QTR-Quadtone RIP

Same thoughts here.  Sometimes it is hard to see the test pattern.

 

Elliot

 

From: QuadtoneRIP@yahoogroups.com [mailto:QuadtoneRIP@yahoogroups.com] 
Sent: Sunday, November 09, 2014 9:46 AM
To: QuadtoneRIP@yahoogroups.com
Subject: Re: [QuadtoneRIP] Convert K3 to K5 - problems: R3000 not printing
low black dilutions ???

 

  

I'm using piezography K7 inks for B&W-only on my R3000, so I can speak only
to part of your post.  In the pz mode, the yellow channel is the lightest.
When I do a nozzle check, it appears that nothing is printed from the yellow
channel. However, if I print a full page of the yellow channel from the ink
separation file, it is obvious that that channel is working fine because
there is a only slight difference between paper white and "yellow."

 

Give it a try before you go on to a fix that may not be necessary.

 

HFL

 

 

 

From: "amog19@... [QuadtoneRIP]" <QuadtoneRIP@yahoogroups.com>
Reply-To: <QuadtoneRIP@yahoogroups.com>
Date: Sunday, November 9, 2014 at 9:20 AM
To: <QuadtoneRIP@yahoogroups.com>
Subject: [QuadtoneRIP] Convert K3 to K5 - problems: R3000 not printing low
black dilutions ???

 

  

Hi Everybody,

 

I have a situation with my R3000 not printing low black dilutions - at least
this is what it looks like.

 

As described in my earlier posts I want to turn an R3000 to a dedicated b/w
printer. For that I started making experience with the tools and skills
needed, as QTR, colorimeter, inks etc.

 

So far I was able to use QTR to create optimized curves for the specific
paper and ink combination I currently use on the R3000. Besides QTR I use MS
Excel and SpyderPrint for fine tuning curves. The results are encouraging so
far. Based on the feedback I got here and reading through further ink
recepees and blog posts I dropped my initial idea to turn the R3000 to a K5
printer. I decided to only replace Yellow with an additional shade of grey
to preserve full toning capability between warm and cool blacks. I do not
need Yellow since I don't need sepia-type tones. In conclusion I want to go
for K4 with 3%, 10%, and 40% besides 100% black. Normal and light magenta
respectively cyan remain for full tone control in the lights and shadows.
(Roy, Paul, David: I appreciate your feedback, I think you brought me on the
right track)

 

With MIS pigment black and MIS P. Roark formulated clear base for 1.5 pl
printers I created the 3%, 10% and 40% dilutions. 10% and 40% are making no
problems, they are printed as expected.

Only the 3% black is not printed - and I cannot tell why. This is how I
proceeded: I made sure to propperly flush the yellow channel (air, water,
windex, water, aqua dest, air) before priming that channel with 12ml of that
3% ink. To my knowledge the printer's ink channel takes about 10ml each to
be filled. After priming and attaching the filled cartridge I cleaned the
print head's sponge base and the head itself (paper towel, windex) from
excess ink.

When I do a nozzle check (after a cleaning cycle) or print a color purge
file, the paper remains untouched where the yellow channel would print. Why?

To check if I maybe had broken the yellow channel (broken / perforated hose
/ joints) with excessive pressure from flushing (20ml syringe connected
tightly with flexible tube to cartridge connector, slowly moving the piston
1mm by 1mm) I carefully applied the same flushing, priming and outfitting
procedure to the magenta channel - with the same result: no print out / ink
coming from that channel head.

In my opinion, the completely empty paper (where those channel heads should
have printed) indicates that this is not a clogged print head. Since I
primed each channel by pumping about 12ml ink each channel should be filled
to its head with ink (indicated with excess black ink on head and head
sponge base), so it should not be an empty head either. Also the cartridges
seem ok. I used two different cartridges and made sure that the ink
connector and the air hole are unobstructed,  otherwise preventing the ink
to move through the print head.
My approach to prime / charge a channel with ink seems not to be wrong:
after failing on those two channels with 3% black, I reverted on the magenta
channel to magenta ink - and the printer prints on that channel fine again.

 

How should I interpret this behavior? Does the R3000 head not "move" inks
that consist of 97% clear base? Is the clear base the wrong one?

 

Right now it looks like I wasted a lot of ink and time - without getting
where I wanted. Do you guys have an idea / any related experience that can
help me understand? Is there a specific challenge with low-percentage black
dilutions? Is it an accident that my specific problem ( I broke something?)
shows up with the 3% ink? When I don't get this fixed I will sadly go back
to the original ink configuration and hope the printer has not suffered .

 

Best Regards,
Amin