Date:         Tue, 01 Oct 91 11:30:49 +0100
From: Karl Pottie <GHGAQA0%BLEKUL11.BITNET@forsythe.stanford.edu>
Subject:      deskwriter cartridge refill



This text describes how to refill your Deskwriter or DeskJet ink cartridges.
It is a summary of experiences by different people. This text has been
posted to the mac archives before, but it was deleted. I repost this
article on multiple request.

1) Why to refill your cartridges ?
----------------------------------

Deskwriter cartridges are pretty expensive. But there is a quick and easy
way to refill your cartridges yourself

2) Why not to refill your cartridges ?
--------------------------------------

So far I have never heard of anybody damaging his deskwriter by refilling
cartridges. But HP doesn't recommend it.
Also, the new HP ink is more 'water proof' than any kind of refill. So if
need more or less waterproof print-out, you'll need to stick to HP.

3) When to refill ?
-------------------

As soon as you notice your cartridge is running dry (printout becomes faint,
lines are missing ...) you should refill your cartridge. It's better not
to let the cartridge run completely dry, and you should certainly not let
an empty cartridge sit on a shelf for some time before you refill. Some
people systematically add ink to their cartridges to ensure it never runs
dry.

4) How many times can your refill ?
-----------------------------------

After a number of refills, the printing nozzles become blocked by dirt and
the refill will not longer work. Usually you can expect about 3 to 5 refills.
I've been told that the thermal-pulse resistors in the jet
mechanisms will tend to wear out after 5 refills or so... this will lead
to dots that don't print.  [If you run the printer self-test, the
printer controller runs a test-pattern, and will actually print the jet
number of any jet-resistor that's not drawing the appropriate amount of
current... so you can tell the difference between a clog, and a jet
problem such as a burned-out resistor or a dirty contact pad.]


5) Which ink to use ?
---------------------

Sheaffers's Skrip Jet Black ink seems to please most people. Alternative:
Park Quinck Permanent Black.But any water-soluable ink should do.
NEVER ever use india ink, because this uses solid suspended particles which
almost immediately clog up the nozzles.
Print-out is generally a bit less sharp than original HP ink, because the ink
spreads out more. It also takes a bit longer to dry. Smuding is worse
than the new HP ink.

6) How to refill ?
------------------

* always remove the cartridge from the printer
* be sure to place some cloth on the surface where you refill , in case of
  leakage.
* get a syringe with a needle of about 4cm long.
* fill the syringe with about 10cc of ink (less if you refill systematically).
* the cartridge contains a sponge ink reservoir.Insert the syringe into the air
  hole on top of the cartridge (in the green arrow) You should make sure the
  needle penetrates the sponge as deep as possible (about 4 cm).Make sure
  you do not block the air-hole completely.
  Do not try to refill by just injecting some ink on top of the sponge. You
  should always penetrate the sponge !!!! All difficulties experienced
  while refilling seem to originate from trying to let the ink
  soak in from above.
* SLOWLY fill the cartridge. If ink starts leaking, stop filling.
* put cartridge back into printer and run the priming cycle.

7) Professional refill kits
---------------------------

Some companies offer professional refill kits. Usually these are a kind
of accordian-like syringe with an injection tube of the correct length
which contain enough ink for one refill. These refills are usually quite
expensive, and the question remains if the ink they contain is any better
than fountain pen ink.
You could buy a professional kit once, and use the empty kit
to refill the cartridges with fountain pen ink.This way you always inject
the right amount of ink, at the right 'depth'.


8) miscellaneous notes
----------------------
   Hewlett Packard recommends that the ink cartridges NOT be
   recharged for the following reasons:
1.  Fountain pen ink dries with a crust, clogging up the jets.  This
    would obviously result in erratic performance.  This crusting
    will also contribute to a clogging of the priming tube.  Without
    a properly functioning priming tube, the cartridge's jets will not
    have the opportunity to clear themselves prior to a print job,
    resulting in erratic operation.  [note that the Hewlett Packard
    ink also crusts...also, the alleged special ink from HP is not
    available for purchase]
2.  The clogging will also leave deposits on the special "wipe"
    platform which cleans the cartridge as it travels across.
3.  More than likely, DeskJets found with these deposits will have
    voided warranties.

I have been told by a fellow netter that some ink manufacturers
incorporate cyanide into their ink.  I presume that this is done
to inhibit microbial growth so as to improve the shelf life of
the product.  Given that the DeskWriter cartridge mechanism works
essentially as an atomizer, the possibility exists that the
cyanide concentration in a small enclosed room could reach poten-
tially dangerous levels.  Therefore, one should be most cautious
when selecting the type of waterproof ink for re-inking these
cartridges.  I strongly recommend that you call the ink manufac-
turer to find out if they use cyanide in their ink preparation.
If not, you should at least ventilate the room in which the
printing is done.


Thanks to everybody who helped me collect this info !!!

Karl Pottie