Large holes in 5 easy steps
Follow these steps
Many times when making trays, shallow bowls, or clocks, the need arises to cut large holes. Often the holes are odd-size diameters or irregularly shaped. As you'll see in the following steps, a router, pattern bit, and shop-made template will cut these holes accurately every time.
1. Mark the workpiece
Cut an MDF or hardboard template to the desired hole shape using a jigsaw, scrollsaw, or circle cutter. Sand sawn edges smooth. Now, hold the template on the workpiece and mark the hole location as shown.
2. Rough-out the hole
Using a drill press and 1" Forstner bit set just less than the finished hole depth, hog out as much material from the hole as you can. Be sure to leave the layout line to relocate the template on the workpiece.
3. Reinstall the template
Using double-faced tape or hotmelt glue, attach the template to the workpiece. Take care aligning it with the marked layout line.
4. Rout the hole
Chuck a pattern bit in your router, set its depth so the bit's bearing contacts the template, and rout around the template's hole in a clockwise direction, smoothing the roughed-out edge of the bored hole.
5. Complete the hole
If the hole can be routed to finished depth with the template in place, reset the bit depth and complete routing the hole. If the bit won't safely reach the finished depth with the template in place, remove the template, reset the bit depth and complete the hole as shown.