Routing perfect slots
For arrow-straight slots with crisp, clean ends and edges,
let your router table, a few shop-made accessories, and
a little know-how help you produce on-target results.
Drilling end holes and sawing out the waste between them is one way to form a slot. But success depends on your unwavering ability to follow the straight cutlines connecting the end holes with a scrollsaw or jigsaw. Here's a better method that eliminates the risk of wandering off course.
1. Lay out the slot
Draw slot boundary lines on the part, extending the end lines to the edges.
2. Position the fence
Chuck a slot-size bit in the router. Place the fence to center the bit in the slot.
3. Set the right stop
Align the slot left end line with the left edge of the bit. Position and secure the right stop.
4. Set the left stop
Align the slot right end line with the right edge of the bit. Position and secure the stop.
5. Add an auxiliary guide
Using the part width to gauge the distance, clamp an auxiliary guide parallel to the fence so the part slides easily between the guide and fence.
6. Drill out the waste
Using a bit 1/8" smaller than the slot width, drill overlapping holes inside the layout lines. Drilling an undersized rough slot lets you rout a clean finished-size slot in one easy pass.
7. Make a plunge cut
With the right end of the workpiece touching the right stop, lower it onto the spinning bit.
8 Rout the slot
Feed the part to the left until it hits the stop. The auxiliary guide keeps the part in line.