Standard drywall screws or Confirmat?

Cabinets of every size and shape are assembled with coarse-thread drywall screws and yellow glue—it’s fast, reliable and cheap. So why would anyone spend twice the money for fasteners that are harder to find and require a special drill bit?

When a cabinet or built-in may have to be taken apart, or when a stronger joint is required, Confirmat fasteners might be worth looking for (photo right). Häfele, the German hardware and fittings company, bought the patent and originated the name some 25 or 30 years ago and produces Confirmat fasteners for the cabinet trade (with the patent expired, so do a lot of other companies). According to Karl-Heinz Kraft, product manager at Häfele’s North Carolina plant (800-423-3531; www.hafele.com/us), Confirmat fasteners differ from standard wood screws in two ways: a shank size that is roughly double that of a typical wood screw and a thread style that allows the screw to be backed out and reinserted dozens of times without loss of strength in the joint.

Confirmat screws replace two-part cam-and-bolt connectors often used at right-angle joints in knock-down furniture and cabinets. They are less expensive, less complicated and stronger, Kraft says. The heavy upper part of the shank essentially turns a Confirmat fastener into a removable metal dowel. Kraft says the threads are designed to compress material, which allows a Confirmat to be reinserted into the same hole without cutting new threads. In medium-density fiberboard or 45-lb. particleboard, a Confirmat would hold after 30 or 40 cycles, says Kraft. Performance in soft woods won’t be as good.

Confirmats are available in lengths of 40mm, 50mm or 70mm (roughly 1-1⁄2 in., 2 in. and 2-3⁄4 in.), and in shank sizes of 5mm, 6.3mm or 7mm (about 3⁄16 in. to about 9⁄32 in.). Phillips and Allen-wrench drives are available, as well as cover caps for applications where the screw head will be seen.

Extra-strong cabinet screws

Confirmat screws (left) are heavier than the coarse-threaded drywall screws often used in cabinet assembly (right). Confirmats can be removed and reinserted numerous times without weakening the connection.