Digital BW, The Print

Excellent experimenting and detective work there, it is good to 
share this stuff to lead to a better understanding of what is going 
on...

My recent observations with a ten week old CFS on an 1280 with VM ink 
are not over yet and I'm waiting another day or two before drawing 
conclusions. I am waiting for ink to dry on a sample I printed 
tonight. It is starting to look like I did indeed have something 
altered in the k ink bottle with the CFS after only 10 weeks- but I 
can't confirm that for another day or two. I do know that if there was 
a change, it was just beginning to happen, and was still very subtle. 
It wouldn't be recognised by a glance at a print. One would have to 
have a stepwedge recently printed and compare it side by side in a 
good light to a sample printed months ago to see the change at 100%k.

So I can easily imagine that I could have left the CFS go for quite 
awhile longer before it really became visually noticable on prints and 
I encounterd the clogging degree that you describe. And my environment 
is arid so perhaps that may also account for time difference of ten 
weeks vs 1 1/2 years.

I remember that with an 1160 and a CIS using the old piezo (Sundance) 
inks, I was one of the discovers and namers of DSS or "the greenies". 
I didn't notice a "density shift" until the CIS had been operational 
for about six months. Now I see that Jon Cone does not reccommend 
using a CIS with the old inks due to evaporation.

It would be ironic if I indeed can confirm there are evaporation 
problems with my CFS and VM ink after only ten weeks of use in my 
climate. Of course there are a lot of "ifs' and "buts" dealing with my 
climate and printer to printer variation I can't account for 
precisely...
Jim H.

--- In DigitalBlackandWhiteThePrint@y..., Peter McLennan <peter@v...> 
wrote:
> I found that my CIS lasted about a year and a half before the black 
channel 
> quit.  I had poor black channel performance and tried many ways to 
clear 
> the "clog", including injecting the head directly with Windex.   
When I got 
> a good test pattern, I ran a black-only test image at high speed and 
> watched as the ink lay-down quickly went from total black to just a 
few 
> black lines on the page.  I deduced from this that it was the CIS 
that was 
> starving the black head for ink, not a clogged head. I bought a new 
CIS, 
> installed it and I'm printing normally again.  Others have commented 
that 
> the black channel (not the head) suffers from clogging due to 
evaporation 
> of the solvent through the Nalgene tubing.
> 
> 
> regards,
> 
> Peter