Robbie O'Brien demonstrates how to use the LMI articulated clamp for guitar repair work.
Sometimes when clamping up a top crack it's nice to have several clamps lined up along the crack so the crack can be made level along its length, and so one can clamp a variety of things underneath, such as loose braces and reinforcement patches. These articulated clamps were designed to reach around each other in a straight line back from the soundhole. They are designed to have two working lengths which makes this task even easier.
There is a V-groove with a pin at the end joint to keep the sections aligned so one can insert the bottom part inside the guitar and drop the upper one on without worrying about the top and bottom mating up at the far end. Even with its full 12" throat, it's easy to stick the bottom section into most any round soundhole guitar.
This clamp has moderate clamping pressure. If a little extra squeeze is needed, a heavy clamp can be easily added on top.