Because there are variables beyond my control (clays, papers, water, mixing errors and etc) always pre test fire what you have before a big project. No guarantee can be offered that 'alternative" commercial paperclays now on the market will meet the all the performance advantages of my high performance trademark P'Clay® brand only available from licensed manufacturers/distributors.
There are two common design systems of porous clay filter
Design System One, (illustrated here) "The Candle" would be a hollow clay form like you see in the pictures here. The fresh fired filter would be immersed in a bucket of "yuck" water and the straw would be hooked up to a hose that will draw water in a bucket through the clay wall in and out by exit up straw to a hose to be delivered to a clean drinking cup.
Design System Two is a "Gravity Feed" It invoves two cups (hand made by pinch, coil or wheel, or cast or press moulded) that fit together stacked one upon the other. Pour water drip drains through the top cup to be caught in the bottom cup below.
There can be imaginative "feet" or handles or spouts attached to cups or the shapes.
A Design Problem for Handbuilding Models of Water Filters:
Classroom Think Tank for Fresh New Combinations and Assembly of Forms by Rosette Gault
A Designers Challenge
To imagine and sketch some fun and interesting looking water filter designs. Many shapes and models are possible. Two systems described in simple at the right. This is real homework. We still need really simple fast low cost filters so EVERYONE can have them not just those who can afford the luxury. Many of the currently available low cost filters are made of man made materials that are not sustainable long term. Let us end this problem on planet earth forever and to move on to better things to do with our time and our lives ot improve health and quality of life.
Make some containers to hold the water (or liquid or gas) to be cleaned. These can be by pinch, coil, wheel, slab, or even slump or hump mold, press mold or even cast.
Make some parts, a lid, feet, a spout, handles, etc. to decorate the containers. Add small flowers or a stamp or date in the clay a regional symbol cultural design, family crest, logo, or symbol to give each design even more individuality.
The child can poke a straw in the soft clay any time during the process. This will dry in place in the model. For a water filter the location of the straw indicates where the clean water in the hollow belly area could be sucked up and out to be connected to a hose that would lead to a clean drinking glass. (If using Design system One see right.)
The soft P'Clay parts will harden in the air overnight or in a few days. The parts can be made first, let dry and and then attached after they are dry in a second session if desired using the P'Slip®.
Dry P'Clay® assembled works are usually tough enough ok to take home and sit on a shelf indoors. The filters could be decorated also but decoration is optional. If parts break by accident they can be reparired or added to when dry.
These are just models of some ideas. Older students can study more technical variables for an engineering challenge.
The pictures below are works in progress from a classroom groups of elementary age children in my class in Gothenberg Sweden at Frolunda Culture Center March 2010.
Bag or slice of P'Clay® ceramic paperclay, drinking straws, little container (reclaimed yogurt or cottage cheese cup with lid) of the paperclay (P'Clay®) mashed in water to make a thinned down paste (P'Slip®) to use like glue to join the parts together. Water clean up. Can be done in one or several short sessions- half hour to hour.