What is the optimal screw drive shape (such as philips, internal hex socket, or slot) that will allow the maximum amount of torque to be applied without having the drive hole stripped? The torque can be applied to the drive hole like in a philips head or to the head itself such has a hex head bolt. The screw in question would be made of heat-treated steel. The screw would be inserted into a threaded hole but it would be nice to know about a screw that is self tapping.
Currently i mostly use philips head or hex head screws for drywall, wood, metal and plastic (abs). Of coarse my drill starts cam out and occasionally starts to strip my screw. Recently i used a square holed screw and the bit was so secure that the drill started to twist violently. This was not something i was used to as iv mostly used philips. So i was wondering based on the material strength what hole size would be optimal for high torque situation?
Best Answer
I would say the optimal screw hole shape that will allow the maximum amount of torque to be applied, would be no hole.
Removing material from the head of the screw; no matter what shape, will weaken the screw slightly. The only way to maintain the full strength of the screw; and therefore achieve maximum torque, is to not remove any material. So a hex head screw (not to be confused with a hex drive screw), would allow for maximum torque.