PDA

View Full Version : homemade water purifyers



coaster
04-21-2003, 00:47
as I look at my pur water purifyer on my sink, I wonder if it would be possible to make a filter contraption with the inserts you can buy for 6 bucks. Any ideas?

Grimace
04-21-2003, 09:39
There is no way those things you buy for 6 bucks would help for anything other than taking out some sediment and a 25 cent bandanna will do that. If you are worried about parasites and viruses you'll need a more expensive filter and/or chemicals like iodine or bleach

tlbj6142
04-21-2003, 09:56
If you want to go cheap. Get some coffee filters, or use a bandana, and a funnel. Get a small dropper bottle (old eye/ear dropper meds, etc.) of unscented bleach.

Scoope/pour "dirty" water across your "filter" into your container. Put 2 DROPS of bleach per qt. Wait 15 minutes. Drink.

You will smell the chlorine. But my informal testing (3 people) has shown that it is difficult for "city folk" to tell the difference between bleached water and city water.

brian
04-21-2003, 23:09
Coaster...are you talking about the PUR home filters. I thought of trying to take one of those filters- they cost like $8, and taking a peice of PVC pipe and make a gravity filter. Do the home filters take out crypo and girardia? If so, it would only be a matter of sealing it well enough so nothing leaked...i wonder if this is doable. It wouldnt weigh much at all, no more than 5-7 oz's max.

Brian

coaster
04-22-2003, 00:24
Actually the filter I have on my sink is a Brita, It screws on the sink nozzel and supposedly purifyes the water that comes out. I wonder if a gravity fed scenerio is possible. Supposedly these inserts are complete purifyers, they cost a little more then 6 bucks as I stated before! Im addicted to the homemade gear, what a great hobby!

Grimace
04-22-2003, 09:08
"The BRITA Pitcher Water Filtration System is not intended to purify water. Do not use with water that is microbiologically unsafe or of unknown quality without adequate disinfection before or after the system. Individuals requiring water of special microbiological purity should follow the advice of their doctor or local health officials regarding the use and consumption of their tap water and BRITA water"

Their filter only takes out mineral deposits which are much larger than parasites and viruses.

Again, The lightest, cheapest sediment remover is the bandanna.

brian
04-22-2003, 10:53
But what if i bought a katadyn hiker replacement filter and put it inside of PVC pipe?? THats a real filter, so is that viable?

Brian

Grimace
04-22-2003, 12:18
I guess so but I dont think it would work very well. Water filters/pumps use pressure to force water through a filter. Not sure if gravity is enough force.

brian
04-22-2003, 15:44
Grimace:
there are 2 options that i can think of if gravity does not work.
1) Syphon- with a 4 foot hose and a 3 foot differential in height, you can create a very strong syphon. If sealed with the pump, this in theory would drive water through, but not very fast. BUT, no work involved. At all. None.
2) Force. Take a 2L platypus. FIll with unfiltered water. Attach to filter. Attach someother container to other end of filter. Squeeze. Clean water comes out other side. Now im sure that this might sound kind of crude and dangerous. "What happens if you squeeze to hard and break the thing??" If you can imagine what happens to it if its in the middle of your pack, then you shouldnt be worried about popping it. And if you are worried about an old platy popping, then go buy urself a "real" filter. And pump.

1 more thing about pumping. THe pumps you see on todays filters are made so that you dont apply too much pressure to the pump and break it. Actually, its so u dont break the pump action. They use mechanical parts (levers) to make it easier to pump. You are not really exerting that much force upon the water. I bet a syphon would work just fine to run water through a filter, granted its at least 3 feet higher than the filter and its sealed. I might go to Campmor and buy a katadyn hiker filter and try it. If not, then ill have a katadyn hiker filter sitting around. I dont mind.

Brian

Grimace
04-23-2003, 09:06
I am not to familiar with the physics behind a syphon so I'll take your word for it. I can still play Devil's Advocate though...

Your homemade filter will now consist of pvc pipe, filter, rubber o-ring or glue or something to seal the filter in there. Maybe an extra platy bag and something to fill it or maybe 5 feet of rubber hose. I'm just thinking of weight, size, and ease of use.

MOre on ease of use. The reason I resorted to filtering was because during the dry year I hiked in it was hard to find places to scoop water from. It was easier to pump. Would you be able to put one end of syphon hose directly in source or would you have to elevate it?

brian
04-23-2003, 11:02
THe Katadyn(PUR) hiker filter is 2inches in diameter, w\ an O ring on the end to form a seal w\ the filter casing. I would get a 2" diamter PVC pipe(this is just the filter houseing), but it down to about 4 inches, and then seal the "good" end to prevent contamination.

More on syphons: To start one, you take your tubing, and start sucking water to get it flowing. THen you can a)seal it off and then connect to the platy bag or b) very quickly drop it down to keep the flow coming. You can try it from your sink to your toilet or bathtub. The main point of the syphon is to fill the platy bag easally and quickly. So you can just get the syphon going, put the end of the hose in the water, but the platy on shore, and wait for it to fill up.

Next, you attach the end of the hose that was in the water to the dirty end of the filter. Squeeze, or even sit or gently stand on the platy. THe pressure SHOULD be enough to force water through the filter. Thats the one part im a little unsure of. I might be able to get a hiker filter this weekend, so that is where i would put through its paces.

THe good thing about the syphon is that you dont have to stand there, bending your back to keep the filter hose in the water. YOu just get it started and then let it fill up. And now that i think about it, you would only need about 2 feet of tubing. So if the hiker element weighs 3.5 oz, the PVC pipe weighs lets say 3 oz, the 2 feet of tubing weighs 1 oz, the extra platy bag, which might already be included in your equipment weighs 2 oz. So for 9.5 oz, maybe only 7.5 oz, you have a pumpless filter which can suck water out of even puddles with no back breaking pumping of hanging over your water source.

Now you might be asking..."well how long does this take...it sounds complicated!??!"

No more complicated than any other filter. You put ur pack down. Take out the platy bag and hose. Start syphon(15 secs). It takes about 45 secs to fill a 2L platy bag, so while its filling, you go back to your pack and find your clean water bag\bottle, as well as the filter (no time lost). You see the platy bag is filled, so you go over to it, and stop the syphon by simply lifting it out of the water. YOu hook the hose up to the filter, hook your clean water bag up to the filter via another short hose, and gently sit or stand on the platy bag. Water is forced through the filter and into your clean water bottle. Im not sure how much time it would take to filter, but i can imagine somewhere around about 1.5 mins a liter. but i may be way off!?! I will try to get an element this weekend.

Brian

Grimace
04-23-2003, 12:07
you'd better take pictures. You may be on to something.

brian
04-23-2003, 12:14
Im getting a filter today at dicks....same price as campmor....more later

Brian

RagingHampster
04-23-2003, 12:29
You'll still have to chemically treat after filtering unless you use a "First Need" cartridge. No other filter is certified to remove Virus'. Treat your water like towns do for tap water, screen & treat with chemicals. I'm using a $0.50 plastic walmart funnel, cone-shaped coffee filters (thats the prescreen treatment) and AquaMira Chlorine Dioxide, which is tasteless and eliminates all cooties (including virus').

Using my cookpot to scoop water (I boil untreated water for cooking anyways), this makes a great system when their is adequate water. When water is scarce, a pump comes in real handy. To acommodate this, I have a stripped first need pump mechanism with hosing and a Sweetwater Siltstopper 2 pre-filter (which eliminates the need for the cone and coffee filters). With this system I prefilter the water through the siltstopper, and then treat with aquamira. We had one hell of a winter, so I don't think I'll be using the pump very often unless it gets dry towards fall. The funnel/coffee-filter setup weighs less than 2oz for the funnel & 12 filters in a ziplock bag. A set of aquamira chemicals weighs 3oz (even though they reportedly weigh 2oz).

brian
04-23-2003, 17:04
I got a filter......it is infact 2" in diameter....still have to get the pipe

Brian

brian
04-23-2003, 18:19
WOW...using a syphon w\ the water 6 inches above the filter, i got a very steady trickle of water...AND NO PUMPING!!

But my ONE gripe...i was using it backwords...would the filter work the same forwords as it does backwords?? I was putting water in through the out entry...cuase its got a hole for the tube. I dont htink this matters, nor will it affect things. Tomorrow...off to the hardware store for PVC pipe.

Brian

brian
04-23-2003, 22:45
Just a note before i hit the sack.

i tried using the filter backwords (not sure if this makes a difference, but its the best i can do till i get the pipe) using 3 feet of gravity in a platy bag. HOLY $hit!! It works better than squeezing it!! If it works just as well w\ the housing going the right way, this is a great gravity filter...i think. The problem w\ other filters is that the pump stops water from flowing, so it cant flow w\o the pump moving.

More on this tomorrow when i get some PVC pipe from my local hardware store.

Brian

coaster
04-23-2003, 23:16
how about finding 2 threaded sockets (same size as the platy) that you can epoxy(?) to both ends of the filter. Screw in a platy on both ends and do the gravity thing. Also theres gotta be something lighter then pvc...???

brian
04-24-2003, 09:24
Im going to the hardware store today. I need a non threaded piece of something that is 2" in diameter and 4 inches long...and a peice of something threaded that is 2.25"in diameter for the threads on top....coaster...i will definatly look for lighter alternatives

Brian

brian
04-24-2003, 22:06
http://www.whiteblaze.net/gallery/showphoto.php?photo=1007

http://www.whiteblaze.net/gallery/showphoto.php?photo=1007

THere are 2 shots of my new homemade water filter.

THe 1st picture shows a picture of the in\out ports for the tubes. Blue is in and clear is out. THe water enters the side of the main chamber and flows through the filter. It then flows into the blue tube and into the container it is supposed to go to.

Problems THus Far:
1) Ive been playing around with it, and decided to just get an endcap tomorrow for the open end. THis MUST be sealed 100%, and its the only way (and the correct way) to seal this.
2) With a 3 foot tube, this should work as a gravity filter, or if u squeeze the platy you are filling from, a pretty past "normal" filter. I havent been able to really test it becuase the open end, is well, open.
3) THere is a very small amount of leakage from the threaded end of the filter, and this worries me a tad. THe threads both apear to be identical, but they must not be. Im going to buy some teflon tape to see if this helps it. I will also check to see if the currently non used O rign on the filter can seal this.
4) It weighs a little over 9 oz w\ element. THis is final weight however, becuase it incorperates things that might already be in your pack; an "incamp" platy for use w\ dirty, oviously your clean water container, and the hose from your clean water container. The only extra thing it requires is a 2 foot hose to take dirty water from the "Dirty" platy to the filter.

I tried to look for lighterweight material, but it a) doesnt hold up as well b) didnt come in 2" diameter:mad:.

So by 12noon EST, i should have this thing up and running, hopefully w\ good results!

Brian

max patch
04-25-2003, 09:40
Personally not convinced that this is necessary or even practical for one person backpacking use (if group camping in one location then large gravity filter (available commercially) makes sense). REI has a gravity filter setup that uses your existing filter. I suppose you could use it at night and have your morning water available. Or just take a couple minutes and filter it manually. Filtering water is really no big deal. $30 or so.

http://www.rei.com/online/store/ProductDisplay?storeId=8000&catalogId=40000008000&productId=9725806&parent_category_rn=4500459

tlbj6142
04-25-2003, 09:40
They do make "foam core" 2" PVC pipe. It is significately lighter than normal 2" PVC pipe.

brian
04-25-2003, 10:18
Max Patch: that "filter" setup is just 2 bags and the connections to the filter. Im basicly building the casing for the element. THis IS filtering manually, but w\o the pump. And it only takes a little longer. The main point of me doing this is i dont want to spend tons of money on a filter if i can make the same thing at home. It weighs 2 oz less than the katadyn(PUR)hiker, and w\o the element, costs only around $4, not counting platy to collect dirty water. BUt its not $60 for the pump, casing and element. Its only $28. And ANYONE w\ a right mind could build this thing. I just have to get it finished. and the platy system you showed me weighs 9 oz, which weighs as much as my filter does!! 4 liter capacity just isnt needed for 1 or even 2 people. 2 LIters is a good amount for a group from 1 to 3.

Tlbj6142: i was just at my local hardware store (small), and not at a home depot or lowes. I didnt have very much selection. Ill look into that though.

Brian

brian
04-25-2003, 14:39
Im going to take my belt sander to the outside of the PVC and buff off alot of the extra pvc that isnt needed. I got a cap for the end, so it seals now. I just have to wait for the glue to cure (1-2hrs) to officially say how it works

Brian

icemanat95
05-20-2003, 23:11
You've given up the ability to pump fast when necessary and gained...nothing...the first time I saw someone set up a PUR hiker to siphon filter was in 1995. You've saved a bit of weight...maybe and saved a few bucks once you factor in the cost of the filter and the materials for the housing.

Not that it's not a good idea and you've shown ingenuity and initiative building the thing, but as a practical thru-hiking solution, I think I'd just go with the PUR hiker. It weighs 11 ounces dry, it's compact. It's a proven design and it is versatile. All-in-all a good unit. But it's fun to play with stuff and figure out if you can make it better.

Have fun and thanks for sharing your project.

RagingHampster
05-20-2003, 23:13
You still need viral protection, so don't forget a chemical treatment such as chlorine dioxide.