Which black ink damages the Epson ink switch valve?

[martin0reg]

I don't want to print without both K's because on glossy MK is unusable, rubbs off..
and on matte paper (almost all "fine art" papers) PK doesn't reach the black of MK, the 1000-dollar-printer with weaker black than a 100 dollar printer??
If one more nozzle row was no option (for whatever reasons) they should have done it without LLK, I think that's the "color" we would miss least, looking at the prints.
But then again some say, the LLK would make a better gloss, acting like a GO.. I don't know..

 

[Ink stained Fingers]

on glossy MK is unusable, rubbs off..

about every matte ink rubs off on glossy papers including a Durabrite black to my experience,
the driver does not even select the black ink when a glossy paper is selected in the driver.
The other question is whether a matte ink even rubs off on matte papers of various types, I'm aware of such
complaints with an Epson printer, and a GO overprint does not fix that.
And it could be interesting how Canon printers/inks perform in this respect.
Or it may be worth a test with a mix of PK and MK on matte paper to get a better black level than with PK only
and still some better rub resistance.

 

[martin0reg]

Yes, I have read about rumors that in MK ink there may be small amount of "Photo" ink ..
But I can't tell the difference truely: MK ink has biggger particles than PK ink - but we are talking about "pigment" ink here, and these pigment inks generally have bigger color particles or molecules than dye ink...
If the bigger (pigment) MK particles make deeper black on matte paper than the smaller (pigment) PK particles -
- why are dye inks, with the smallest particles or molecule, as good on glossy as on matte paper? I have often compared the brilliance and black level of dye and pigment on glossy and matte - and dye is better in both aspects: better gloss on glossy and better or at least the same black level on matte paper! With dye K vs pigment MK! Pigment PK on matte paper is visible weaker than dye on matte. So the reason couldn't be the size of (pigment) MK and PK particles alone... what is it that MK for pigment on matte is needed for deep blacks, but this is not the case with dye?

 

[Ink stained Fingers]

I think we are discussing here just some assumptions - why should matte lack pigments be bigger than photoblack ones for which Epson and other suppliers claim some type of encapsulation, and why should such photoblacks - encapuslated - perform pretty bad on matte papers ? An how would a Piezography black perform in comparison - an even better black ?

 

[W. Fisher]

Cone sells a MK and PK that are advertised as blacker than the OEM Epson black inks. https://shop.inkjetmall.com/About-ConeColor-PRO-High-Density-Blacks/

Don't know if they are more resistant to clogging up the MK/PK valve though.

W.F.

 

[martin0reg]

Some assumptions are more evident than others.
"PK is not as black as MK on matte paper":
- you can see it. Some people more some less... but in my experience it's worth the second black
- it is the only reason for offering such "matte" black for pigment printers.
"MK has bigger particles than PK"
- you can see this too, when you hold a strong light behind the ink bottle (e.g. canon text black)
" Dye in general has smaller particles than pigment ink in general"
- I'm no chemist, but you can read this often, the difference seem to be big, because it's a different kind of solution, much less prone to settlle down.

 

[Ink stained Fingers]

Cone sells a MK and PK that are advertised as blacker than the OEM Epson black inks.

Yes, but not by much, you can measure it, but I question that you would see a difference in actual prints.
There are several effects to consider when looking to matt vs. glossy papers - the directional or diffuse reflection of light and the absorption of light.
Dye ink molecules are floating around in the solvent, pigment ink is in this sense not a solution but a collodial suspension which requires addtional efforts to keep the pigments afloat and apart.

 

[Alan G]

As one whose 3880 just suffered the ink valve failure this past weekend I can tell you that either ink can cause the valve problem. I had been printing mainly with MK the past four months and when I attempted to switch to PK to profile a new paper it failed to properly switch. One knows this by seeing blobs of black ink on the right side of the page as it comes through the printer and in my case the yellow channel was discolored with black ink and there was also a problematic nozzle check. I tried a couple of switches to see if that would clear the problem and it did not. The printer is 8.5 years old so it has passed the Epson 5 year point that is mentioned in the service manual. I thought about DIY repair and one can purchase Epson parts and get a "pirate" service manual. However, the ink supply and capping station assemblies (both should be replaced if one is going to do this) will be in the neighborhood of $300. I watched a couple of videos and this kind of project is doable but Epson do not make it an easy one since a number of parts have to be removed to get at the two assemblies. If you put a new ink supply assembly in it has to be filled and that would have required me to get more ink. In addition, I have no idea what the state of the print head might be which is a further cost if that needed to be replaced. In the end the opportunity cost to repair this was too great.

I think the 3880 was one of the best printers Epson ever manufactured. I never had a blocked nozzle during all the printing I did and it could stand idle for a considerable period of time and then just print away. IMO, the ink switch valve is the Achilles heel of this printer and an engineering design flaw. Perhaps the Epson engineers felt that this was the best way to go given the print head design. I had to decide on whether to replace this with an Epson P800 or a Canon Pro-1000. I decided on the Canon.

 

[JayDecker]

Alan - had the same problem with a 3880 and just finished replacing the ink system, capping station and air pump. The cost was $275 for parts and about two-days of time. Installed new a piezography b&w ink in the printer and it is up and running perfectly. The printhead condition was a nagging question as the work was performed, but worked perfectly. Don't know if this story will be of help to you, but thought you might appreciate one happy ending story...

 

[Alan G]

@JayDecker - If I had enough room, I would have done exactly the same rebuild that you did. Kudos to you for persevering.