Digital BW, The Print

You could try the procedure 9 - MAJOR CLOG from HELL (Fantastik/Windex 
Treatment) found on http://www.piezography.com/ts/faq.html under point 
3. Clogging issues. I recommend removing the whole printer cover. Only 
four screws.
.
> Had posted a question earlier that I was not getting a good head 
> check on the yellow position of my 1280 using Piezotone WN inks. Just 
> printed a 21 step gray scale and the first 30% is all white no steps. 
> I believe that I have a clog or they didn't load up the shade of gray 
> that goes where the yellow head would spray. Since I have cleaned 
> heads 20+ times what should I do? 
> 
> Any help would be appreciated.
> 
> Thanks,
> 
> Barry