For a chemistry project titled Student Without Borders, we created a simple product that would help fulfill basic human needs for people who urgently need help. We decided to create a water filter for those lacking clean water in Ethiopia. Learn how to make it below:
Step 1: Collect Materials
- Plywood 1/2 inch thick
- Waterproof drawers
- Nail gun
- Tape measure
- Saws (table and jig saw)
- Metal grate
- Drawer guide
- 1/2 inch wood screws
Step 2: Cut List
Create a cut list showing what lengths each side needs to be cut to.
Step 3: Cut and Attach
Cut out sides, bottom and front to the sizes you decided on in your cut list. The back should slide in between the sides and the structure will be set on the bottom. Add glue to the edges and put into place. The glue will hold it in place long enough for you to add staples down the side. Each staple should be about 2 inches apart. In the end, you should get a cube with no front or lid.
Step 4: Adding Drawers
Cut a hole in the bottom of the top drawer so water will be able to flow through. Glue in the top drawer and add nails through the side into the drawer. This drawer will be set into place. Make sure there are enough nails to keep it sturdy; it will need to hold up a lot of weight.
Place drawer guides on bottom level. Only screw in with two screws on both sides. Attach the drawer. If it is not straight, remove drawer, unscrew the screws and level it. Keep repeating until you are happy with how the drawer sits. Once you are happy with it, screw in five more screws randomly to both sides.
Step 5: Sand
Sand the entire outside. First with 80 grit, then 120.
Step 6: Optional
Stain. This will allow for a nice look and will help to waterproof your filter. We also created dents and scratches in the side and front to make it look more worn.
Step 7: Adding Metal Grate and Fabric
Over the hole you created in the top drawer, add the metal grate. Go around the edge with silicon glue and place the metal grate firmly over the top. Over that attach fabric using silicon glue. The metal grate will help hold up the filtering layers and the fabric will help to remove out any last large chunks.
Step 8: Building the Filter
Bottom layer: 7 liters cleaned separation gravel.
Middle layer: 6 liters of cleaned drainage gravel.
Top layer: 60 liters of cleaned filtration sand.
Step 9: Add Top Sheet
Add another layer of sheet and fabric over the top; it should have a small dip in it so that more water can sit on top and slowly flow through. This will get all the big chunks out of the water and keep the sand from being completely moved around. Once everything is in place, run dirty water through the filter for a month. This will create a good bacteria layer that, once complete, will eat and thrive off of the bad bacteria coming from the water.
Step 10: Finished
Use and enjoy your clean water!