Jim- I've never sprayed latex with my 400, but I have used it for shooting epoxy primer. The only tip I've ever had was the medium. No problems at all. As far as adjustments, I would spray a test pattern with water onto paper or cardboard. That way you can adjust fan pattern and the needle. Adjust your compressor for about 30, 40 PSI. Badger 400 is an excellent gun and user friendly. Jim