I'm curious. I have a pair of box-jointed pliers made by CK. If I was to remove the pin from the joint in the pliers, the joint still wouldn't come apart because the shape of the two halves of the joint holds it tightly together. I can only assume that the two halves start out as three forged components, which are then ground and assembled, and lastly a permanent joint is made somewhere by hot forging or resistance welding. But the joint isn't visible at all. I've seen a similar joint in some monkey wrenches, but it's not so intriguing as the monkey wrench can still be taken apart.
Does anyone know how this is achieved?