Digital BW, The Print

I just loaded an Epson 1200 with Piezzotone Carbon Pigment inkset and ALL THE NOZZLES 
ARE  CLEAR and the printer works great but I'm getting a posterized ( non-linearized) 
image in the midtones and dark midtones.

I did not buy the custom profiles for this printer but have tried the 1280 profies I bought 
for another printer. Color files print almost indentical on these two printers, but not these 
mono inks.  I don't have a grand for every printer I want to try. I'm planning to use three of 
these with different inksets an three different printers. Several canned profiles were tried 
and I also printed a 21 step greyscale and hand made my own curves to straighted out the 
muddy lack of sepeation. The grey scale looks normal now to my eye with this curve. But 
no go, still posterizing with an image file. 

Do you guys think that I could use QTR with this set up, or "hand design" a profile of my 
own without a densitometer? They don't have to be perfet, just close.

Thanks,

John