The R-390/ 390A use set-screws that are designed for a much higher torque application.
It is known as a "Bristol-Spline" screw head. It may look like a hex or a little like a TORX but the internals are all right-angles instead of triangular or hexagonal faces. The old Xcelite tool-set included Bristol-Spline bits, back in the day most people had no idea what to do with the Bristol Spline bits. The reason for Bristol-Spline is that when tightened it will not cam-out (strip) like a hex bit will. *Ms. Tisha Hayes, AA4HA* ______________________________________________________________ R-390 mailing list Home: http://mailman.qth.net/mailman/listinfo/r-390 Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
