Black not printing after standing

[Andysam26467]

Hi all,
i have a strange issue.
i have two SG400 and one SG800 printers.
i use genuine Sawgrass ink and Trupix paper.

the black stops printing when the printer has been standing for around 1 hour. It starts printing again half way through the print and then continues to print fine until it stands for about an hour. If it has been standing for longer (say overnight) it prints fine. It only happens if it stands for about an hour.

if I do a clean on the black head before I print (after it has stood for an hour) it’s fine.

ive cleaned the heads and the capping stations.
The strange thing is it happens to all 3 printers. I’ve changed ink cartridges.

they are a couple of years old and are used a lot. I think one is on about 30,000 prints.

is it they have just worn out?

just thought I would ask before I replace them

cheers

Andy

[John G]

Maybe a computer or lead fault rather than all 3 printers