To work poster pens are very convenient, and who was fine — what makes them miracles: you can always pick up the desired width of the line, replacing the pen on the right more. But each can hold only one “track”. But this small improvement allows us to obtain two parallel lines… in a single pass. For this, needle files propisyvaetsya portion of the working edge of the Pera: are formed like two pens in one.
Recommend to read
“BABY” PAVES THE FURROW
From the family of microstructures developed by students of Kharkiv Institute of mechanization and electrification of agriculture, the easiest and most accessible for self-production -...
TIMER WITH KNOW-HOW
Most radio Amateurs, unfortunately, do not publish their devices. Although sometimes their design is novelty, which still has not invented and did not. In the magazine "Radio" in may...
