How NOT to fail with the German Refilling method

[ThrillaMozilla]

I have completed your drawing, see below. I added the ink outlet, and if there was a POOL of ink, it would come out of the outlet as well, but it is prevented of doing so by the lack of air above the ink in the ink chamber.

You're correct that it works 100% of the time for most people. I'm simply telling you that if you drill the hole above the opening, it cannot leak in normal use, but if you drill it lower, it might under some circumstances. As I say, continue what you're doing, but if someone experiences a leak, you'll know what could cause it.

I'm trying to put this diplomatically. I do know how to calculate pressures in a hydrostatic system, and I've even read the Canon patent on the subject. I gave you a physical model, which admittedly is a little simplified by putting the sponge away from the walls, in order to avoid having to explain the concepts of hydrostatic potential and capillary potential. EDIT: It's even simpler than that. Let's just say that if there is any leakage path through, under, or around the sponge, it will leak out if the hole is under the water line.

Now to answer Redbrickman's and your messages. Yes, it could leak out the bottom if there were a hole in the ink chamber, because you have up to 3 or 4 cm of head. But no, because the ink chamber is intact, even without the sponge it might not leak from the exit port, because you have only a few millimeters of head. Remember that you have to overcome the capillary action of the filter (and as you have drawn it, the sponge). So no, I don't think your diagram is correct. We can't be sure without knowing the capillary properties of the filter (and the sponge would certainly prevent the leak).

The vacuum in the ink chamber controls the level of ink in the sponge chamber, but it won't keep ink from coming out from a hole. The capillary action of the sponge and the filter is what does that--not the vacuum in the other chamber. To see this in action, poke a hole in a hummingbird feeder. Or just do a thought experiment. Put a sponge in there to stop it if you want.

Write what you want, but please, I don't want to discuss this any more. I've spent too much time on this.

 

[The Hat]

This thread has being going now for a while and going nowhere at all I reckon.
What I can see is that everybody is arguing over this simple 7 point dos and donts plan made out by panos.
It was just his way of refilling that worked for him and he taught rightly so,
that it should work for lots of people, its not a bible.

I was surprised by some of the critics getting on their high horse saying
this was wrong and that was wrong, No thats not the way I do it.

All agreed is not perfect but is works that's the point that panos was just trying to share with us.
If someone followed his method after their own refilling was not going exactly to their liking would that be so wrong.

I taught that suggesting ways to adjust or improve ones refilling methods would be welcomed but then I have being wrong before.
I think everybody should lighten up and put away their slide rules and calculators
this was not meant be the Ten Commandments just a few simple guides guys.
Happy Refilling and lots more printing..

 

[slocumeddie]

Hey......The Hat.....RIGHT ON !!!
If I recall correctly, "The angle of the dangle = the heat of the meat, but only if the mass of the _ _ _ remains constant"

 

[websnail]

Regarding the "very low" needle issue... A couple of points that may not have been realised.

1. By drilling at the bottom and then prodding away with the needle you may lift the sponge slightly and as a result remove the sponges "protective" presence from the hole allowing ink an easier path out.

2. A lifted sponge may also result in the exit hole sponge being separated from the lower full width sponge section and cause ink starvation.


And just to note on the subject of "rules"... There's always exceptions and like when we learn to drive, we adhere to the rules until we have built up experience and know that sometimes rules need bending or ignoring.

The tight adherence to literalism tends to get seriously bent out of proportion on here sometimes to the point that hair splitting requires an electron microscope to spot the point... Perhaps a little lattitude eh?

Case in point, tape... Aluminium tape will prevent a leak IF the refill point is clean and dry before the tape is stuck on. Most "regular" tape won't.


*puts on the flame proof suit and prepares for battle*

 

[gigigogu]

First time I saw this topic I said to myself: Oh, no, not another German method topic.

But then, after evaluating panos guidelines and replies, I had an idea: what it would be to think at German method not as a compact, indivisible thing, but as a combination of parameters/variables, each with two or more values. Each value has a positive or negative influence for one or more stages, and overall success or failure is the result of particular combination and not because of single variable.

The stages are:
1. During refill - failures: ink going above sponge and into air maze, ink leaking out along the needle
2. Long term storage- failures: leaking, evaporation
3. During use - failures: ink starvation, leaking

Parameters:
a. hole placement - values: near bottom, at distance from bottom
b. needle - values: blunt, sharp, thin, thick
c. seal on hole - values: no seal, adhesive tape, hot glue
d. cartridge empty before refill - values: yes, no
e. topping - values: yes, no
f. saturating upper sponge - values: yes, no

Most combinations are neutral with parameters balancing each other, or with limited impact in only one stage, but:
- The worst combination I think it is: a. near bottom, b. blunt and thick, c. no seal, d. no, e. yes, f. yes, can result in a full mess, in all stages.
- On the other side, the combination: a. at distance from bottom, b. sharp and thin, c. hot glue, d. yes, e. no, f. no, is a winner.

 

[panos]

@gigigogu, I think that users would continue to report problems under the generic "german" or "durchstich" method which is why I made this post in the first place. Also, I believe that modified versions exist in a particular combination of elements which may affect others. So it's difficult to produce such a table.

Perhaps, however, it would be interesting to suggest to Pharmacist to update the official description of the method to include the various modifications at a new section with a disclaimer that some of these modifications may provide a sub-optimal experience.

 

[rodbam]

Have people reported problems with the German method that wasn't user error? The problems I reported with the German method were through my incompetence & since then I've had a trouble free run refilling with this method.
I made my refill hole as close to the bottom as possible because I didn't want to pierce the sponge but I'm getting worried about now after reading this thread.

 

[ThrillaMozilla]

I don't know, Rodbam. From what I've seen on this forum, so many people report success the way you are doing it, that I don't think anyone would want to raise an alarm and convince you to change your procedure. Besides, if you switch, it might be inviting a new problem. Who knows?

 

[websnail]

I remember a book... Think it was "The Intruders" that had a list of rules... The one that springs to mind is:

If it's dumb and it works, it ain't dumb!

Makes sense to me...

 

[ghwellsjr]

As I said in post #15, I not only violated most of these rules, I encouraged others to do so also. I even broke some rules that weren't stated here by Panos but should have been in my opinion. But there were reasons why I broke the rules.

The original announcement of the German method by Defcon2k was in 2006. Almost a year later, pharmacist put together his excellent post on the German method with pictures. Almost two years after that, pharmacist put together another post including pictures of opaque cartridges with windows in the reservoir. It was at this time that I started to use the German method and I thought from the pictures on this last thread that it was appropriate to make the refill hole as close to the bottom of the cartridge as possible. I stated this on post #12. I may have also gotten the idea from post #78 of pharmacist's first thread:

The best way is to go under the sponge, but it not harmful if you are piercing through the sponge substance.

Later on in this same thread on post #139 I asked pharmacist:

I make the hole as close to the bottom of the cartridge as possible, just above the thickness of the plastic. My blunt needle slides very easily under the sponge along the top of the bottom piece of the plastic cartridge. Why would you try to pierce the sponge material? Am I doing it wrong? I thought this was the way you were supposed to do it.

And he responded:

ghwellsjr,

you are doing right: but sometimes it is inevitable to encounter sponge material and then the trick is not the press the sponge together, but to pierce through it (the hole is quickly sealed by surrounding sponge material filling up the cavity, so you will not experience any problems). I try to avoid sponge material as much as possible, but sometimes no luck...

So this deviation from the original statement of the German method started me off on the wrong track because with blunt needles, it is difficult to get the tip of the needle over the lip at the entrance of the reservoir hole so if rotating the needle wouldn't get it in, I would flex the needle down and up in order to get the tip over that lip. Well this enlarged the grove in the sponge that you get with the needle going along its underside. I was aware of this potential problem and so I believed it would create a problem with air flowing directly from the refill hole to the outlet port which is only a short distance away. I expressed my concern in post #41 of the second thread:

I recommend sealing the German refill hole to prevent two potential problems:

First, leaving the hole unsealed allows the daily fluctuations in ambient air pressure to gradually dry out the water in the ink and make it more concentrated.

Second, leaving the hole unsealed can interrupt the normal air flow in the cartridge resulting in an ink flow problem. The air normally flows through the air vent above the sponge compartment down through the upper sponge to the groves that go half way up the wall separating the two compartments and into the hole at the bottom of that wall to replace the ink in the reservoir that is drawn out of the cartridge. Instead, as the print head attempts to suck more ink out of the cartridge, it just gets air.

You don't need a seal as good as the one you would need for refilling at the top of the cartridge, just a small piece of flexible tape will do.

I was not the least bit concerned about a leak because if there were any possibility of a leak, it would be more likely to go out the outlet port and we know that doesn't happen.

However, I made another mistake and this even shows in my second video on German refilling. I re-used the same piece of tape to seal the refill hole. The problem is that ink gets on the adhesive and essentially renders the tape useless and, as panos pointed in post #21 on this thread, it may have even provided a priming path for the ink to leak out. In any case, what I did was not good. What I should have done was remove the old tape, clean off the area around the refill hole and apply a new piece of tape.

So now to test the idea of making the refill hole higher up, I did that and had no trouble pushing a blunt 20 gauge needle through the sponge material where it hit the bottom of the cartridge between the outlet port and the entrance to the reservoir. But try as I might, I could not get the needle into the reservoir. And now I can see why you must use a sharp needle because a simple rotation gets the point of the needle over the lip.

Now I have become convinced, as has been expressed on this thread earlier, that having the hole higher up so that the path of the needle does not go between the sponge and filter on the outlet port, eliminates the problem of the air path from the refill hole to the outlet port so my major concern about sealing the refill hole evaporates. My other concern having to do with the ink drying out is only a factor if you don't refill your cartridges often, say in three months. And as has been pointed out earlier in this thread, having the hole up higher probably eliminates the potential for an ink leak out of the refill hole.

So where does this leave us? I think we need one more rule stated, especially since it is in the original announcement of the German method: use a sharp needle and I personally think it should be 20 gauge.

I've already outlined my concerns about some of the other rules since they aren't in the original announcement but a sharp needle and a small hole above the bottom of the cartridge are the most important.