The sonotube (actually some other brand - perhaps handi-tube?) I always
end up with won't peel at all.  I use a wire brush on an electric drill
to seriously roughen up the inside of the tube.  Gives an extremely black
surface when spray painted flat black.
The outside of the tube I fill the spiral grooves then sand smooth and
paint many coats of gloss paint sanding lightly every second or third coat.

Richard
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: The sonotube (actually some other brand - perhaps handi-tube?) I always
: end up with won't peel at all.  I use a wire brush on an electric drill

In California there is Sonotube (perhaps another brand) available with no
wax coat on the outside. The inside wax peels off very easily.  I also
fill the outside spiral groove and then paint with a gloss *plastic*
paint.  Winds up looking like a plastic OTA.

take it for what its worth ...

-Robert
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