Caring for inkjet heads was filmscanners: real value?

[Arthur Entlich <artistic@ampsc.com>]

I apologize for continuing this off topic thread, but anyone who is 
following it probably has some interest, and I've change the subject 
line for those who are not so they may ignore it.

Over the years, I've leaned a few things about Epson ink carts that 
might help others to avoid some problems.  The reason the non-chipped 
ink carts are not supposed to be removed or reused is because sometimes 
airlocks develop.  The piezo crystals in the heads do not create a large 
enough draw or suction to pull an airlock out of the ink delivery 
system.  (More on this later)

The new carts with the chip have been designed to block the ink delivery 
holes in the cart, and the ink posts in the printer at removal so the 
systems both stay relatively sealed after removal, to prevent both 
airlocks and drying out.  Epson might have also improved the ink 
cleaning station to seal the heads better to prevent drying on that side.

Epson's non "intellichip" ink carts are sealed at the factory 
de-aerated.  Since most fluids at normal barometric pressure have 
dissolved air in them, and Epson knew that an air lock can easily 
develop in the ink supply system when a cart is removed, Epson figured 
out that if the air was deaerated when it was packaged and sealed into 
the cart (probably by either heating or vacuum packing) that the 
deaerated ink could re-absorb the air from the airlock once it was 
opened (during the cart exchange) and installed.  This ability only 
lasts a few hours at best.  After that, since the cart is open to air 
through the vents at the top, the air re-dissolves into the ink.

That is why Epson suggests not removing a partially filled cart or 
re-installing it.  However, I have to admit, I have done so on many 
occasions.  Now, I also admit I have early Epsons' which had much more 
industrial strength vacuum pumps built into them for ink cleaning and 
purging, so what I state here might not hold up for the newer wimplier 
models.  Whenever I reinstall a cart, i test it.  If I get 
non-performance from one or more noozles/colors, I do a few ink cleaning
cycles, but before doing so, I place some water or my "cart-clean mix" 
on the cleaning station to help create a better seal and vacuum to help 
the system draw the air lock and ink out of the head. I have yet to have 
an air lock that was not resolved within 2-3 cleanings.

Your mileage may vary.

Art


Laurie Solomon wrote:

> It ( the HP) may not have clogged up in part due to the fact that HP's
> typically have their nozzles in the cartridge itself; whereas Epsons and
> some other brands do not.  In the pre-chipped Epson printers there was a
> reservoir of ink between the cartridge and the nozzle which could dry out
> and harden as well as the ink left within the nozzles which could dry out
> and harden.  With the intro of the chipped cartridge in the 1270, this is
> less likely to happen.  However, before the advent of the chipped cartridge,
> it was recommended that one not remove the cartridges from the printer
> except to change them when they were empty for that very reason.
> Unfortunately, even the OEM cartridges in the older printers, if left
> standing for an extended period of time without being used would tend to
> have air leaks that would cause the ink to dry out sometimes at the outlet
> from the cartridge but more typically at the nozzle.
> 
> As for how to flush the nozzles, I believe Art has already suggested one
> way.  I suppose there are other ways as well that one could get from the
> Epson Inkjet lists or from some of the third party ink distributors.
> Personally, I have not run into the problem myself; but I suspect that I
> will soon be facing a clogged old Photo Stylus which has been sitting unused
> for 1 year with the ink cartridges still in it and which I did not take my
> own advice to you.
> 
> Oh yes, one other thing, after you have removed the partially used ink
> cartridges from the earlier model Epson printers, do not try and reinstall
> them later.  Use a new fresh set of cartridges.
> 
> -----Original Message-----
> From: owner-filmscanners@halftone.co.uk
> [mailto:owner-filmscanners@halftone.co.uk]On Behalf Of Hart or Mary Jo
> Corbett
> Sent: Wednesday, January 31, 2001 12:23 AM
> To: filmscanners@halftone.co.uk
> Subject: Re: filmscanners: real value?
> 
> 
> Laurie:
> 
> Thanks for the reply.  How would one flush the ink out of a printer?  I
> thought they didn't operate if a partially used cartridge was removed.
> 
> Certainly, my ancient HP DeskJet 870Cxi won't run if even the cover is
> opened but it's so old that it's a museum piece.  BTW, it has never clogged
> or dried up though, even when we've been away for two months.  Res is awful,
> longevity worse, color a nightmare.
> 
> Hart Corbett
> 
> ----------
> 
>> From: "Laurie Solomon" <laurie@advancenet.net>
>> To: <filmscanners@halftone.co.uk>
>> Subject: RE: filmscanners:  real value?
>> Date: Tue, Jan 30, 2001, 7:54 PM
>> 
> 
> 
>>> (1)  Will the 1200, using non-OEM inks, clog up if it's used for periods
>>> separated by months?
>> 
>>> (2) Will the 1200 clog up, using Epson inks, if only used periodically as
>>> above?
>> 
>> In an attempt to respond to the above question, I think that most inkjets,
>> including the 1200, if left for any extended period of time could clog up
>> with either OEM or third party inks.  With non-OEM inks, there is always
> 
> the
> 
>> distinct possibility of clogging due to other factors such as air bubbles
> 
> or
> 
>> impurities.  Clogging due to extended periods of inactivity ( especially
>> with respect to third party inks) can be minimized by flushing the ink out
>> of the printer.
>> 
>> 
>> -----Original Message-----
>> From: owner-filmscanners@halftone.co.uk
>> [mailto:owner-filmscanners@halftone.co.uk]On Behalf Of Hart or Mary Jo
>> Corbett
>> Sent: Tuesday, January 30, 2001 3:58 AM
>> To: filmscanners@halftone.co.uk
>> Subject: Re: filmscanners: real value?
>> 
>> 
>> Michael:
>> 
>> Thanks for your excellent advice (and the opportunity to post this
> 
> message).
> 
>> ..SNIP....
>> 
>>