Abstract: A saddle-joint jig for reproducing the line of contact of the first tube in relation to a second tube so that the first tube, when cut along that line, may be joined in end-to-edge abutment to the second tube, in that same relation. The jig includes at least three generally parallel pins, each of which is slideably held to allow each pin to slide longitudinally when a force is applied thereto. The pins are held in a band that, in use, is capable of circumferentially enclosing the first tube.