Branko,
As a professional mechanic I use a Var Cotter press. However it can be done with a less expensive C-clamp than the Var version of a C-clamp. I am not saying a hammer is the option best offered, but the expensive tools are actually versions of old tools. A good machinist can use a drill press to do the work that most use a milling machine for. The best cotter presses are just versions of C-clamps designed for specific pressure points. Just my experience. Smiles, MH