Cast in many industrial products have long been used mortgages (anchor) bolts with special heads, such that not only pull, but rotate can’t.
With the advent of high strength composite self-hardening compositions that bolt you can “lay” in the body of the finished product (plastic or metal) and making it pre-nest, and then simonaityte.
Recommend to read
THE GYRO ON A ROPE
Model autogyro designed and built in the laboratory of the Aero modeling club of young technicians of the Siberian branch of the USSR. The author is a graduate of the class of technical...
ITALIAN SUBMARINE “MOSQUITOES”
"Dwarf" submarine or midget submarines occupy a special place in the underwater shipbuilding. Of them, in fact, grew large submarines with a displacement of tens of thousands of tons...