Out of all types of hinges, the most difficult to fit in the body of the furniture and in the door are the tin hinges.. These structures, in addition to the main can, can also have two pins to eliminate rotation of the fixed hinge. With such a construction, it is therefore necessary to prepare as many as three blind holes, respectively located in relation to each other. However, their wrong spacing will make it impossible to mount the hinge. To mark the location of the holes, you need to make a simple marking device that can be moved to the edge of the door.