Q: I have a request for a titanium socket head cap screw. The customer asked to have this screw made to DIN specifications but I found two DIN specs for a socket head cap screw. What is the difference between DIN 6912 and 912?
A: A titanium DIN 6912 socket head cap screw is never fully threaded because the pilot recess is a deep hole which goes from the head into the screw and much deeper than the head is height. If you would roll on or press on the thread, the pressure would be too high in this area and the head would break off. Whereas on a Titanium screw per DIN 912, does not have a reduced shank, the pilot hole is not as deep and therefore the full thread is much closer to the head.