7800 purge one channel studioprint

I am currently running Piezography Selenium ink in a 7800 using Studioprint. I have determined that the light cyan channel containing Selenium shade 3, third from the left, is having a problem with banding. I am sure it’s this channel. I can create a Studioprint environment selecting only this channel to use as a purge to clean this channel. What solid value would I assign in a tiff purge file to print through this environment?

Use the inkseparation image in calibration mode. Bring the 100% patch of the affected channel to cover the entire image by selecting and transforming it - and save as that channel purge. Print it using calibration mode according to the directions for your OS. Then only that print head will print… takes a few sheets to replace an ink this way… It could clean out your head unless you have a clogged damper that needs replacing…

Thanks Jon. Is your answer based on Studioprint? It seems to be based on QTR

Yes, QTR because it’s easier to use for the purpose of maintenance in your case.

In StudioPrint you would have to make a new linearization based solely upon the affected channel. Turn all the others to <none>. Make the affected channel the <Black>. You could edit the linearization table by hand. Drop in 1.3 across all the values. Then make a black image and print it.

However, I do not recommend purging by printing as a cleaning method. It’s not. You have to apply the suction of a POWER CLEAN or INITIAL CHARGE. You have a 7800 and Power Cleans are available. Just use the Power Clean twice to bring PiezoFlush to the print head. Turn it off 24 - 48 hours. Run normal clean cycles until clear. It will waste ink in the other channels. But, it is effective.

Banding however, is usually a dirty damper - especially if the nozzle check is good. Sometimes PiezoFlush will not clear that even after 48 hours. We change dampers on about an annual basis as a preventative maintenance. Hard the first time - and then about an hour or less each time after.

Thanks Jon. I will change the damper. Probably the whole set.

You should always replace all the dampers at the same time (unless you had a new/defective one). Dampers should be replaced every 1-3 years for the best ink flow and function of your printer. Get the repair manual for instructions to replace the dampers. We always get printer manuals from www.2manuals.com, but you can get them other places online as well.

Best regards~ Dana :slight_smile: