How to Process Tapered Thread by Ordinary Lathe

Machining cones with movable tailstock is only suitable for workpieces with pin holes at both ends, and cannot be used for machining inner conical surfaces (tailstock thimbles have nowhere to top).

By adjusting the spindle box, the spindle makes an angle with the guide rail of the lathe bed, which is convenient for machining inner and outer conical surfaces and tapered threads. However, the headstock will return to normal after adjustment, and if it is not adjusted properly, it will directly affect the machining accuracy of other workpieces in the future, not to mention the taper of 130mm long, 150mm big end and 120mm small end, which seems to be less than that of ordinary lathe headstock.

Generally, the copying machine is used: install the copying machine on the lathe bed, remove the lead screw of the middle carriage, connect the middle carriage with the copying machine in a proper position, fix the small carriage at 90 degrees to replace the middle carriage to complete the feeding action, and adjust the angle between the copying machine and the guide rail of the lathe bed so that when the big carriage moves 130mm, the middle carriage moves under the constraint of the copying machine15. Taper or taper thread (including internal thread and external thread) with the same taper is directly processed, but it is fed by a small carriage, and the middle carriage is constrained by the copying die to process the conical surface.

The advantage of using the copying die is that after use, as long as the connection between the middle carriage and the copying die is separated and the screw is put back, the lathe can work normally without readjustment.