When you work with plaster, or other materials which form solids, you will have surplus material which ends up mostly in the sink. To avoid that this excess material is clogging up the pipes you use a filter system. The mode of operation of these filter systems is basically always the same. There are three chambers in which the solids settle bit by bit before it flows into the drainpipe. The water is flowing into the next chamber because the boards, which builds the chambers, have different heights. The filter systems available on the market cost between 200€-500€. However, there are also regulations of the municipal authority in Vienna. Max. 10 ml solids per liter may be present in the water that ends up in the sewer water. For plaster, there is an additional limit that applies to sulfate in plaster. Max. 400mg sulfate residues per liter. The sulfate, a mineral, attacks concrete, most sewer pipes in Vienna are made of concrete. Nevertheless I couldn't understand why a a filter system, which isn't that complex must be that expensive. Thats why I built a filter system by my own. My ambitions were: to build a filter system which is easy to make, with easy-to-get materials and after all as cost-efficient as possible. In addition, I created an instruction, that I hope, helps others to build their own filter system.

Images by © Nikolaus Korab

Step 1: Necessary Material for the Construction of a Filter System

* Required pipe (s) and transition / connection sleeve (s) depend on the type of drain and siphon.

Step 2: Necessary Tool for the Construction of a Filter System

Step 3: Instruction for Building a Filter System: A; Tool: Template, Jigsaw Material: Plexiglas

Make a template from the round bucket. use this to cut a circle of the Plexiglas with the jigsaw.

Step 4: : B; Tool: Jigsaw, Angle Gauge, Measuring Tape Material: Plexiglas

Cut two plexiglas boards with jigsaw.

Caution: bucket is conical, length of bottom and top are different. Use an angle gauge.

1.Board

Height 25cm, width: bottom: 29cm, top: 33cm; two slopes

2.Board

Height: 25cm, Width: Bottom: 13cm, Top: 15cm; a slope, a straight line

Step 5: : C; Tool: Jigsaw, Measuring Tape, Sander Material: Plexiglas

Because these two boards will create the three chambers, in which the solids can settle, we need height differences that leads the clean water into the next chamber.

1.Board: Mark the middle and 2cm down. Attention: Cut only the part to the marked center

2. Board: Mark 4cm down

and cut it out

Step 6: : D; Tool: Jigsaw, Sander, Right Angle Material: U-profiles

Trim U-profiles.

- 4x length 25cm 3 pieces with 1x miter.

1x without miter

- 1x length 29cm mitred on both sides.

- 1x length 13cm with 1x miter.

- Miters 45 ° with sander, cut with jigsaw

Step 7: : E; Tool: Drill-with Hol Saw Material: Plaster Bucket

Before we glue, we position the U-profiles with tape to their position.

Go to your siphon, check where your last chamber is and mark the hole on the bucket in which your pipe, which will lead to the drain pipe, is going to be.

Caution: the pipe of your siphon must lead into the first chamber and the hole must be at the last chamber. Drill a hole. Diameter of hole saw adapted to pipe.

Step 8: : F; Tool: Cartridge Presse, Powerful Adhesive Material: Plexiglas Circle

We start to glue. We start with the circle, use the powerful adhesive, generous amount, and press firmly.

The power matters, not the duration

Step 9: : G; Tool: Cartridge Presse, Powerful Adhesive Material: U-Profiles

Small board:

1. U-profile 13cm with 1x miter on bucket bottom. Miter direction to bucket wall.

2. U-profile 25cm with 1x miter on bucket wall. Miter direction to bucket bottom.

Big board:

1. U-profile 25cm without miter in the middle of the glass, where the height gradation takes place.

(for small board)

2. U-profile 29cm, miter on both sides, on bucket bottom.

3. and 4. U-profile 25cm, with 1x miter left and right on bucket wall.

Miter direction to the ground

A T-shape should be created.

Step 10: : H; Tool: Cartridge Presse, Silicon Material: U-Profiles, Plexiglas Circle

We come to the end, we will seal the edges with the silicone. Lead the silicone with cartridge along the circle and the U-profiles. After making lines, put detergent on your finger and squeeze the line slightly to achieve a better density.

Step 11: : I; Tool: Hands Material: Foam Seal

The foam seal makes the empty place between plexiglas and U-profiles tight. So we take for each of our two glasses 2 strips for the front and 2 for the backside. Glue these at all places that will be positioned in a U-profile. Afterwards try out how easy you can get the plexiglas into the U-profile. Is it difficult to get the board into the U-profiles then let the foam seal just on one side.

Step 12: : J; Tool: Hands Material: Garbage Bag

10.

Since the boards are removable, we can put in a garbage bag, and then push the boards into the U-profiles. The garbage bag prevents the solids from drying on the bucket and saves you tedious disposal of the solid residues.