Cap screw counterbores are tools that are used to create a recess in a workpiece for the head of a cap screw. You might use a cap screw counterbore when you need to attach a component to your workpiece using cap screws, and the component has a thickness that is greater than the length of the cap screw.
Another reason you might use a cap screw counterbore is if you want to create a flush or countersunk appearance for the heads of the cap screws on your workpiece. A cap screw counterbore allows you to create a recess in the workpiece that is sized to fit the head of the cap screw, giving the screw a flush or countersunk appearance.
Overall, cap screw counterbores can be useful when you need to attach components to a workpiece using cap screws, or when you want to create a flush or countersunk appearance for the heads of the cap screws on your workpiece.
