HP88 black printheads : Feedback please

[websnail]

This is really for anyone who has or has had a printer that uses the HP88 printheads. I am particularly interested in experiences with the B&Y (Black and yellow) type as this is the one that's been causing me no end of problems in a number of printers.

I've been using Image Specialists inks in tandem with a number of different printers with these heads and so far I'm unable to tie down a specific issue... In desperation and as something of an experiment I've opted to try putting in:
- OCP black ink
- a Dyebase equivalent

At present this is just in a K5400 printer and at the moment I can't say it's overly scientific as the printhead has been the same for both and displaying the dreaded ink starvation issue (ie: banding early on in printing).

For a while now I've believed it's related to air bubbles getting into the printhead and there's plenty to indicate that this is one cause of problems, but I'm now starting to think that the problem also involves ambient temperature and air humidity as well.

In one particular school I've had 3 different K550 printers that showed banding issues in less than 4 days from a new printhead being installed and this has a major heat issue with 30+ PC's on in the room and air conditioning that regularly stops working. This was the worst example... Other schools have had varied experiences but another school has had a couple of L7780's start banding quite quickly before failing completely after less than a few weeks, and yet their environment is quite cool, no direct sunlight, etc...


So, I'm trying to identify if anyone else has had any experiences with these printers, be it OEM inks only, CIS from china, refillable carts... whatever... and just give a detailed description of how you maintain the printer, provide ink supply and what sort of behaviour you get out of it over X prints and/or Y period. It'd all be useful.

Thanks..

 

[jimwejimwe]

I have currently running 2-K5400 and 2-L7680
Yes I also have had problems with Black/Yellow head. Back when I was using K550"s I read that Hp had a problem with these heads. I do think they are better now then the early ones.
Currently I am using refillable cartridges from Inkjetcarts.us and bottom Clips from Macroenter.com.
What I have found to work for me is. I use the refilable clear plastic carts most of the time (much easier to refill) when I notice the slighhtest bit of banding I put in the origanal hp cartridges with the aftermarket bottom clips from macroenter and do a few head cleanings. My thinking is, on the orignal Cartridges there is a black rubber diapharm that I think is a pump of sorts. This is not on the clear refilable carts. with this pump missing on the clear carts it seems the head run out of ink. When the head cleaning is done all that clicking that pump is used to fill the head back up with ink. I have no way of knowing for sure that is what is going on but I do not burn out heads nearly as much as I use to. I also use only Image-specialties ink.


Hope this is some help.

 

[websnail]

hi Jim,

That's of some use but overall what would really assist is just how much you have to change out the printheads (ie: after how much volume of ink). Also any indicators of the environments, temps, etc... you work your printer in..

All useful stuff though and FYI, I ditched the clear plastic refillable carts in favour of remanufactured originals to get the rubber bulb and pump system to work. Why reinvent the wheel right .

Thanks though, it helps a bit... just wish I could get a bit more data on this

 

[websnail]

Right... I finally have a bit more intel from experimentation on a few printers in different environments.

1. The ink isn't the problem, it's the [expletive of choice] printheads.
2. Environment is the key issue
3. HP blatantly know about this and are ignoring the issue in the hope that someone won't put it together.


I've tried HP standard cartridges, OCP and Image Specialists inks in printers in these environments:
- Home attic with no air con, some heat with temps reaching around 30' C approx.
- School IT lab with air con and temps getting to around 35'C at tops.. air con dries things out pretty badly!
- School Corridors with good air circulation and temps max'ing out around 28'C

The critical factor is the air temp it seems, and strangely enough I checked the spec' for these printheads and they are SUPPOSED to be fine in environments of up to 40' C... In a word "[incredulity and yet more expletives]!"... The School IT lab has now seen off four printheads with less than 4 weeks total printing time using ALL of the inks I had available... and just to clarify I did check that I'd pulled through any ink residues from previous inks before putting brand new printheads in. I also made sure the printheads came from different batches.

What I found weird is that the printhead can recover from the overtemp if you leave it long enough and then do a series of purge prints but once you get a printhead with air bubbles in it you really are [variations on expletive unhappiness]... I can't help but wonder if the ink is actually drying into a solid mass in the printhead too... Unfortunately taking a head apart to investigate is difficult as the evidence is likely to be destroyed in the process of opening it.

Either way, I've realised the the black printhead is going to suck like a sucky thing if you use it in hot dry environments...

 

[websnail]

Having had a few of these printers up and running now for over a year I'm now in a position to provide a bit more intel on the HP88 and some solutions I've discovered through experimentation, observation and pure ruddy luck!


1. The environment side of things is definitely a prime cause.
The printers living in cool, corridor conditions are only now showing slight signs of clogging whereas the printers that have been in air conditioned rooms or in classrooms with lots of heating have been showing much more prevelance to clogging and banding.


2. The printers own Printhead cleaning...
...whilst very effective for the dyebase printheads is not overly so with the pigment black head. Instead it tends to clear up some but not all clogging issues and clogs just gets worse over time giving the distinct impression of a dead head.


3. Manual printhead cleaning:
When I first tackled this a year back, I tried a method that has succeeded admirably with Epson and Canon printheads. In essence the approach involves a solvent soaked pad on which the printhead is rested. This should allow the solvent to wick up into the head and breakdown the clog. The actual solvent itself is either an ammoniated solution or a dilute base solution used in the inks themselves.

Unfortunately this approach failed abysmally with the printhead output becoming more and more banded and eventually failing completely after a very short time.

Having examined this further I've come to the conclusion that this is largely caused by the printhead design, in that the system is more or less a self-contained printhead/cartridge which pulls air bubbles into the head as the clog breaks down. My guess (and it is just a guess) is that the pad itself draws the ink out of the printhead thus propogating or increasing the draw of air in to replace it.

Unfortunately because of the design of the HP88 printheads it's nigh on impossible to re-prime them (not that I've tried particularly hard).

3b. Cleaning that works?
However.. I have found a solution which has worked once and which I will be keeping an eye on (ie: trying again) over the next few months.

Instead of putting the solvent on a pad, I've found that one method that works is to place the HP88 printhead upside down on a flat surface (nozzle jets facing up) and then gently drop small droplets of cleaning solution (ammoniated solution/ ink base) on the printhead nozzle surface using a syringe or eye dropper. It only requires a small amount of solution but this goes to work on any clogged ink fairly quickly.

At no point should any absorbant pad or material be used to draw off the excess but the printhead should remain "wet". The printhead then gets replaced and a priming sequence should usually run.

I've done this successfully with an HP88 K/Y printhead out of a K5400 which had a clog starting. The solution was allowed to sit on the printhead nozzle area for about 30 seconds and then it went back in without wiping anything off.. Basically I let the printer handle the cleaning part and it seems to have done the trick.


4. Dyebase Black vs' Pigment Black
Given the fact that the dyebase CMY inks still work perfectly in the environments that the pigment black clogs quickly in, the use of a dyebase alternative is definitely worth considering if your printers local environment fits the bill. The advantages are that the printer doesn't tend to clog but the downside is of course that you get some ink bleed in high coverage printouts and the black is not quite as a sharp.

I'm playing with a dye/pigment mix using ink from the same manufacturer so the base solution should be the same and seeing how that works out. So far it's early days but it may be worth considering to get the best of both worlds... It's very much a YMMV type deal though so proceed with caution.



Hope that update helps and if anyone else tries the cleaning routine suggested in 3b I'd be interested to hear if you find it's a viable approach too.

 

[cnngraphics]

I had the same problem using the clear refillable cartridges.

I thought about one of the replies above and it made sense to me that the clear refillable cartridges do not have the pump found on OEM cartridges. So what happens is, there a "NEGATIVE" pressure build-up inside of the cartridges. You can verify that by removing the "Air plug" close to your ear to hear the "tsoofff!!!".

SO what I do as solution is removing the air plug on each cartridge from time to time and let gravity take care of the rest. So far it's working for me.

 

[websnail]

I thought about one of the replies above and it made sense to me that the clear refillable cartridges do not have the pump found on OEM cartridges. So what happens is, there a "NEGATIVE" pressure build-up inside of the cartridges. You can verify that by removing the "Air plug" close to your ear to hear the "tsoofff!!!".

SO what I do as solution is removing the air plug on each cartridge from time to time and let gravity take care of the rest. So far it's working for me.

Took me a little while to take this on board properly but probably worth noting that air vent plugs (not the fill ones!) ALWAYS need to be removed when the cartridges are installed otherwise you end up with the exact problem you mentioned.

Lack of air flow to replace ink used will always result in ink starvation as a vacuum builds up... A little surprised that this wasn't made clear by the refillable cart supplier to be honest...

 

[cnngraphics]

Took me a little while to take this on board properly but probably worth noting that air vent plugs (not the fill ones!) ALWAYS need to be removed when the cartridges are installed otherwise you end up with the exact problem you mentioned

There is one precaution to take though: if you permanently remove the airier plugs, you will end creating another problem. Remember, inks are made of a volatile liquid combined with pigments. So removing the air plugs permanently will result in coagulation of the ink inside. The key here is to remove the air plugs every once in a while or every morning and put them back. I can do that task instead buying new cartridge..

 

[websnail]

There is one precaution to take though: if you permanently remove the airier plugs, you will end creating another problem. Remember, inks are made of a volatile liquid combined with pigments. So removing the air plugs permanently will result in coagulation of the ink inside. The key here is to remove the air plugs every once in a while or every morning and put them back. I can do that task instead buying new cartridge..

I see your point re: the plugs... they are too wide and allow far too much air flow to dry things out but some form of vent is essential or you end up stressing the printhead... It would seem a little adaptation of the vent hole is required to reduce the diameter to a minimum. I really wouldn't be too keen on leaving the plugs in and having to remember to remove them...

If nothing else this seems to re-affirm my opinion of the HP88 refillable cartridge design... ie: really not suitable..

 

[panos]

websnail, your observations will be valuable to anyone buying an HP inkjet printer.

I made the mistake of getting a printer with this type of cartridges 12 years ago (HP2000C using the No10 ink tanks)

And then again a couple years ago (HP whatever, using the No88 ink tanks)

Both printers cost a lot in both money and peace of mind: OEM ink is very expensive, refilling was a disaster (the HP2000C would also mark tanks as forever empty once the plunger pushed all the way into the ink bladder), the ink tanks had an expiration date and the printers themselves despite their "pro" look are not on par with the Canon quality (eg. regular misfeeds in both models and extremely noisy).

A refillable cartridge would fix a lot of issues but as you describe it, it's not an option either...