Randha Machine With Chain Attached

For cutting larger mortises such as those used in timber frame construction, chain mortisers are commonly used. A chain with cutters (similar to a chainsaw chain) rotating within a frame clamped to the work is successively plunged into the workpiece to mortise out the required volume.Here's how: An auger-type drill bit spins inside a hollow four-sided chisel secured to the mortiser. The bit itself locks into a drill chuck inside the head of the machine. When you pull down on the mortiser's feed lever, the bit and chisel plunge simultaneously into your workpiece.