sp300v ink starvation whilst printing crop marks

[Steve Purdon]

Hi all, really hoping someone can help, i’ve been fighting some issues with my old sp300v for a few weeks now, i’ve recently replaced all the dampers, cap tops and the magenta/yellow head, however i’ve now got an issue where its failing to print the crop marks, it tries but doesnt lay down enough ink to print them fully, it then however goes on to print the design perfectly, and then fails at the second set of marks too, i’ve printed out some black/cyan/magenta/yellow colour blocks and printed them at different head speeds, as the speed gets up past 700mm/s it starts to fail printing the black and cyan, at 1000mm/s it barely prints them at all just like the crop marks. There’s plenty of ink in the dampers, and interestingly if i remove them and re seat them it starts to print the marks again, but by the time i gets to the second set of marks it fails again. so i’m pretty sure its a starvation/supply issue, however i’m stumped as to what can be causing it?

the dampers and cap tops are all new and OEM ones, i’ve tried doing cleaning cycles, medium cleans, pulling ink through manually from the cap top, manual cleans, i’ve had the dampers off and replaced with the old ones, tried priming the dampers with more or less ink. nothing seems to have any effect other than for a short time. at normal print speed of 4-500 mm/s it prints perfectly, however i need to laminate a couple of the jobs i have lined up and its making it impossible!

does anyone have even the faintest idea or suggestion?

is there any way at all to slow down the crop mark printing?

thanks a lot!

steve

[Kevin Mahoney]

Have you tried cleaning the encoder strip? It doesn’t sound like a head or damper issue if the print is good, same with the dampers. I’m no engineer at all so I would be calling one soon if cleaning the encoder strip doesn’t work

[Steve Purdon]

Hi kevin, thanks for your reply, yes i did try that and no difference i’m afraid!

i wondered if the small holes on the nipple of the damper were possibly blocked up slightly and causing the lack of ink, swapped it out a spare and still no better, i gave up and swapped the heads side to side as a last resort and the issue has followed the head, the black and cyan will now print perfect at high speed and the mag/yellow are struggling, so i can at least print the crop marks again and the mag/yellow head is printing well enough at slow speeds to at least get the job done. still no better idea why its failing at the high speeds but if it starts to fail more i’ll have to swap it out for a new head.

[Myriam Garrido]

Sounds like it could be a pump issue not drawing enough ink through or there’s a blockage or air leak on that side. Worth checking the cap seats properly and the hoses to the pump are clear. Can’t remember if there’s only 1 pump for your printer or 2

[Chris Wool]

possibly a cracked manifold on that head not uncommon after changing dampers as they do get a little brittle with age . there is also micro filters in the head