In the holes drilled in a wooden tube in the concrete wall, there is always a lot of sand and dust. To remove them will help plastic or metal tube by simply inserting it into the hole and how to blow into it (but mind your eyes!).
S. DOROFEEV, p. vokhtoga, Vologda region.
Recommend to read
TERMINAL SQUARE
Most automatic screw machines have trehkanatnoy the self-centering, which is easy to fix the workpiece cylindrical or hexagonal shape. And if it is of square section! In this case, a...
FIND “THE FOX”
In the early 30-ies of the radio Amateurs of the Soviet Union, mastering of ultrashort waves, for the first time faced the necessity of direction finding of radio transmitters. The...
