If you are making a plaque or a picture frame and want to integrate a slot into the project so that the user can easily hang the piece on a wall without having to use hanging hardware, there is a special router bit called a keyhole bit that can be used for this purpose. The key to successfully hanging your project is as simple as learning how to use a keyhole router bit. The process of learning how to use a keyhole router bit is really as simple as understanding the basics of how to use a router table, being very careful on your bit height, fence placement, feed rate, plunge onto the project, and controlled lifting off of the workpiece following the cutting of the slot.
Some things to be careful about when cutting slots:
Bit height. You need to be sure that you do not go too shallow, and leave behind a fragile wall, or too deep and require too much extension of the fastener out of the wall.
Feed rate. You will feed at a slow, controlled rate so that you leave behind a smooth and straight surface. If you go too fast and the slot wanders, it could make it difficult to accurately position the workpiece on the wall when you hang it.
Plunge and lift. These are the most critical steps in the process, and you will need to be sure that you are moving the workpiece straight up and down as you are learning how to use a keyhole router bit.