Intro: DIY Hydration Bladder
In this how to we take a liquid bladder from either a coffee box or a wine box and turn it into a reusable drinkable hydration bladder for a back pack.
Step 1: Materials
Okay here's a picture of the items I got to start this.
- Franzia 5 liter wine bag (empty)
- Plastic epoxy
- Water Filters for Brita Drinking bottle (this is the hard-sided version)
- 3/4 inch poly insert with male threads
- 1 1/4 sch 40 bushing with female 3/4 threads
- #8-32 nylon screws
- rubber grommet 11/32 x 1/8
- 3/4 inch rubber repair pipe
- 3/4 inch sch 40 PVC adaptor
- 3/4 inch sch 40 PVC Threaded cap
- 1/4 inch vinyl tubing (4 feet)
- rubber repair tubing with pinch closure (on hand, can't find it in the store)
Total cost was about $35 for this instructable, but it will filter water without having to do anything else. Plus, it holds more than a standard Camelback. It's gravity fed, and pressure serving (meaning that the weight of the water will send this out to your mouth, and you can suck out the rest).
It took me about 5 hours to find everything, and I had to look in diverse places such as the irrigation systems for a sprinkler setup and the plumbing sets. Most of this is also force-fit rather than glued, but there are a few pieces that are glued down to make sure that there are no leaks. So let's get started.
Step 2: Bladder
Okay, this is probably the best step.
1. Go out and buy a box of Franzia Wine (I chose the 5 liter version) or a box of coffee.
2. Drink up.
3. Once you sober up or come down off the caffeine high, pull the friction fit spigot off of it, rinse out the bag completely and drain fully, fill with air and make sure it dries completely.
Probably the easiest thing to do. You really want to get all that wine or coffee out. The goal here is to have a bag that is completely dry and completely water tight. So whatever you do DO NOT PUNCTURE THIS BAG or you will have to do this over.
Step 3: Start Assembly
Once you have everything, you take the bushing that will fit AROUND the hole in the bag and reduce it down to 3/4 inch threaded pipe. I used all plastic for this as it would be easier to connect and would ultimately weigh less. The bushing I got here was the best option I could find. The threads in it would allow me to use the L pipe with the connector and the screw threads.
You want to glue the bushing to the bag with the epoxy. But you DO NOT want to glue the L pipe down since that is how you will be filling the bag. The idea here is to have something you can grab and twist off, fill with water, and then screw back down.
The filter housing is the black pipe. This particular filter has no housing on it so you have to make your own. The way the filter works is explained in the next step.
Step 4: Filter and Housing
Okay, first off you want to cut the black 1 1/4 inch pipe to length. This is the length of the top part of the L connector AND the filter. It has to be long enough for the filter to fit down fully.
The filter has to have room around it to let the water coming in from the bladder to flow in through the charcoal into the inner pipe where it is sucked out through the tube. It's the flowing from outside to in that filters the water. Because of this we have a couple things that we need to do.
In the Brita water bottle, the housing has a "backwash" one way valve. The bottom of the filter sits against this one way valve, the water is pulled in from around the housing, into the inner pipe where it goes out the mouthpiece. We have to plug up that hole.
I couldn't find anything that would fit in there completely, so I improvised by buying the rubber grommet to fit in there, and then seal it up with the nylon screw. This kills the backwash ability, but it keeps the pure water separated from the contaminated water in the bladder.
So, carefully fit the rubber grommet into the hole, and then slowly screw the nylon screw into the grommet's hole. That is that part.
Next glue the 3/4 inch connector with the male threads to the end of the black pipe. Glue this down tight.
Take the cap and put a hole in the middle. This will be where the mouth piece pipe sticks out so you can suck out the water. Make is a little bit larger so you can fit the tubing down in that fully and so it won't pull free.
Place the filter in the tube, screw the cap down. This is your filter housing done.
Connect the drinking tube. Here you go.
Step 5: Drinking Tube
Okay, the black tube with the pinch valve. Push it down into the vinyl tubing as far as you can.
Cut it to length, and put the pinch valve on there.
Step 6: Done
Now all you have to do is to let all the epoxy cure and then use it.
My thought is to wrap one corner around a small stick and use a couple binder clips to attach it to the inside of my backpack. This will let it be supported and it will allow me to drink from it. The force fit on the nipple end of the filter and the black pipe will be a bit problematic, but it can't be glued into place due to having to be replaced. The black pipe is force fit to the L pipe, and it's such a tight fit that I don't think it's going to leak there. I may have to buy some rubber O rings to seal around the top of filter and where it sits with the male fitting. That's a place where it may leak, but I'm hoping not. The cap screws down so that we can replace the filter as we need to.
I'd love to hear from any of you who make this and use it what you think.
I'll add to this as I need to once everything is cured and being used.
Step 7: Edited to Add
Okay, let everything cure as it should, and filled it up.
First thing, it leaked around the top of the filter, like I thought it would. I solved this by cutting a leather "washer" to fit around the top of the filter and seal that up.
The other leaked around the bushing glued to the bag. This was a bit unexpected, but easily fixed as I reglue all the connections to make sure there isn't any leaks. Other than that there was nothing wrong. It worked as I had supposed it to.
Now to get a nice pack to put it into and to use it as it should be.