What Is a Square Hole Drill?
A square hole drill is a power tool used to make a hole in a wood joint. In wood joints, the convex protrusion is called a tenon and the hole into which the tenon is inserted is called a tenon-hole.
The process of making a tenon involves the use of a saw. Until the advent of electric tools, holes were made using a chisel.
The square hole chisel consists of a square box chisel with a sharp tip like a knife, inside of which is a circular drill. After making a circular hole with the drill, the chisel is shaped into a rectangle with an outer square box.
How to Use Square Hole Drills
After marking the area to be drilled on the wood, fix the wood on the drill stand and drill the hole. It is important to firmly secure the wood to be drilled and confirm that it will not move before starting work. If necessary, braces or sleepers can be used to support the material.
When drilling several holes in order to make a long, vertical hole, first drill both ends of the hole. If holes are drilled from one side first, the square hole drills may run away to the side that is already open at the final stage, making it impossible to drill the hole vertically.
When making a through-hole, drill from both sides of the front and back because burrs will form if the hole is drilled through all at once.
How to Select Square Hole Drills
There are two types of square hole drills: stationary types and drill stands that are used by fixing an electric drill to them. The stationary type is a costly power tool and is used in woodworking shops where it is used frequently. For home use or infrequent use, square-hole drill adapters are attached to the drill stand.
In addition to the square hole drills for drilling holes, the stationary type includes square hole drills for drilling holes to insert plugs, and a chain drill for drilling holes to penetrate through holes.
Drill stands differ in electric drill neck diameter, capacity, and maximum stroke depending on the product. A model with the appropriate capacity for your work should be selected.
Some stands can be used for a wide range of drill neck diameters from 38mm to 45mm, while others are limited to 43mm. The neck diameter of the electric drill to be installed should be checked beforehand.
Drilling capacity refers to the size of the chisel that can be installed. It is indicated as a maximum square hole of 12.7mm (1/2″), a minimum square hole of 6.4mm (1/4″), and so on.
The maximum stroke is directly related to the drilling depth, which is selected based on the depth required in the process or the thickness of the wood to be processed.