How to Build Rain Gauges With Cups
- 1). Select cups that are see through or opaque so that the water level can be measured with a ruler. Plastic cups with straight sides are best for attaching rulers. Be careful not to select cups that will disintegrate when exposed to water for long periods of time, like paper cups.
- 2). Attach a ruler to the outside of the plastic cup using a rubber band. If the cup is too short to hold a ruler, make a ruler out of paper. Paper rulers should be laminated so they will not be directly exposed to the water. Attach the paper ruler to either the inside or outside of the cup using clear weatherproof tape.
- 3). Create a rain gauge holder using a clothes hanger. Fashion the lower part of the hanger into a few loops that will support the bottom of the cup and any water that it collects, along with support for the sides. Attach the hanger to a fencepost using a hammer and nails.
- 4). Check the rain gauge once every 24 hours. Dump out collected water after taking measurements. Clean out the cup to make sure no debris such as dirt or bugs build up in the cup, which could alter the readings.