Pocket screw

In joinery, the terms “pocket screw” or “screw in a pocket” refer to a special method for fastening wooden parts.

The technical name is angled screw joint with countersunk recess. The screw’s length and diameter are selected based on the dimensions of the parts being joined, and the thread pitch depends on the hardness of the material.

Fine pitch is suitable for ash and oak, while coarse pitch is for softwoods and composite materials.

Features

Ready-made kits are manufactured for concealed joining of parts of a specific thickness. The kit includes the following items.

• Drilling jig for pocket screws. The fixed part of the collapsible fixture has two angled guides for the drill bit, with chip-clearance holes positioned opposite them. The movable part slides along the guides, with a travel length matching the thickness of the wood panel. The moving part is secured with special flag bolts, set according to a linear scale with millimeter graduations.
• Step drill bit. The thin section drills the hole for the screw shank, while the thicker section drills the “pocket” for the head.
• Depth stop (attachment for the drill bit).
• Long bit for the power driver.

Application, installation rules

Pocket screws are used to assemble joinery products: tables, cabinets, shelves, and furniture frames made from plywood and timber battens. To make the joint, the drill bit is inserted into the jig’s guide so that there is at least 2 mm to the movable part, and the depth stop is fixed on the drill bit. The jig is placed on the workpiece, pressing the movable part against it, and secured with a clamp. Two holes are drilled, then flat-head Kreg screws are driven into them using a power driver with a long bit. Thanks to its large contact surface, the head sits tightly against the bottom of the stepped recess without splitting the wood.