This really cool-looking edge clamp works great for repairing cracks in the tops and backs of stringed instruments, but the average woodworker might not find it very useful, unless he regularly needs to repair cracked wooden bowls, vases, or other thin curved objects. In that case, this $140 tool just might come in handy.
The lightweight clamp’s adjustable jaws can hold curved pieces between matching convex and concave pads which pivot to match the contour of the surface. To operate the clamp, secure the jaws on either side of the crack, and crank the large thumbscrew to bring the edges of the crack together. If the crack edges don’t align in the same plane, you can adjust either side up or down in the jaws to close the crack.
Herdim makes the edge clamp from a titanium-colored aluminum alloy and uses brass for the thumb-screw adjustments. The 19mm deep jaws open 8mm wide, with double guide rods to keep the jaws precisely aligned. The whole clamp weighs just 113g — about 4oz, for the metric challenged.