Aargh! The End Has Fallen Off. Again

Years ago I bought a vice that I have used a lot since. Unfortunately it came with a handle that has two round ends pressed on it:

 The problem with the handle is that the ends have a habit of falling off:

 After an end fell off for about the fifth time I finally got fed up enough to build another handle. The first attempt using some 12mm bolts failed as the material is just too nasty when machining it. You can just about turn the outside down, but drilling and tapping is impossible.  I used one of the chair legs that I chopped up with my bolt cutters to make a new handle:

The ends are turned aluminium held on with M6 cap head screws. If they fall off I can put them back on easily, and maybe use thread lock. So far so good, and it looks better too.