The quality of processing lumber a plane largely depends on the sharpness of the blade of the knife (or as it is called, is the glands). And because sharpened part is always from the body of the plane, when storing it is easy to damage. To protect the blade, it is possible to close the removable rubber ring.
Recommend to read
PARACHUTE IN THE SKY
This motor glider (currently, such devices are often referred to paraleli), developed in the design office of the club of Amateur technical creativity "Evrika" Yakut posely Torgo, called...
MISSILE FOR A NUCLEAR WARHEAD
R-5M - the first in the world military equipment of the booster of the nuclear charge. Her starting weight was 28.6 tons, flight range is 1,200 km. Developed in 1954 - 1956, OKB-1 headed...