A simple clamp can be made from a long bolt, washers and nuts-lamb. The jaw faces are made of solid wood.
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UNIVERSAL INDICATOR
Two LEDs with different color (e.g., red and green), you can build a simple indicator for voltages from 4.5 to 220 V. It is also able to determine the polarity of the source in the range...
WIDE OF TWO
Broad brush painting is quicker. And if one is not at hand? In this case, it will help out the spark of two narrow. If the workload is small — they can simply attach sideways to each...