To hold the centerline on the workpiece will help the device shown in the figure.
Recommend to read
“MERCEDES” ON THE ASPHALT AND OFF-ROAD
All-wheel drive MERCEDES-Benz ML-class. We have somehow got used to whizzing through the streets of the city to the jeep, which, in fact, are not vehicles, but only cars-"overgrown"....
THE SU-26M, SKY ACROBAT
At any exhibition there are always centers of attraction of attention of visitors. There was a and in the Central exhibition NTTM-87: it was — as, indeed, in all previous aviation...