I have brush-painted several fins, cones, and transitions with thinned dope.
The key is using thin MANY coats with a wide (at least 3/8") flat brush.
Never tried to do tubes.

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When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, TURMOIL, FIASCOS, and HAVOC !