To hold the centerline on the workpiece will help the device shown in the figure.
Recommend to read
An all-purpose vehicle for a farmer
I built the self-propelled chassis called “Bychok” (Little Bull) more than ten years ago. Over this substantial period of use the machine has proved unpretentious, reliable and capable....
Candle-impromptu
It took a long warm-up fine detail, but what? Matches? Do not impossible to satiate, and uncomfortable, and the candle was not at hand. Rescued, as always in such cases, the savvy....