How to Use a Forstner Drill Bit?

May 15, 2021

How to Use a Forstner Drill Bit

Forstner drill bits are the perfect tool to create flat bottom holes and overlapping holes. Forstner bits also drill vertically into sides angle, making hole positioning and spacing smoother than any other drill bit.

Forstner bits are used to cut accurate, large-diameter holes. These bits have a wide range of applications.  Although Forstner bits are a little fragile they can break at excessive speed or by applying too much pressure on them. The size of the bits affects the speed and control of a drill press. 

Forstner high-speed steel (HSS) bits do not easily lose control, and Forstner bits tipped with carbide are more durable. 

How to Use a Forstner Bit With a Portable Drill

For Forstner drill bits you will need at least 3/4 inch thick scrap lumber or plywood, few clamps, and a Forstner bit set. Basically, when drilling the actual hole in the wood plywood, you're making a little jig that keeps the bit from moving.

  • Cut a piece of scrap wood or flat plywood sheet in a standard size, by allowing enough space for clamping.
  • Now established your drill with a Forstner bit that you will use on the workpiece. Make sure the bit is properly extended so it can dig through the scrap wood in an easy way.
  • To a sacrificial board, clamp the scrap lumber. You'll be drilling through the scrap, and to reduce tear-out, the sacrificial surface will act as a backer board.
  • Start drilling through the scrap piece into the cavity. It's all right if the bit walks a little at first; once the main cutters engage the wood, it will cut a clean hole. For best power, keep the drill speed slow.
  • Drill through the scrap all the way, holding the bit as vertical as possible (plumb). Get the bit back out and unclamp the residue.
  • Clamp the jig to the ideal spot on your workpiece. To complete the hole, drill directly through the hole in the jig and into the workpiece.

Read - Forstner bit Vs. Spade Bit

Uses of Different Types of Forstner Bit

1. Carbide-Tipped Forstner Bit

Carbide tipped Forstner bits are designed to work hard and long in the tough material like MDF and plywood. Carbide-tipped Forstner bits are perfect for drilling concealed-style hinge-mounting holes. They have a long life span carbide bits can drill into melamine very effectively.

2. Overlapped Holes Bits

These Forstner bits cut overlapping holes (as seen in picture). Cutting a workpiece with overlapping holes is an effective method for the removal of the maximum amount of waste material within a specific shape. It keeps minimum to the chisel work and elbow grease. 

3. Pocket Screw Hole Bits

Drilling screw holes with a Forstner pocket screw hole bit and a drill press is a blessing. Shallow pocket screw holes such as this are also used to connect a top to a table or to drill out where screws are concealed for joints.

4. Large-Diameter Forstner Bits

These Forstner bits are used for drilling accurate, large-diameter holes. It is an ideal choice for clockmakers to create small clock sized holes. Although,  these large-diameter bits are much expensive. So if you are looking for drilling an individual hole for one-time use it is better to use a hole saw (a less expensive cutting tool).

5. Eight Style Forstner Bits

Eight style Forstner bits are unique bits to create medium-sized partial holes. Such partial holes are used to attach a tabletop to an apron, or for secret image mountings on the edge of the board. A Forstner is the only drill bit capable of drilling such a unique style of holes.




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