To hold the centerline on the workpiece will help the device shown in the figure.
Recommend to read
MOPED IN THE HANDS OF A CRAFTSMAN
The owner of a light moped (or, according to modern classification — a mo-vel, that is, a motorized bicycle), equipped with a D-8 engine, eventually notices that their two-wheeled machine...
FUNNY FIGURES
It is widely known attraction of children to animals: any child would be pleased with the appearance of new cat toys or dog. To make a figure with their hands—it is easy. ...
