Mutoh Jr. issues

[ahollow]

Here's the problem. I replaced the heads, pump and capping station. Just before doing so, I printed a test pattern as a record of how bad the heads were. The black and color heads printed, but not all nozzles.

So I replaced everything, waited 30 minutes after the fill as per the instructions, and did a test print. Color was fine, but no black (K). Checked everything; it looked fine, so tried another test print. Still no black. So I sent my test file (the alphabet with every letter a different CMYK and RGB color). The file printed fine, including the A (which is set as K, as well as BCD (CMY) and all the rest). So I tried some more test files with different colors, just K, etc and it works great.
Now, I tried to print a contour cut project, and no align marks. Yet the black image printed fine, and the printer went through the motions of printing the align marks.
So for some reason the printer will not print internal commands for black (K), or system-generated align marks, but no problems from a file. Strange, huh?
I'm making my own align marks and it's working fine, but it adds a few minutes to each job, and I need to send separate cut and print files, which I never had to do before.

So, just wondering if anyone had any thoughts? Maybe I changed a setting in the Diags or something?

Thanks for taking the time to read through this, and any comments you may have.

 

[sfr table hockey]

I may not be totally right here but I think you can have a black color printed by using the colors mixed from the color head so you might not be getting that black color printed from the black head where as the crop marks might be 100% black from the black head.

If you put in a new black head (not sure if your unit has black on its own) but did you change the head rank in the printer? Next you will need to draw some ink into the head to pre fill it and then several reg cleanings to get it to fire right. Use a syringe to draw from the cap for the black head.

 

[randya]

What does the nozzle check look like?

 

[ahollow]

sfr - The K cart is printing; I did many test files where the object is set as 100% K, nothing else. The ink does flow through both heads on a cleaning, I've checked that also.

Randya - the nozzle check looks like a regular nozzle check, minus any K. No text prints, just the color bars and lines.

Thanks.

 

[J Hill Designs]

make sure your RIP isn't changing that 100%K value to something else internally (such as 67/69/63/62 or whatever)

 

[ahollow]

OK, good thought. Although looking at the dots with a magnifying glass, they all look grey (no CMY in there).

I wonder if it's safe to disconnect the CMY head cable, then run another test, just to verify that the K is actually printing.

 

[J Hill Designs]

prob will throw an error - but you can set up a pure K file (vector) and tell the RIP to do no color correction, or you can (maybe) set it to print greyscale only (Flexi prod mgr you can)

 

[P Wagner]

If the internal, firmware-based nozzle check pattern is not firing K ink, that you can rest assured that any files from the RIP are not.

That is the point of the nozzle test print, to isolate the printer from other factors.

 

[randya]

Castek is right, if the printer is not printing k, there is no way for the RIP to.

Is there K ink in the damper?
If not:
power off the printer

recheck all your head cables

Search the forum for head fuse and check the k fuse.

My guess is that you dont have the k head cable in properly, if you are lucky, you just blew the fuse.

 

[ahollow]

OK, thanks everyone. This is why Signs101 is such a great place. I searched on the "head fuse" and will pick up a few holders and fast-blow 2A fuses this afternoon. I'll check the fuses for continuity, and replce the blown fuse (with power unplugged, of course.)

I'll let you all know how it goes, thanks.

PS: I just saw the notice on the head boxes. It says to turn off the power switch, unp[lug the power cord, then turn the power switch back on for 5 minutes to drain the power supply. then turn off the switch and do the repairs. If we are all not following that, that may be why we are blowing fuses, even with the power off.

Thanks again!