Designing Dovetails for Strength and Style
Do I really need to use higher angles when I’m cutting dovetails in softwoods like pine? Does the dovetail angle affect the strength of the joint?
Bill Fontana, Worcester, MA
No. Although softwoods are more compressible than hardwoods, you needn’t change the dovetail angle to add strength to the joint. Any angle between 7° and 15° will work, regardless of the wood. But stay within that range. If you go below 7°, you’ll start to lose the mechanical strength of the dovetail. Go above 15°, and you’ll leave too much short grain at the tips of the tails, which weakens the joinery.
Thin stock is perhaps the one exception. If you’re dovetailing stock less than 1⁄4-in. thick, go with at least a 10° angle. It increases the glue surface and strengthens the joint—but only slightly.
The art of dovetailing is to aim somewhere between those extremes. The…