A nut includes a nut body that defines a circular hole, and that has four driven wall portions and four guiding wall portions disposed about a central axis of the nut in an alternating arrangement. The driven wall portions are equiangularly spaced apart from each other. Each of the guiding wall portions is straight, and has two opposite ends that are respectively connected to two of the driven wall portions adjacent to the guiding wall portion. A ratio of a longest distance between two of the driven wall portions that are non-adjacent to each other to a longest distance between two of the driven wall portions that are adjacent to each other is greater than 1.16. Each of the driven wall portions has a curved section and two straight sections. A central angle of the curved section of each of the driven wall portions is smaller than 180 degrees.

A device for use with a wood-based structural element having an outer surface and inner surfaces defining a T-slot, wherein the T-slot has a central section that is open at the outer surface, and has a pair of undercut sections projecting from opposite sides of the central section, and the inner surfaces of the structural element include a pair of inner surfaces facing inward, the device comprising: a T-nut having an outer portion receivable in the central section of the T-slot, a screw-threaded bore, and an inner portion with a pair of clamping surfaces projecting from opposite sides of the outer portion; wherein the bore has a nominal cross-sectional area for receiving a threaded fastener, and the clamping surfaces on the T-nut have a combined surface area of about 10 times the cross-sectional area of the bore; and wherein the T-nut is configured for use with a wood-based structural element.

An edge clamp for use in clamping a workpiece to a fixturing plate, wherein the workpiece includes a top surface and one or more side, the edge clamp comprising: a body having a top surface, wherein a clamp portion extends laterally from the body, and wherein a stabilizer portion extends downwardly from the body; an aperture extending through a thickness of the body from the top surface; wherein the clamp portion includes a lower surface having at least one clamp pad, and wherein the stabilizer portion includes a side surface having at least two registration surfaces separated by a stabilizer groove.

A device for use with a wood-based structural element having an outer surface and inner surfaces defining a T-slot, wherein the T-slot has a central section that is open at the outer surface, and has a pair of undercut sections projecting from opposite sides of the central section, and the inner surfaces of the structural element include a pair of inner surfaces facing inward, the device comprising: a T-nut having an outer portion receivable in the central section of the T-slot, a screw-threaded bore, and an inner portion with a pair of clamping surfaces projecting from opposite sides of the outer portion; wherein the bore has a nominal cross-sectional area for receiving a threaded fastener, and the clamping surfaces on the T-nut have a combined surface area of about 10 times the cross-sectional area of the bore; and wherein the T-nut is configured for use with a wood-based structural element.

A split coupler, and methods of making and using such a split coupler, whereby the split coupler includes a first semi-cylindrical member, a second semi-cylindrical member, and an interlocking assembly configured to interlock the first and second semi-cylindrical members to form a substantially cylindrical coupler having a coupler inner surface which defines a throughbore. Additionally, the split coupler can include spiral threads coupled to the coupler inner surface. Furthermore, the split coupler can include a flange inwardly extending from the coupler inner surface.