Figure 10-7. The stop blocks determine the length of the mortise. Full mortise depth is reached by making repeat passes.
Mortises with round ends can be formed with a router bit (Figure 10-7). Mark the stock where the mortise begins; clamp stop blocks to a fence extension to control the length of the mortise in both directions. Position the workpiece against the left stop block so the bit will be at the first mark, extend the quill to penetrate the workpiece, and lock it. Then move the workpiece until it contacts the right stop block. Mortise cuts are usually quite deep, so repeat passes will be necessary. The width of the mortise depends on the size of the bit.
Figure 10-8. Mortises formed with a router bit will have round ends, so the tenon must be shaped to fit.
Mortises formed this way will have round ends; therefore, the tenon must be shaped to fit (Figure 10-8).
Slots-Slots are formed the same way as mortises except that after the quill is extended and locked in position, the cut starts at the end of the workpiece and continues until it contacts the stop block (Figure 10-9).
Figure 10-9. Slots are formed like mortises except that the cut starts at the end of the workpiece.