Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@y..., "Paul Roark" <
paul.roark@v...> wrote:
> Bob,
> 
> The inconsistencies of the Piezo ink may relate to the use of a CIS.  If
> that is the case, it might be a good idea to take some ink from the 7000
> carts I got for you and see what they look like.  Those users are probably
> going to be the most critical of any density differences any way.  Is it
> possible to pull a couple of ounces out of the carts for testing?
> 
> Paul


Apparently the inconsistencies may have been caused by the CIS 
cartridges slowly unseating themselves which allows air to enter 
through the base feeds of the ink stems which the cartridges rest on. 
Manny from IJM called me to give me the heads up on a fix which is 
curing quite a few users. You push the CIS carts down and make certain 
that you push them down frequently.

I had the DDS syndrom which is when your prints lose density in the 3/4 
tones. That is the ink which is mostly affected by the cart rising. But 
Manny suggested a fix earlier which was to bypass the CIS cartridges 
completely and run the tubing directly onto the ink stems. That was an 
instant cure and I am still using that after about 3 months and have no 
plans to return to the CIS system.

I actually am running another Piezo system on a 1200 printer and 
started it off by drilling holes in the bottle tops, running tubing I 
bought at a hobby shop which is secured in the middle of my printer 
with a loose tie-strap attached with foam tape. The trick is to raise 
the printer about 2 inches higher than the bottles to make up for the 
lack of restriction caused by all the twists in the CIS cartridges.

My suggestion to users of bulk ink systems is that DDS may occur in any 
of these ink systems after maybe as little as 6 months use. I would 
suggest people thinking of getting into a CIS or a CFS to save the $150 
and make your own rig. I do not mean to be a consummer watchdog, but it 
will save you a lot of money and aggrevation.

DDS in Piezo is when one of the inks prints at lower pressure. It is 
usually the position which makes up the 3/4 tone. The images begin 
printing lighter and lighter in the shadows. With Piezo inks this will 
make the results appear green. What I began to do was make my prints 
darker and darker until I couldn't compensate any more and began 
pulling my hair out and cursing Bill Bergh. My cure was to use the 
direct tubing. I didn't change out the inks for MIS.

If you want to see if you have a DDS on Piezo or MIS or any Quad inks. 
Take an image you first printed when you set up your CIS. It has to be 
one which you have saved or archived. If you print it again after about 
6 months maybe less or more, and it prints lighter, then you may have a 
DDS. You need to press your CIS cartridges firmly down to make certain 
that they are seated and this will allow full pressure of the inks 
again. 

I think it would be interesting to see if there are any cases of MIS 
DDS. I am uncertain if they have been bulk fed as long as the Piezo 
inks which have been supplied with the CIS for more than 2 years. So 
maybe users which have been using a CIS for 6 months or more could try 
my test. I will report back to the Piezo list. There aren't many MIS 
users on the Piezo list and this list seems to be more MIS oriented.

Pete