Digital BW, The Print

I have tried to get the hang of black only printing as described by 
Clayton Jones so well.But, when I try this with my Canon S750 
printer; I fail to get any values above Zone 7 to have any body in 
them. They are all blank white. I have tried increasing the 
intensity of the black ink from within the printer properties 
without success at all. I even went to transfer setting and adjusted 
the curve in the direction I thought would give me the desired 
results, without any avail. I indicated to the printer it was to 
print in grayscale mode and had assigned Dot Gain 30% with 
Photoshop.I was using Quadtone printing very well till I read about 
this which would seem to save a bundle of cash from not having to 
buy color cartridges every two weeks. That will break a rich man 
soon. What am I obviously doing wrong????? Back to Best Buy tomorrow 
for more ink to experiment with. I must have made 30 prints today 
trying to get it right.