Dovetail nailing strengthens joints by what action?

• A. Hammering nails in at angles to resist pull-out.
• B. Nailing straight in the middle.
• C. Gluing and clamping without nails.
• D. Using rivets.

Answer: (A)

Angled nails strengthen a dovetail joint by resisting pull-out. When you drive nails in at an angle (toenailing), the nails press the pieces together and must shear through the wood fibers if the joint is pulled apart. This creates a locking effect: the angled path makes it harder for the joint to be pulled straight out, increasing holding power beyond a straight, vertical nail. The dovetail interlock already resists sliding, and the angled nails add extra resistance by converting pulling forces into shear along the nail and the surrounding wood. Nailing straight in the middle offers less resistance to pull-out, while gluing and clamping without nails rely on adhesion rather than this mechanical locking, and rivets behave differently from traditional nails in such joints.