A good method for finishing FDM 3d printed patterns

I will fork the discussion of my part back to its thread:
https://forums.thehomefoundry.org/index.php?threads/pattern-rapping-fail-sailboat-part.2268/page-3
Thanks again to @Rocketman for the links and the pics of the great work on his patterns/parts.

 

Tops, try a different airbrush? It took a little adjusting to get mine to lay material down nicely, I tested on some cardboard first to get a feel for it.

I just eyeballed my acetone/spot putty mixture, not sure where it ended up at in ratio.
I did note that too much air was letting the mix dry before hitting the pattern - perhaps this is why you're getting dust that wipes off yours?

My HF airbrush states to run at 30psi.

Once adjusted, if I hit one area too hard, it would pool up enough to begin to run ever so slightly. That seemed to be the sweet spot for application.

 

Airbrushes are designed to use VERY thin paint with finely ground pigment. They aren't meant to lay down a lot of material quickly.
You need to use something like a touch-up gun, might even be called a spot repair gun. They use a little more air than an airbrush, but they'll handle your spot putty mix a lot better.

Plus you'll be able to adjust your fan pattern, and your fluid flow rates easier. Horrible Fright has them and here's an example from Amazon: https://www.amazon.com/Composite-Detail-Sprayer-Filtering-Protective/dp/B07KPX7R6Z?th=1

Don