A Lion brand miter trimmer is an essential woodworking tool for creating edging on wood. According to the manufacturer, the blades require sharpening whenever they no longer cleanly cut through the wood, but rather begin pushing it away. When this happens, either you can send the trimmer back to Lion to do the sharpening, or you could sharpen it yourself using a standard whetstone.
Fill a small bucket with 1 tsp. of detergent and warm water. Place the sponge into the bucket.
Unscrew the holding screws on the trimmer using a screwdriver. Carefully remove the blade.
Soak your whetstone in clean water for 10 minutes. While the whetstone is soaking, wipe down the entire blade with the detergent water and the sponge, making sure to remove any sawdust.
Place the blade flat side down on the whetstone and slowly rub back and forth until the flat side of the blade has scratch marks throughout.
Turn the blade over so that the bevel is facing downward. Set the blade so that the bevel is angling downward on the whetstone and begin moving in a slow figure-eight motion. Continue rubbing the blade until it has uniform scratch marks.