To cut a Sonotube:
Measure how long your Sonotube needs to be and mark the point where you should cut.
If you are cutting with a handsaw or any hand-held cutting tool, wrap a wide paper with a clean straight edge around the Sonotube. This paper will act as a straight edge so you can draw a perfect circle around the tube.
Carefully follow the line you drew around the tube as you saw.
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