Cutting Mortises With a Drill
Save door-chiseling time with a Forstner bit
Here's a way to quickly make hinge mortises using a Forstner bit and a cordless drill. You need a chisel only to clean up corners that the bit can't reach. Select a bit diameter that's about two-thirds the width of the mortise: Anything smaller takes too much time, and anything bigger requires more chiseling.
1. Mark the hinge outline. Place the hinge on the edge of the door with the knuckles pointing in the direction the door opens and mark around its perimeter with a pencil. Score this line deeply with a sharp utility knife.
2. Mark the mortise depth. Hold the edge of the hinge against the bit's lower edge. Take a felt-tip marker and mark the bit using the edge of the hinge as a guide. This will show how deep to drill. Repeat on the bit's opposite spur.
3. Drill the mortise. Place the bit square to the edge of the door and just inside the hinge outline. Drill slowly until the line on the bit reaches the surface of the door. Stop and drill again in an adjacent spot so the holes just overlap. Work methodically across and along the length of the mortise, always keeping part of the bit next to an untouched surface. Without that reference, there's no way to know when to stop drilling.
4. Trim the waste. Holding a chisel bevel-side up, with one hand on the blade and one on the handle, slice away any wood that the bit couldn't reach. Work from the knuckle side in until the mortise floor is flat.
5. Test the fit. Place the hinge in its mortise to see if it's flush with door surface. If not, drill or chisel until it is. Then you can fasten the hinge and move on to the next one.
Where to Find It:
Lee Valley Tools
Lee Valley Model #06J80.07