edges 58 a and 58 b of walls 56 may be chamfered as shown above in fig1 a and 2a to provide sharp cutting edges that may tend to form the irregular gouge in workpiece 12 discussed at ii above or walls 56 may be formed taller and thinner so that they are more likely to bend as discussed at i above it is contemplated to orient walls 56 oppositely so that workpiece 12 threads first into vertical edge 58 b as opposed to angled edge 58 a still further alternatively both edges 58 a and 58 b can be angled so as to meet at an apex located for example at the center of wall 56 in yet another alternative embodiment upper threaded member 52 is replaced via any of the nail portions or nails described herein here upper workpiece 12 is translated or hammered onto walls 56 as opposed to being threaded onto the walls again the edges of walls 56 may be chamfered and have any of the shapes and orientations described above in still another alternative embodiment flathead portion 20 of the upper screw member 52 is replaced with a second set of downward facing saw teeth that also bend or create gouges in the wood as the screw member 18 is threaded into workpiece 14 so as to create a locked fit between the screw member 18 and first workpiece 14 in yet a further alternative embodiment not illustrated screw member 38 having threaded portion 34 is used.