Missing Channels

[102RCR]

VJ 1624, All of a sudden one black channel and one magenta channel are completely gone. Replaced complete maintenance station, dampers, encoders, and print head. getting the exact same result and it was before changing anything.

Anyone have any ideas??

 

[Solventinkjet]

Do you see any air bubbles in the ink line above the dampers? Did you change the o-rings when you changed the dampers?

 

[102RCR]

No air, and yes, after replacing did an initial ink charge.

 

[rjssigns]

Check the cables. Doesn't take much to make a print head act up.

 

[Solventinkjet]

No air, and yes, after replacing did an initial ink charge.

I would do a damper swap to isolate the issue. Switch the dampers position and then run a cleaning cycle and then see what prints in the nozzle check. If the same colors don't printer in different positions, something above the head is clogged or malfunctioning. If the same channels don't fire with different colors in them, it could be a main board issue.

 

[102RCR]

Check the cables. Doesn't take much to make a print head act up.

The ones from the board to the head are new, will double check the others to see if I can see anything.

 

[102RCR]

I would do a damper swap to isolate the issue. Switch the dampers position and then run a cleaning cycle and then see what prints in the nozzle check. If the same colors don't printer in different positions, something above the head is clogged or malfunctioning. If the same channels don't fire with different colors in them, it could be a main board issue.

Can you explain that more? Isn't that just checking that the dampers are working?

 

[Solventinkjet]

Can you explain that more? Isn't that just checking that the dampers are working?

You want to switch the damper positions on the head, not the tubes that go into the dampers. That way you are trying to print different colors through different channels. So if black is next to a cyan and you switch the damper positions on the head, they should switch in the nozzle check. Basically, you want to see if another color will print through the channels you are having issues with. You already know the yellow and cyan are working fine so if they don't work in the channel you are having issues with, that tells us the head is incapable of firing that channel for some reason.. And vice versa, if the magenta that isn't firing works fine in another channel, that tells us that it's not an ink flow issue in the magenta and most likely electrical.