SP-300 Print Problem

[Huskysteev]

Hello
I am new this forum so not 100% sure how things work yet.
Anyway my Roland sp-300 has some print issues, the solids starts
to fade when the heads are running accross the vinyl, its solid
towards the head park but becomes faint as though its a different
colour all together as it passes about half way.
I have changed all the dampers and head cleaned using the machine
head clean (powefull) and the manual clean with the correct liquid and
head cleaning swatches.
it appears to be running out of Ink about half way but then it prints correct colour
all the way down on the right hand side of the machine.
this is a sample i did today it printed out the other way round
the darker correct colour is the head park side of the machine, any you guys have any ideas.
many thanks.
Steve H

 

[niksagkram]

I'm thinking it might be electrical in nature. Maybe one of the cables to the head carriage is loose and as it moves across the printer your heads are firing incorrectly.

Mark

 

[Solventinkjet]

I have seen this happen a few times on other brands of machines that use the same heads.

More Likely:

I would double check the dampers first. If you see any air bubbles at all, even a very tiny one, in the ink lines, you have an air leak and that is most likely causing the issue. The damper should be about half full. If it is completely full, it could still work properly but it could also be a sign of a malfunction. If it is much lower than half full, there is an air leak / failing damper somewhere and is most likely causing the issue. Also, especially on older machines, the o-ring that is located between the ink line and damper can pinch the ink line and cause ink flow issues. Check the ink line with the o-ring off. If the line has a very noticeable divot in it, cut that part off and re-install the damper. It sounds primitive but I have done it at least 25 times with good results.

Less likely but I have seen it happen:

I had a customer with the same exact issue and it ended up being the manifold was clogged like an artery. The ink slowly built up on the walls of the manifold and choked the ink flow. By the time the head made it half way across, the ink flow couldn't keep up with the demand and dropped out but then came back during the pause between passes. I took the manifold off and replaced it with a new one which fixed the issue. You could try flushing the head too but changing the manifold is what I recommend.