t help.  A pre filter doesn’t prevent this.

The biggest cause of this is putting hard water from your faucet into the filter, and letting it stay there for a long time.  If you add bleach to the water it’s much worse.  If this happens you can soak with warm/acidic water.  vinegar.  CLR…

I have now summarized an uncountable number of previous threads about this : )

PostedMar 9, 2023 at 5:09 pm

Hey, thanks Jerry and David, for all that good info!

It is appreciated and I think I will be forgetting the prefilter.

 

When you say Gummy stuff or mineral deposits, I’m thinking the mineral deposits come from hard water from the faucet, and I do have hard water at home. Would it be good to use the distilled water I use with my CPAP when cleaning the filter for storage?

Jerry Adams BPL Member
PostedMar 10, 2023 at 8:13 am

some people swear by pre filters, mine is just one opinion : )

distilled water would be good to clean filter.  Maybe backflush with regular water, then just a bit more of the distilled water so it’s left in the filer in storage

or, maybe just avoid using bleach and you’re good, or if you use bleach then flush that out with clear water before storing filter.  And keep in mind the technique to backflush with vinegar, CLR, or warm water if it does get plugged up

PostedMar 10, 2023 at 10:30 am

As the filter “clogs”, larger particles being kept at bay and this accumulation slows down the flowrate.  That being said, the accumulation actually acts as a pre-filter and your filtration levels can actually improve, albeit a slower flow rate.  Backflushing can increase the flowrate by reducing the built up particulates.  My 2 cents.

Bill K BPL Member
PostedApr 4, 2023 at 3:46 pm

thanks for the link to the Mods .. I also prefer a bandana as a prefilter

Seems like every year I try a different system. just viewed gearskeptic series on water treatment and decided to try the Squeeze this year for my hiking in CONUS.

Last year on the SHR I used a steripen ultra and a Fuji bottle (square so does not roll) w/ the top cut off as my scoop/dirty water. Steripen easily fit in for treating water and also for storage along with a bandana.

David D BPL Member
PostedOct 8, 2024 at 1:14 pm

Reviving this thread.

Jerry, you mentioned that storing a water filter wet with a weak bleach solution will block the filter fibers slowing down its flow rate.  Do you have any references for this?  I can’t find anything to back this up online.  I’m talking with Platy right now and they recommend long term storing with a weak bleach solution.

Katy, Sawyer, Platy, they all recommend weak bleach solutions.

My Quickdraw slowed to a crawl this year despite amazing care and I’m trying to figure out how to avoid this.  Platy have been great in support but these late season northern waters have sometimes been tasting like seaweed and fish with just the backup Pristine tablets.

Jerry Adams BPL Member
PostedOct 8, 2024 at 2:47 pm

“Do you have any references for this? ”

I think maybe the case where the filter clogs is when you have hard water and put bleach with it in the filter.  It was in previous thread(s) here.

The bleach (which is basic) reacts with the calcium(?) in the water to form a mineral precipitate on the filter.

Which you can dissolve away with an acid or CLR has some other chemicals too.

I have soft water and backflush with tap water which has a little bleach in it and my filter hasn’t clogged.

If you have hard water you could put a little distilled water in the filter.  Like, you could “squeeze” just a little through the filter as though you were filtering water.

I always shake the water out of the filter when I’m done, that is, the water that’s outside of the hollow tubes.  This probably doesn’t matter?

JCH BPL Member
PostedOct 8, 2024 at 3:35 pm

I’ve been storing a Sawyer Squeeze full of distilled water since March. Tested a couple weeks ago and it flowed like new.

David D BPL Member
PostedOct 8, 2024 at 7:45 pm

“The bleach (which is basic) reacts with the calcium(?) in the water to form a mineral precipitate on the filter”

Interesting, thanks.  I did some searching and it seems you’d need fairly hard water and a long bleach soak for this to happen.

I’ve been using distilled water with bleach for disinfecting my filter and any at home back flushing, so in this case, bleach would be safe (but doesn’t kill crypto).  I follow up the disinfecting with distilled flush and back flush and then dry in front of a high speed fan salvaged from a PC

Adam BPL Member
PostedOct 11, 2024 at 11:03 pm

Just want to say, this is a really useful thread!

A few years ago I had a Sawyer mini and took it to Indonesia with me (work trip). Remote area, filtered silty water in some rainforest near where we were working. Tried black flushing, but my god the flow rate was painfully slow, and it clogged and clogged. It was exhausting especially as I needed water for three of us in hot humid conditions. At the end of the trip I’d had enough and threw the damn thing away!

Seems the Squeeze is a much better option. I watched a video the other day of them being used for years and years by “water women”. It was quite inspiring. So, I’ve ordered one.

In the past I’ve mostly just used chemicals (eg Iodine, especially overseas), or gone raw when hiking in much of Australia.

Viewing 25 posts - 1 through 25 (of 34 total)
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