Valve Thread Mandrel - 3676

For Besson Tuba Top and bottom threadsThese Valve Thread Mandrels don?t have any abrasive or cutting action. They are basically a forming tool to reform threads into their original positions, smoothing up any burrs or waviness. Because of their solid design, these Valve Thread Mandrels can be started on a ruptured part more easily than if they were slotted. They have a hex handle which makes them easier to control than a T handle. Our Valve Thread Mandrels leave a smooth burnished finish that can?t be obtained from any case hardened cutting tools.The number listed in the chart below tells the size of the mandrel. The first two numbers indicate the thread pitch and the last two numbers indicate the diameter in 64ths of an inch. NOTE: In most cases you will need at least two P100 Mandrels to repair damaged threads. One mandrel will be the actual size of the horn as listed below and the second will be 1 size larger for external thread or 1 size smaller for internal thread