This instructable takes a very short time to complete and doesn't require much in the way of materials. Chances are, most materials are on hand.
Step 1: Gather Materials
- Coffee Filter
- Acetone & Cloth
- Ball Inflation Needle
- Ball Inflation Pump
- Sharp Utility Knife
- Permanent Marker
- High Density Polyethylene (HDPE) Container with Lid
- Hard Surface
- Shaggy Surface
- Place the lid on a shaggy surface, such as a carpet. You should be able to rotate it freely without it moving off its axis.
- Hold a permanent marker to the inner edge of the lid and rotate it to make the outline of the circle to be cut.
- Cut the circle with a sharp utility knife. Don't press too hard or the plastic may crack. You may want to predrill the lid, or use a Dremel routing bit instead.
- Use acetone to wash off any residual markings left by the permanent marker.
Step 3: Cut Filter
- Flatten the filter and fold it in half as many times as possible so that only 1 lid can be traced.
- Trace the lid at the very top corner of the folded sheet with pencil and cut.
- Unfold the sheet. Try to trace the lid again at the very top corner and cut if able to do so.
- Unfold the sheet. Again, try tracing and cutting.
Step 4: Assembly & Use
- Using the tip of the utility knife, rotate a very small puncture into the center of the filtering container.
- Push in the ball inflation needle.
- Put a filter into the cap such that it touches each edge of the lid when inserted.
- Fill the container half-way (below the needle) with fluid needing filtering.
- Cap the container with the filter-lid.
- Invert the filter over a capturing container.
- Apply pressure to the ball inflation needle.