Ball setting vise

[ps_bond]

Most of them have a screw to stop them rotating, but if you're considering thumping something then the larger balls are more resistant. I wouldn't use a small one for hammer & chisel work, for example (standard engineer's vice on a post, walk around it is easier)
My usual way of working is one hand manipulating the vice, other hand has the graver/micromotor/hammer handpiece/whatever.

[Petal]

So, if I'm using a hand pusher type, I'd still need to hold the ball with one hand and push with the other, as only having one screw to stop them rotating is not enough, surely?

[ps_bond]

The brake is there to stop it or slow it rotating - so if you're engraving straight lines, for example. You'd still hold the ball though.

[Petal]

OK, many thanks for that Peter.