These are all valid concerns, and I'm happy to throw my 2¢ in, if it helps. I've been printing for a while now, (FDM, MSLA) and even went semi-pro for several years (9 printers, 40+ hrs/wk), but still take this with a grain of salt, of course. Every use case is unique, and there are a wide variety of products and methods out there, so don't be afraid to experiment to find what works best for your project. 🫡

That said, I've had better than average success with Rust-Oleum spray varnishes for all but the most demanding/complicated projects. Be patient (don't rush), keep the coats thin/light, always use PPE & proper ventilation (no joke), and test print whenever you feel the need to try a new tech/process out.

So, first off:

1. What's the PLA model going to be used for?
2. How durable does the varnish itself need to be for the intended use of said model?
3. Are there moving parts that need to be masked before spraying so the clear coat doesn't gum up from friction?
4. Indoor or outdoor use? (ie. Avg temps, weather, etc.)

🖖🏽🤓