If you are like me and been wanting for a water filtering system for your back country uses and couldn't bring yourself to spring for the money then now there's a chance to have a full functioning water filter for about a third of the price of the commercially available models. It's nothing against those products they are great systems that I have used many times. This was a fun project and can save money and is built solid and is customizable to make any size you want. The one in this instructable is quite large that I made mostly as a prototype and I plan to use for when I am in my base camp. Now that it turned out good and functions well, I plan to make a smaller version for taking on backpacking trips. ***Disclaimer*** If you choose to make this filter and do use it to process your drinking water you are doing so at your own risk. Drinking water that has not been boiled can always be a potential danger for disease and bacteria. If you do get sick I hold no liability or responsibility to the outcome of your decision to make and use a water filter *** Disclaimer*** That being said I have used it and been just fine because I believe in the process that I used to make it. I think this is a good effective system for a low cost that can provide us with the most precious resources that we have, and why I am fortunate to live in the lake states and have fresh water everywhere I know that not everyone has that luxury. So this was part of my inspiration for this project, thinking back to the times I have been in the western desert states and water that was good to drink was hard to come by. With this system nobody would have those concerns. Anyway, Build it and enjoy if you want. Either way thanks for reading. Also as a note I added my original drawings that I made before I even started the project. They are pretty rough and not very accurate based on the final product, but I thought I would put them up for any use they may be.
Step 1: Tools and Materials
So it's a bit of a lengthy list here, there's a fair amount of tools and different parts needed to put the whole thing together. There are definitely different ways to do it both for tools and materials used. The following list is just the combinations and methods I found works best. Feel free to experiment and try different things though.
- Wire cutter/Snips
- Tape Measure
- Dremel bit 561
- 5/32" drill bit
- Ice pick/Prick punch
- 7/8" socket
- 7/8" wrench
- Purple primer
- PVC cement
- Zip ties
- Screen Mesh(Preferably Nylon)
- 2 inch schedule 40 PVC
- 1 1/2" schedule 40 PVC
- 1/2" by 3/4" reducer or sink aerator
- Coffee filters (50)
- 2" threaded PVC cap
- 2" male thread adapter PVC
- 1/2" muffler clamps(4)
- 1/2" compression nut(2)
- 1/2" pex thread adapter(2)
- 12 MM siphon bulb
- 1/2" clear vinyl tubing
- Faucet Screen
- 1/2" brass flush adapter
Step 2: Making the End Caps
Now to start I made the end caps for the main filter body. There are two that need to be made, the threaded one and the non threaded one. The process is the same for both and not very difficult. Just be slow and easy when making the hole and it will be fine. Or as you see in one of the pictures it can break quite easy, but the method that broke the cap is not the method I used to make the hole as described here. So lets get started.
- First find the center point of the cap, best way to do this is by clamping it in a vise if you have one and measuring from each side. I would recommend using a rag in the vise to minimize damage to the cap. Don't worry though it doesn't need to be the exact center.
- Now that you have the approximate center, draw a circle with your marker approximately 3/4". Then take your prick punch if you have one and make a starter hole for your dremel bit. Or if your like me and don't have a prick punch then take your ice pick and give it a wack with hammer to make a hole.
- Next is to take the dremel with the multi purpose cutting bit and cut out the hole. Be slow and keep the speed low because the PVC can shred pretty fast and you can't fill in the hole, but you can make it bigger if needed.
- So with the hole cut out take the hose stem and thread it into the hole of the cap, it should be tight and a struggle to thread into. Then take the compression nut and thread it on the inside of the cap.
- I now chose to do a leak check and found that it was still leaking a little. It wasn't a big deal and wouldn't affect the performance but it would annoy me.
- So lastly lets get some silicone and spread it around the inside of the cap to seal off the nut. Hopefully the picture shows the silicone good enough.
Step 3: Making the Main Filter Body
The next thing that we will be doing is making the main filter body. It's pretty easy and not much work, and can't really be screwed up. This is when you first get an idea of what the filter is going to look like as a whole. As a note I recommend wearing the gloves when gluing the PVC together.I didn't bother and usually don't remember to do it when working with PVC. To my knowledge the glue and primer don't hurt you in anyway, but I am not a doctor. What I do know is that the purple stuff takes days to go away from your hands and the glue is not much better, hence the gloves.
- First step is to cut the 2" PVC to length of 12 1/4". Make sure to check the length overall when the caps are on as well. Easiest way to do this is just measure, draw a line and take it off with a hacksaw. Then take your knife and scrape off the saw shavings left behind.
- Now take the non threaded end cap and apply the primer to the cap and one end of the pipe. Then apply the glue to the outside of the pipe and quickly put the cap on to the pipe. Give it a few seconds and then pull to make sure it is tight.
- Next is to take the threaded adapter and put the primer on the inside and the other end of the pipe,then apply the glue to the pipe again. Quickly seating the adapter to the pipe and checking it for proper connection.
- That is all we will do with that for now, until we get the hoses assembled and the filter made.
Step 4: Foot Valve Tube
Next step is to make the foot valve tube to put on the main filter body. For the record that name is not really accurate, because it's not a foot valve it's really just more of a strainer and weight. I just called it a foot valve because that is what it is on a suction hose for a pump and I wasn't sure what else to call it. Anyway this is going to serve the purpose of keeping the hose weighted down and to strain out the majority of the sediment and muck that your filter could suck up. Keeping with the theme I kept it simple and easy to do because I wanted anyone to be able to make this.
- First you need to cut the tubing, any length that you want is fine. I went with about a foot.
- Then take your brass reducer or sink aerator if you went that route and place the faucet screen in it.
- Now mark a spot on the hose for where your flush adapter will sit. Then you can silicone that section of tube that the adapter will be on. This ensures that adapter will not get lost or fall off the hose in some muddy Appalachian puddle or some other local watering hole you might be visiting.Once the silicone is applied just slide the adapter onto the tubing and let it sit while the silicone cures.
- In about 24 hours when the silicone is fully set you can thread on the reducer with screen. Now your first tube is done.
Step 5: Output Tube
So this step is about the same as the previous one just a little different parts used is all. This is the tube for the other end of your filter, it is wear your clean water will come out, so you will want to keep it separate from the other tube so that there is no worries of contamination.
- Again the first thing to do is to cut the tubing to the length you choose. Like before the length is optional, I made this one about 18 inches long.
- So congratulations on making the cut, now it's time to cut it again. I chopped it right about the middle of the tubing it seemed like the most natural spot. This is where the siphon bulb is going to go, which if you didn't know is how the water will get sucked up through the filter and out the clean water hose.
- With the cut made you can stick the tubing onto each end of the bulb and tighten a muffler clamp down on each piece of tubing. With that your second and final hose is now complete for your water filter.
Step 6: The Actual Filter
So now it is time to build the actual filter, the most critical part of this whole project. It is the heart of what we have going here, what makes it more than just a pile of plastic and brass. This is the piece that will give us the clean drinking water. Don't worry though this is still a easy to do process, the hardest part will be to make the charcoal. You might wonder why you can't just use the charcoal from the store. Well what we barbecue with is sadly not just burned wood. I don't know what it is but I assume there's something nasty in it. As far as the liquid charcoal at the pharmacy, well we need a solid for this to work. Also it's fun to make, so grab a beverage and some meat and watch the wood burn. Now I am not going to show you how to make the charcoal here because there is already a vast wealth of information on the internet about it and there are people who can explain it better than me. So show some love to the others like us and learn a new skill if you don't know how. You'll be glad you did, there is endless uses for it once you know how to make it.
- So first thing that I did was to get some coffee filters and accordion fold them. I ended up only using around 30 of the originally stated 50. Once you have them all folded loosely zip tie them together, and do not cut off the ends yet. We will tighten the zip ties later on.
- Now we must cut our 1 1/2" PVC to length. The length you will want is 11". Once you have it cut take the drill and make a bunch of holes throughout the pipe. These will allow water to pass through to the filter better. If you want you could get creative here, although it would only be for you because it won't be seen. I just did a simple line up and down the pipe, but feel free to do stars or your name or a unicorn if you want. Life's all about having fun after all. A note that in one of the pictures you'll see I am using a hammer handle to clean up the drill shavings left behind. That worked OK, but I'm sure there are other ways to do it.
- By now you should have made your charcoal and let it cool, I crushed mine up to small pieces about the size of class 5 gravel(like what you see in roads or driveways)as I found they fit best with the filter system.
- What you want to do here is cut a piece of screen mesh 9 1/2" square. Then fold all the edges in so the loose strands and rough edges are gone. Then dump your charcoal into the mesh and wrap it like a tortilla. Now zip tie it together and cut the zip tie ends off.
- Then put the charcoal filter inside the coffee filters and tighten and trim the zip ties.
- Lastly put the whole filter inside the 1 1/2" PVC pipe.
Step 7: Final Assembly
Well now that we are nearing the end hopefully you have worked up a good thirst. There isn't much left to do here.
- First put the filter inside of the main body.
- Then put the threaded cap back onto the main body of the filter.
- Now make sure that each piece of tubing is connected to it's barb with a muffler clamp and tightened down. You can trim the excess off the clamps with the snips if you like, or you can be like me and leave them because my backpack already has holes in it anyway.
- So if everything is put together and tightened down then it should be good to go, so find yourself a sink or a pond and let's do a test run. I suggest the sink for the test just in case of technical difficulties.
Sadly I have no test photos because my camera battery died, and I also didn't want to drop the only camera I have in a tub of water. My Results were better than I really thought they would be though. On the first test I had no leaks and was able to pump one gallon of water through in about six minutes. Which seemed good to me for a little hand siphon bulb. What I found worked best was to put the whole filter body into the water and leave only the output hose out of the water, that seemed to allow for the best suction. Again though experiment and see if you have better luck. After all that's mainly what this whole project was for me, was just an experiment that worked good.As far as price goes I was able to make the whole system for about $25, which is significantly less than buying one of similar function. So that's it, hopefully by now you have clean delicious water and the urge to go find some mudhole to drink out of 30 miles into the wilderness. Or if not whatever you find as a great source of water and adventure. *** Again you do assume all risk that goes along with water from sources of potential contamination. Myself nor any other person or party is not to be held responsible.*** Hope you enjoyed the project and thanks for reading.