Electric pencil sharpeners work faster than manual sharpeners and are more effective at creating a smooth, even edge to the tip and inner lead. According to DrawingCoach.com, an electric sharpener can turn a blunt pencil into a precision-sharp pencil in only a few seconds, so it is worth building your own. You can show your science project students how it works and how it is an improvement over a manually operated sharpener.
Build your electric pencil sharpener to fit standard 6-mm diameter pencils, as described by the Sundry Memes website. Only use non-standard dimensions of sharpener construction if, for example, you are illustrating how to use carpentry pencils, which have unique dimensions and shapes.
Create or purchase a simple, suitably shaped casing for the sharpener to house the blades safely. A small, hardwood box with a hole at one end is sufficient. Drill a hole in one end at least 6 mm in diameter (if no hole exists) using an electric drill and a wood-cutting drill bit.
Purchase a motor with a power cord from a hardware or specialist store. Affix the two blades to the motor arms at a 23-degree angle to the case of the sharpener, as explained by Online Schools website, using strong glue. Measure the angle of 23 degrees using a protractor.
Measure the distance between the sharp edges of the two blades using a measuring rule. Ensure the blades are 6 mm apart at their sharp edge to give a consistent, conical-shaped result. Glue the motor to the inside base of the box using the glue so that the blades line up with the drilled hole.
Check that the blades are in line with the drilled hole before the glue dries. Adjust the position of the motor if necessary. Press the motor firmly into place. Wait an hour for it to dry. Test the sharpener by plugging the power cord into a wall socket and gently introducing the tip of a 6-mm pencil into the gap between the two rotating blades.
Apply a small amount of lubricating oil to each blade surface. Wipe any excess away using a dry cloth. Maintain the sharpness of the blades by regularly opening the sharpener and filing the blade edges with a small file. Replace old, worn blades by pulling them out with pliers and affixing new blades using strong glue. Dissolve old, tough glue with acetone.
Do not build or repair an electric pencil sharpener while it is plugged in to the main power supply as you may receive an electric shock. Take care when using sharp blades as they can cause cuts.