Mortise & Tenon Design Rules
Tenon Thickness = ~1/3 of stock thickness
Tenon Width = Stock Width - 2 x shoulder allowance
Mortise Depth = 2/3 to 3/4 of mortise member thickness (blind)
Tips
- Choose a chisel size that matches your tenon thickness exactly
- Leave at least 1/16" extra mortise depth for glue accumulation
- For through tenons, add 1/16" to tenon length for trimming flush
- Haunched tenons prevent twist and are ideal for frame-and-panel doors