vicious cycle (Mutoh Faclon Outdoor 48) ink priming and nozzle loss

vicious cycle (Mutoh Falcon Outdoor 48) ink priming and nozzle loss

Does anyone have a solution for the following Mutoh issue(s)? Any help would be much appreciated! I've been working these issues for the past 2 months, reading and working through many of the basic steps found here at sings101.

Problem: Repeatedly losing and re-obtaining nozzles. After priming the system from the new dampers and also the maintenance station waste tubes most of the nozzles return. The heads were adjusted while attempting to align them. Most of the nozzles, then, vanished. Priming left head through waste tubes worked. Right side remains stuck (ie no ink flow, syringe plunger will not pull any ink through the maintenance station.) Cleaning cycles provide no improvement.

Given:
-New Eco-Ultra CMYKLcLm solvent ink (type that causes sponges to exapand)
-replaced waste tubes
-disassembled peristaltic pump. Tubes appeared functional. Black ink spot was found on tube inside of pump, next to cam which will cause a different catastrophe in near future.
-cleaned matenance station caps and tubing.

Possible Suspects:
-pump cam position maybe stopping ink flow to waste station.
-ink flow may be stopped at a port in the maintenance station cap.
-original ink flow restrictions caused at ink cartridge pins (no error messages, though)
-pushing maintenance station to far right detent position to allow ink flow from heads into caps does not release the right head. (mechanisms for this are unknown!!)
-Mutoh Gremlins who live and operate in the motherboard containment area. Head Rank Gremlin may also exist.

 

After speaking with the Mutoh service dept (AZ), who was very helpful/knowledgeable, I found a few more clues...

1) While executing a 'charge' command, push the heads over maintenance station to the far right detent (as if manually priming from the waste tube end) and listen for a change of pitch from the pumps which would indicate a bad seal. (I do not remember seeing a 'charge' command in the menu, but there should be similar to push ink to the heads in a test mode without moving them.) My issue 'no flow', but this may help someone who is losing nozzles.

2) Since the problem started after trying to align the heads, the heads may be seated in the cursor assembly incorrectly. They seemed to be seated correctly, but there may be other issues there.

Does anyone have any other ideas or insight into this? Thanks

 

'Solvosclerosis' seems to return 2 or 3 days. I took the pump and maintenance station apart and cleared the tubes with solvent. The tubes were clogged. A tube could be collapsed.

After clearing the tubes, my step was to align the heads. The mounting screws on the heads were loosened and rotated with and w/out the front levers, then, tightened down again. That's when nozzels were lost, again.

The left head can be cleared through the waste tubes, but not the right head which would reamins stationary. I'm thinking that the right head is not in the tray(cursor) properly or the base of the head gets flexed/twisted. Thanks

 

It sounds like you saved alot of money by avoiding a new pump, maintenance station, and tubes.

I heard the same issue about the wiper arm which gets jammed up with ink within a plastic channel. The wiper may not go back and forth and the finger that drives it sometimes breaks off.

It seems like primming the tubes through the maintenance station might cause excess forces on the tubes and whatever else. The alternative is a strong cleaning which wastes ink.

When I cleaned everything I did not see any broken parts.

TUBES: while researching which tubes could be used on that pump, thnical support at Labware and Specialty Plastics Thermo Fisher Scientific
was very informative and helpful. "In general I’d recommend something fluorinated (PFA, FEP or similar) for resistance to most solvents- although I was able to find that ordinary polypropylene or polyethylene is acceptable for use with at least a few of the ethylene glycol-ether varieties on the ink MSDS.
The limiting factor, I expect, would be something flexible enough to work with the peristaltic pump. Best of luck- drop me a line if you need anything else!"
[tygon and teflon may be too rigid to use]

They did not have the part, but referred me to Saint-Gobain Performance Plastics. However, Saint-Gobain was difficult to communicate with and I could not find the product.

 

Understood. It makes the most sense. As 1 cam rotates in/engages the other rotates out/disengages. I'll double check it within the next week or so.

Thanks for the suggestion.

 

The fingers were not broken. I attached some photos which show some of the components.

From the attached views, I have a few questions and made a few assumptions.

1) Both left and right pump side cam sets need to be somewhat in sync. It looked like one set was engaging when the other was disengaging.

2) Once assembled the hose can be snugged up against the cams by pulling each side of the hose or does it matter if there is a gap? The roller cam has to push the fluid through, so, if the hose rests on the outside perimeter does it still engage well enough?

3) The dark blue spots on both sides of the hose seem to indicate that ink might be starting to bleed through the hose unless it is created from the outside. They exist in a location where the ink pressure increases during the cycle.

4) Other- The nub on the wiper track and the white, flat plastic part controls the back and forth motion of the wiper. I found this area to be full of ink which could jam things up.


Thanks

 

It does not appear to be losing fluid through cracks or anything. I'll have to find a replacement tube anyways. Does the gap of the tubing about the cams have little impact?

I'm in the stage of isolating and pressurizing each tubing section. It might be a problem at the capping station or at the heads.

Thanks for the suggestions.