I also purchased the HF Airbrush and was using the same 50/50 mix as you were, Bariqua. I was also running the mix through a pair of my wife's stockings. The air brush was spitting then clogged. I then purchased the Neo TRN-2 pistol grip airbrush, `what a difference, it has a much larger nozzle. No clogging, it gives a nice even coat.I'am still using the HF compressor on 20 or 30, works great.
I have the Fiebings book of Top Finishes, it has Tan-Kote, mix with water if using a sprayer. It doesn't mention how much water. It does say that you can mix a small amount of dye with the Tan-Kote and water. I haven't tried it yet.It says, you can mix Bag Kote with up to 20 % water. I used it and it worked fine. The Acrylic Resolene seems to be thinner with the 50/50 water mix then the Bag-Kote.I do love the way the air brush workes with dyes, comes out great.
Jim