High Quality Bits

Leigh Brand carbide-tipped router bits are among the best you can buy. They are made with high quality C2 and C3 micro grain carbide for long bit life. Each bit is honed to a fine edge with 600 grit diamond wheels for smooth, efficient routing. All shanks are 1-3/4" long to handle the thickness of the finger assembly or accessory template. Leigh router bits are manufactured to ISO 9002 standards.

All box (finger) joints are routed with straight bits and Leigh offers two variants: a two flute spiral upcut both in High Speed Steel and in Solid Carbide. The spiral upcut design routs cleaner, faster, leaves a smoother finish and dramatically reduces tear out. Although both produce excellent results, the solid carbide versions are stiffer and hold a keen edge longer than the HSS. The performance of less expensive HSS bits is comparable to Solid Carbide but lose their edge more quickly. Choose the bit that best suits your needs and budget.

Shank Size
All box (finger) joint bits with a cutting diameter of 1/4" or less, have 1/4" shanks and can be used in standard 1/4" collets. Bits with a cutting diameter greater than 1/4" will have a shank size equal to the cutting diameter. For example, the 170(C) bit has a cutting diameter of 5/16" and the shank size is also 5/16". A router with a 1/2" collet is required for 5/16", 3/8" and 1/2" bits. A collet reducer is also required when using a 5/16" or 3/8" bit (see collet reducers below).

Box Joint (Finger Joint) Bit Selection

While there are no hard rules, bit selection is based first on board thickness. In all cases, the cutting depth of the bit (see column B in Bit Selection chart) must be equal to the thickness of the pin and socket boards. When boards of different thickness are joined together, the selected bit must have sufficient cutting depth to accommodate the thickest board.