Also known as a 'birds mouth" bit, a Multi-Sided bit is a great way to join a wide variety of multi sided projects, such as planters, columns, and barrels. Very straight forward, this joint requires routing a single notch in one edge of each stave (board). The notch improves ease of assembly and total glue area. Once assembled, projects can be left flat sided, turned, planed, or sanded to the desired shape. Bits should be used in a router table with a fence.
The #R3506 works for both 6 and 12 sided objects with material up to 7/8" thick. On 6 sided objects, the exterior side is cut face up on a router table. 12 sided objects are cut face down.
Either flush or ribbed (outside corners protruding) construction is possible. Ribbed construction is recommended with 12 sided objects because the interior leg of each notch will be very small when made flush. If desired, outside corners on ribbed construction can be cut or sanded down for a flush appearance.
Location of the inside corner of the notch (i.e. vertical bit adjustment) is important for final finish appearance. The outside leg of the notch (closest to the exterior) should be the same length as the stock thickness for flush construction. This will put the inside corner of the notch in the center of the stave on 6 sided flush projects. The inside corner will be below center (furthest from exterior side) on all others. Allow extra stock to experiment and set corner height as desired. Move notch towards exterior side (raise bit) to increase rib size (amount of outside corner protruding). Move notch away from exterior side (lower bit) to decrease amount of rib.
NOTE: Bit adjustment is reversed on 12 sided objects since those staves are cut face down. Carbide tipped. Double flute. Whiteside Machine Company - Claremont, North Carolina.
SH = Shank Size. LD = Large Diameter.
1/2" SH X 1-7/8" LD