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Joanna Carter
22-Aug-2009, 10:45
Hi folks

Having just gone through one or two of the most harrowing days of my photographic life...

I have an Epson R2400 printer with a Fotospeed Quill CIS attached. The inks are superb, the printing results wonderful. That is, until the other day.

I had noticed that the auto test pattern for the nozzle check/clean routine was producing a slight difference in density across the light magenta and light cyan patches. Anyway, I needed to profile a new paper and set about it, using the Spyder3Print, but I started to get all sorts of problems of profiles that gave me horrible magenta casts on a subsequent print.

To cut a long story short, I found that the problem lay in the fact that the ink in the CIS reservoirs had started to separate out and I was obviously pulling a more dilute light magenta ink when printing the test target, thus fooling the profiling software into thinking that I needed more magenta to balance the colours, only to realise that the thicker ink started to come through after the test target had been printed, to give the next print that "warm" look :rolleyes:

So, I set about emptying the reservoirs, emptying the ink from the lines by using a syringe on the cartridge, and remixing all the inks in their respective bottles before refilling the reservoirs, bleeding the lines through the cartridges, etc. The result; a much denser colour patch on the nozzle check/clean pattern and the ability to get a good profile once more (phew!!)

I gather this can be a problem, not only for CIS systems but, also, for printers like the 3800 and up, where the ink is not shaken by the movement of the heads.

Three questions :

Has anyone else had this kind of problem?

Does anyone know of a way to keep the inks from separating?

If separation is inevitable over time, how can I easily remix the colours every so often to ensure I don't have to go through the hassle of bleeding/refilling the whole system?

ric_kb
22-Aug-2009, 12:16
to keep the "inks" in solution I "swirl" the containers regularly (at least weekly). I swirl by moving the rig I have my inks in in a circular motion on the table. I don't pick them up, just move around them across the surface. Big particles fall out quicker than small particles.

Tyler Boley
22-Aug-2009, 13:47
agitating the carts is normal maintenance procedure for many of us, particularly with larger carts. Weekly is fine, maybe every two. Higher quality inks stay in suspension better than lower quality inks, it's part of the formulation to address this. Even so, any ink will settle out given enough time.
Tyler
http://www.custom-digital.com/