Screw jack - video

[mansworld]

The V-threads are not designed for power transmission as in lead screw, vices, and screw jacks. V-threads are designed for fastening because their sharper V-shape generates significant friction which resist loosening under vibration and load. On the other hand, Square and Acme threads have a larger flank angle, which makes them highly efficient at power transmission with less friction than V-threads.