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Hy2U for washing hands: Manual Hy2U, how I make it
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Manual Hy2U, how I make it

Lists of steps to explain and photograph or video

(Add description anytime we work on a certain part and know again how it it done)
  • 1. Tools to be acquired, borrowed or bought
  • 2. Tools to be specially made for making the Hy2U
  • 3. Materials to be collected or bought that will become a part of the Hy2U
  • 4. Instructors and Instructions needed to use and make the Hy2U
  • 5. Instructions for later use and upkeep, how to instruct others to use it
  • 6. Parts of the Hy2U:
  • - 6.1 the cloth bag and parts attached to it
  • - 6.2 the valve board and parts attached to it
  • - 6.3 the waste water collecting bag

    Category 1. Tools to be acquired, borrowed or bought

  • For sewing and working with textile: a sewing machine, a few needles, chalk to mark, a sharp pair of scissors,
  • For wood working: a cutlass with a file or sharping stone, a metal hack saw with a new sharp blade, a bit of sand paper or broken glass.
  • For welding the plastic waste water basin: an iron, a table and a batten (see manual)
  • a sharpening stone for manually sharpening knives
  • a fine file to sharpen the cutlass or other knife for working wood

    Category 2. Tools to be specially made for making the Hy2U

  • a template for marking the size of the cloth front and back part
  • a template for making the size of the plastic waste water basin
  • a special drill made from a bicycle spoke
  • a special drill that can drill holes of 9 mm, made out a short piece of rebar, diameter 6 mm.
  • a sharp knife made out of a broken half of a metal saw blade, 10 to 15 cm long with a strip of rubber wound around one end as a handle, such a strip cut from a car tire, witdth 8 mm, length 30 cm.
  • A piece of rebar, lenth 30 cm and diameter 5 mm to burn holes is wood.

    Category 3. Materials that will become a part of the Hy2U and should be collected or bought

  • Cloth for the front and back parts of the water bag, 2 pieces larger then 31 cm x 35 cm.
  • Additional cloth to make the bag nice in a decorative personal way.
  • 2 Wooden battens, final size 25 cm long, 4 cm wide and 2 cm thick or sticks to cut them from
  • a short 4 cm diameter stick to cut the valve pipe from
  • Bamboo, with a wall thickness of 3 mm for the strips that keep the cloth bags into a flat shape
  • Bamboo with a wall thickness of 6 mm to make the valve stem from. This can also be any other kind of wood.
  • Small piece of hin plastic foil for the waste water collector basin, as used in larger shopping bags, 0,1 mm to 0,2 mm thick
  • Small piece of regular foam plastic as used for matrasses and upholstery
  • Two thin market shopping bags, tested to hold water without leaking

    Category 4. Abilities that I have to use or have to learn

  • Sewing
  • Shaping wood with a cutlass
  • Drilling wood with a spoke, then making the hole larger with a hot iron rod

    Category 5. Instructors and Instructions needed to use and make the Hy2U

  • Someone that can help with sewing, possibly owns a sewing machine, or someone that can patently instruct you when you are not handy with a sewing machine or can do sewing at all.
  • Someone that is handy with wood working, who can instruct you how to sharpen a knife, knows to differ the bad quality of wood from wood that is useful for use with the HywU
  • Someone who knows where to find materials, such as rubber car inner tires

    Category 6. Instructions for later use and upkeep, how to instruct others to use it.

  • A poster that shows in detail how the Hy2U is used and kept clean. This poster can be downloaded as a pdf from the Hy2U web site, it consists of a number of A4-size pages to be attached to a rope (see 'Manual on a rope')
  • A person that has taken up the task to help people use the Hy2U- hand washer. This person checks that people install the Hy2U at the most appropriate place in their living environment. She or he makes sure that user know how to repair and adjust a leaking valve.
  • A video CD, that explains everything about the Hy2U. How to make it, how to use it, but foremost how people judge about the longer term use of the Hy2U: does it make a difference in comfort? Or in health? Does it stand up to rough treatment? Do people use it inside the house because it looks nice or is it a facility that is outside the house. This story preferably in the local language otherwise in the formal language of the region.
  • A manual that explains the same as the video-CD, that uses the principle of 'Manual on a String', otherwise also gives background stories of the use of the Hy2U.

    Category 7. Parts of the Hy2U and how I make them ...

    1. the cloth bag and the parts attached to it.
  • - .1 the cloth bag itself, composed out of
  • - .1 - front part, cut from cloth using the special template, that is part of the manual
  • - .1 - back part
  • - .1 - cloth strips to hold wood strips
  • - .1 -set ropes to hang it it the wall
    .1 the cloth bag itself, composed out of
    2. the valve board and parts attached to it
  • - 2.1. the board itself, composed out of 2 battens 25 cm long, 4 cm wide and 2 cm thick with a notch that later will hold the valve pipe and holes for joining the two battens together with 2 wooden pins
  • - 2.2. the valve 2.3. the valve itself, composed out of the following parts: (possibly superfluous as in detail described here under)

    How I cut the battens for the valve board from a stick

  • I find 2 sticks of good wood, 40 cm long, clean it from bark and soft outer layer of wood, make sure core is hard, make sure to select a part without nodes. With the cutlass I give it a rectangular cross section of 4 cm by 2 cm. over a length of more then 25 cm, Then I cut or saw it off, with a length of 25 cm.
  • I make sure that both battens are of identical size and have a flat and smooth surface.
  • With the bicycle spoke drill I drill holes 4 cm from the ends. then I enlarge these holes with a red hot iron of mm diameter.
  • With the cutlass or with the hack saw I make identical notches exactly in the middle of the two battens. Each notch is 1,8 cm wide and 1,5 cm deep to have a tight fit for the valve pipe.

    How I cut the valve pipe from a stick

  • I find a stick of good fine grain wood, 25 cm long, clean it from bark and soft outer layer of wood, make sure core is hard, make sure to select a part without nodes. Diameter after cleaning is 4 cm.
  • With a cutlass I cut carefully a length of 9 cm of the stick to a smaller diameter, 3 cm. I take care it becomes really round and hardly flat cuts are to be seen.
  • I teach myself with a little exercise to cut a notch in the wood at the place indicated in the drawing. First of all I make sure the knife is very sharp. A sharpening stone or vile is under reach to assure easy cutting. I also know where to find First-Aid materials in case I would cut myself accidently.
  • I check from time to time the size of the notch by trying to insert it in the corresponding notch in the battens meant for the valve board.
  • I continue refining the fit, until it fits nicely. I take care to prevent exerting force as this could easily split the wood. Instead I make light saw-like movements with my long knive that I keep very sharp. Progress goes with small chips and a lot of patience.
  • When a good fit of the two battens and the valve tube is achieved, I tie the tree parts in position with an elastic rubber strip. Then starts the most important bit of wood working that may not go wrong. Study first what should be achieved: a nice disk-like end of the valve that will be smouth, flat and softly rounded. If done well, it will make a good cushion for the little plastic piece that is the actual valve to rest against.
  • Now I start making an undeep groove in the valve pipe. I realize what this groove is for: it is to hold a thin string of rubber that is wound around the plastic of the thin market bags to create a water tight seal. I start by letting my long machete slide over the board to make an undeep cut in the valve pipe in line with the top of the valve board. Then I remove real small chips to create a groove that is not more then 3 mm wide. The groove will not be deeper then 3 mm. I make the groove smooth with the rubbing it with the teeth of the metal saw blade, that can act as a fine file.
  • The last part is most difficult as it easily can spoil the job: I have to remove the excess wood beyond the disk. Again I make a circular groove, just above the first one. I make that groove deeper and deeper, until the end falls off.
  • As a final touch I make the top smooth and soft to touch, there are no burs or irregularities to be felt. .

    How I make a hole in the valve tube to guide the valve itself

  • The hole valve pipe is big enough to guide the valve while water can flow out, so it has a very loose fit. But the hole is not bigger than that as this would hinder the thin valve to close properly. Reason that I am going to be very careful with the drilling. Result must be that the hole is nicely in the middle AND that the opening at the valve seat side (top side) is not bigger then the hole itself.

    How I make the valve, that little stick with a plastic disc that has to let water out, but may not drip

  • 2.3. the valve itself, composed out of the following parts:
  • - - the valve stick with the two little holes at the top and narrowed to to a thin stick at the other end.
  • - - a foam plastic disk the size of an Euro cut from a mattress or upholstery
  • - - a tiny piece of plastic as used for the bigger size shopping bags, that is 0,1 mm thickness.
  • 2.4. a thin plastic shopping bag, the kind you may tear from a roll or big stack of such bags, thickness is 0,05 mm. , not much thicker, not much thinner. Prior to use, this bag has to be tested to hold water without leaking.
  • 2.5. a square piece of car inner tire, 5 cm x 5 cm, a bigger hole in the middle, two small holes in the corners, a thin rubber strip fastened to each hole

    How I weld together bit of plastic sheet to make the waste water bin

    3. The waste water collecting bag

    In practice people just put a bucket under the Hy2U to collect waste water. There is a better way to do this. Study the big picture at the home page of the Hy2U-website. There is shown how a self-made plastic bag it attached under the Hy2U. This works fine and soon this manual will be updated to describe how this waste water collector bag is constructed from plastic sheet with the help of an ordinary flat-iron and baking paper.

    Category 8. How I finally mount together all the parts of the Hy2U and make it working

    8.1 Attaching to thin plastic bag to the valve board
  • I take a thin plastic bag and fill it with clean water and hold it for a minute. If it leaks even a little, I pour the water into the next plastic bag, until I have found one that does not leak. From now on I am very careful with this special bag.
  • I prepare the thin rubber elastic strip that has to tie the plastic bag to the nipple of the valve board. I do this by making a loop with the rubber strip around my finger and winding the rubber strip 4 times around and around its own loop. At the end the 2 free ends of the rubber strip stick out of the loop at equal length. I hand this to my helper
  • I take the completed valve board and ask my helper to hold it top-side up. I take up the non-leaking plastic bag, kind of roll up de sides, so I can hold and properly see the bottom of the plastic bag. I notice the weld at the bottom of the plastic bag and I notice the two corners of the bag that have a special fold. Now I select the special location at the bottom of the bag that I want to attach to the nipple of the valve board. That location is in the middle of the bottom, so halfway the two corners and just next to the weld.
  • I stretch that piece of plastic between the fingers of my two hands and pull it over the nipple.
  • My helper hands me the rubber loop that I pull over the nipple. With this action I attach the thin plastic sheet of the bag to the wooden nipple. The rubber strip embeds itself deep in the groove. If the loop was made to small, it will be difficult to get it over the nipple, in that case make the loop slightly larger. If it is too loose, make the loop a little smaller. It should be just easy to apply, I exercise until I can do it in one quick movement.
  • I realize that the plastic has to flow over the wooden nipple completely smooth, no wrinkles are allowed. I pull a little at the plastic of the bag, until this is done. I have to do this with care: do I pull to hard, that the plastic will pull of the rubber from the nipple or I may tear the plastic and then I have to start all over again. < Now it is time to mount the valve in the valve tube. I take up the valve at its thick end and place the thin and of the valve batten on hole under the plastic. I push the valve down to pierce the plastic and make the hole still a little larger with a see saw movement of the valve batten in order to make the plastic not fit without free space around the valve stem. I realize that water has to pass here when the valve is up, while this it the very opening that the plastic disk of the valve has to close when the valve is down. I also check if the length of the valve stem is right: it should stick out 5 mm from under the valve tube. With my finger I can push it up at that place, so the
  • Now I can understand what the loose ends of the rubber string are for: I take them up. knot their ends together and pull the knot up to let it rest in the V-groove at the thick upper end of the valve. I now can also feel if I made the knot at the right spot in the 2 rubber strings: if to short I have to push hard to lift up the valve. If to too far to the ends of the strings, the valve does not close easily.
    I pay good attention to get this right as this is crucial for good functioning: a light push with the tip of my finger to the valve stem should lift and open the valve, moving away the valve closes immediately.
  • Now I want to know it the bag is properly mounted to the valve board and if the valve works without leaking. With one hand I hold the valve board, and with the other hand I pull up the handles of the thin plastic bag. I ask my helper to pour a little water into the bag. No leakage, then a little more water. If this test is passed, I pour out the water and I feel save to continue assembling the board in the nicely finished cloth bag.
    8.2 Inserting the valve board into the cloth bag
  • As a start we, my helper and I wash and dry our hands as we want to keep everything neat and clean. As I myself hold the valve board with the plastic bag now attached to it, my helper holds up the cloth bag. Then I lower down the board at an angle into the bag. Halfway down with the board, I make sure that the valve tube will slide through the opening that is made for it in the bottom of the cloth bag. Then I push the board further down, until its corners fit tightly into the corners of the cloth bag. Once again I take great care that the thin plastic bag can follow the board without hooking up or getting jammed. As I have to make sure all works well, I move very slowly. Only when I have gathered some experience, I dare to work swift. 8.2 Inserting the bamboo stips onto the cloth bag
  • The bamboo battens can now be inserted. I remember that these bamboo strips are to give a flat shape to the cloth waterbag. This to make it look nice and keep is clear from the wall when hung. I choose to put 5 bamboo strips in both front side as well as the back side of the cloth bag. I insert the bamboo strip in one of the little pockets that came into being under the textile line vertically at the side of front and back part. of the cloth bag. To insert the other end of the bamboo strip in the opposite pocket, I have to bend the bamboo strip. Would I do this in a rough way, then the bamboo would most probably crack. But taking care to make it bent over its full length, then it can work well. If it turns out that the bamboo is too stiff, then I take a sharp thin knife and make the bamboo a bit thinner and thus more flexible.
    8.3 Attaching the thin ropes to the cloth bag for hanging it accurate horizontally from a wall
  • I have studied how the waterbag will be hung from the wall by an arangements of three loops of thin ropes. This is done in a way that the bag can be hung perfectly horizontal, by just sliding the loops over each other into the right position.
    First I attach 1 end of rope of 25 cm to each of the little sticks that are attached to the top op the cloth bag. Then I take a third end of thin rope, about 50 cm long, let it run through both loops and then knot securely the end together.
    When I hang the completed Hy2U with this third loop on a nail in the wall, I find that I can adjust the Hy2U that it hangs perfectly horizonta. Now I can pour water in the bag. It will hold about 4 liters. Check if the nail can hold that weight. Close the plastic bag by just pushing all of the bag into the cloth bag. In this way he plastic bag will be closed of for mosquitos and dust.

    Hy2U for washing hands: Manual Hy2U, how I make it
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