Do I have a problem with dry sponges

mikling

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OK

sit down and the fans of the German method, don' t take offense.

First Grandad35 mention of surface energy is spot on. The forces in liquid are actually a lot larger than we normally acknowledge. That is key. We need to think at the micro level and this will admittedly be difficult to those not trained in sciences. So it is easy for misinterpretations to occur.

The final picture in the set shows something that at the beginning of this thread but no one chose to comment or even repsond. That indicated that like politics, if there is a difficult question that defies answering..ignore it. What it showed is a a lockup condition of a cartridge that could occur.

In the CLi-8 Canon chose to introduce a groove that leads from the reservoir to the bottom of the sponge. Over the years some incluing me mentioned that this was a difference. Indeed some aftermarket cartridges also had it as well. German method refillers love this groove as it helps guide that needle into the reservoir.

The purpose of the groove is to ensure that there is a continuous body of liquid ink from the tank to the sponge. This allows the "surface energy" or surface tension to be reliably set up. So as the ink is removed from the bottom sponge, ink is PULLED out of the tank to replenish it. The network of close proximity fibers in the lower sponge sets up a very strong surface energy network, Strong enough to pull ink out of the tank. Try to understand that. It behaves like it is elastic. So it is not the head pressure, that allows ink to flow out but the surface tension aspects. There is negative pressure within the tank BUT the overriding force or effect is surface tension. That outlet hole is also sized to have this effect. You can imagine if I cut the hole exiting the reservoir, the liquid will leak out and it will. The hole is actually designed to be withing a certain size.

Now why did Canon add this groove over the years. The first answer I postulate is that it would improve the functionality of the cartridge. Yes, that is reasonable or else theywould not have done and continue to. This is where we need to keep calm. Canon likely experienced the situation I showed in my final picture where the sponge was not drawing ink out of the tank. The i"nk bridge" I will call it that, was broken. Once the ink bridge is broken, ink receded back into the tank and the ink within the sponge would get consumed and the tank would still show itself to be full of ink. That ink bridge will answer many questions as to why some cartridges do not feed properly.

Now let's take a look at the ink bridge. The bridge would be stronger or the liquid link to the tank would be stronger if the surface contact to the tank is larger. That is why Canon opened up the groove. By doing so, the allowed for a column on ink that joins the tank to the bottom of the sponge. Now it appears that some third party mfrs also caught onto this. Well some copied the bridge but I don't know if they knew why. However some did not make the bridge but rather created a sponge with a tail that entered into the reservoir. This ensured continuity of the elastic ink from the bottom of the tank to the sponge.

Npw I will address the German refill method. I think many of you would now figure out why sometimes it fails under certain conditions. You can fill the reservoir like I showed in the pic BUT if the ink bridge is not reestablished or the column of ink is not put back in, there is the potential for a lockup.
Why? because after the needle is withdrawn, there is less volume in the tank, the ink body recedes a bit and when the body of the cartridge is turned back right side up, the ink within the tank will not come out and the ink bridge is not established. Now this happens under certain conditions and I believe ghswellsjr might have run into this and others. I am not surprised. Why because he is likely so exacting and neat in his process he did not overfill the tank thus causing the condition. Now if you overfill the reservoir a bit, you are less likely to encounter this. That is the reason why you need to continue to inject ink as you withdraw. It reforms the bidge. However, if the lower sponge is really empty then this may still fail at times. If you refill at the first warning, then it is not likely to be an issue as there is sufficient ink in the sponge to prevent the sponge from grabbing the liquid ink bridge. If you look under the cartridge, just make sure that the ink continues across to the sponge. Alternatively, you can withdraw the needle to the point where it is just at the separation wall, turn the cartridge back right side up, inject about 0.1-0.2cc and this will reestablish the bridge.

Now with the top fill method, the bridge is at the bottom and liquid flows down. The bridge is never broken during refill. So top filling removes this issue completely.

At the start of this thread irvweiner said the opened the plug and that allowed the ink to flow again. In doing so, he reestablished the bridge as in a top fill refill.

So there, it is not as some may have interpreted that I am against German refills, and cause some hate to run within their veins but rather I can see some issues that could take a lot of explaining to show. These issues are never present with the top fill. Some of the issues against top fill that are promulgated by the advocates of german refill methods have shown to be incorrect and false.

You can refill ANY way you want, it's a free world in some parts but just be aware of what you are doing and take the steps to make sure it is correct.

My last comment on the German refilling. ...When I grew up I always admired german autos and their engineering and their great suspension systems ( not electronics) and I held german engineering in very high regard ( I was trained as an engineer). I am not so sure that this convenient refill method deserves the german title really as it introduces a potential problem that had been overlooked or not explained prior to this. Trigger37 should chip in on this thread as he would be thrilled.

Now again it is not that I don't advocate the German method, Heck I sell a lot of syringes and 2"needles solely for this method, and I would not do that unless it worked. But just do it properly.

Now that you understand what role surface energy plays, surface tension, then the wqrds like capillary, meniscus and Epson's Active Meniscus Control. All have some meaning now. BTW, I am still in awe of Epson's Active meniscus control. Imagine a cup of water, that you drop something into. There will be ripples. What if you now flex the sides of the cup so that the ripples are counteracted and the waves settle out quickly. That is the concept of Active Meniscus Control in the wide format nozzles.

This thread should now pose some other questions as to why the sponges are not filled all the way etc. But knowing what you now, the questiion about the size of the newer cartridges should come up as well. Just how much smaller is the "real" capacity of these newer cartridges. I know there had been a strong reaction but was it really warranted?
You see Epson, using their mini ciss systems on their printers was making their printers flatter. Canon had to make theirs flat as well. So.....chop off some height.

And Canon does fill via the top fill for obvious reasons. This is the Japanese refill method. But there still exists the Canon method which I will keep for a while.

I might have all of this on my new website.
 

barfl2

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Regarding the never ending question here is a photo of my needle.

5268_needle_position_007.jpg


This slides along the bottom and right into the ink tank. Not had any problems with a ridge. This is a CLI-8 Cart also use mainly BCI-6. Because I had problems originally like everybody else I prepared a paper jig to stick onto my carts. This solved the problem and I only use 1mm drill for 20G needles.

Rest of discussions very interesting and my thanks to all contributors.

barfl2
 

panos

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mikling's theory can prove helpful to those refilling a dry cartridge with the Durchstich method.

However I don't agree to his point about the German method causing refilling problems on dry sponges for the simple reason that I had these problems and indeed in a much larger scale when I was top refilling purged cartridges.

purged_cartridge_squeezing.jpg


Of course I don't think the Durchstich method would give me better results even though Rodbam's initial photo on this thread shows a much better case of filling dry cartridges with the German method.

The thing is that I no longer care about these issues, not because the Durchstich is better or worse than top refilling on dry cartridges but because I no longer purge. My cartridges, after all these years still work perfectly which is a great relief because regular purging was a solution to a real problem, that top-refilled cartridges would stop working for some reason :/

I can't figure out why this isn't a problem with the German method, and I would really love to find an explanation some day on the forum :rolleyes:

But I do hope that you would not post an article on your website that could deter your clients from using this great method...
 

mikling

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See panos, the messenger gets shot again. I proved my point. I explicitly state I am not against it but there are pitfalls not in theory but demonstrated it. One just needs to know what is going on. Furthermore I sell stuff to use this method I just point out what the pitfall is and you're hoping I won't I deter it. I just don't understand the reasoning. Then why would I sell 2" needles to use?

I was hoping that the attitude that I do it that way so it MUST be right could be supplemented with facts, theory and demonstrations and not just fanaticism which can exist so much on the internet. A balanced approach that demonstrates both the good and bad is the correct way and then the person chooses whatever method they prefer. In my demo, each tank was refilled was via the german method if you did not realize that.

There were multiple questions about lower holes, higher holes etc. Essentially this was all pointless because it does not matter.

Sometimes things which appear obvious are not really so. Everything in life has this aspect. I do not think you understood the inkbridge issue and I think rod's cartridges would have worked as long as the outlet was saturated. There is NO need to get color up on the upper sponge as it soon becomes drained in any case.

There is a reason why there is some color on the upper sponge on Canon's OEM cartridges and it has to do with a couple things if you think through it logically. The use a ball to seal the tank. They use the label to seal the air vent. The label must go on AFTER the ball is placed on and actually truly seals the ball opening. That should tell you why the sponge will absorb enough ink to allow the top layer to wick some up.

The reason we are fooled by the upper sponge is that the upper sponge undergoes some compression when it is placed inside the cartridge. This naturally causes the exterior to get squished and brings the fibers closer. By having the fibers close to the smooth walls and closer when squished, ink is able to wick up in these areas better. So it looks like it has lots of ink on the outside. You can see this effect on the corners of the cartridges in the beginning of the thread. The ink appears to run up on the corners and sides because that is where the squeezing of the sponge occurs.

Also about the air travelling through the sponge. I don't think it is really an issue. When the sponge is cut and the fibers and predominantly longitudinal the cut edges will face the separation wall. So essentially it would like be a set of bristles against the separation wall. This will easily let air pass through when required as the top is drained.

These simple cartridges have a lot of engineering contained within them and have been refined over three generations. It is important to understand the principle of operation.

I welcome anyone to perform the experiments and show otherwise clearly because this is the only way forward just like it is done in scientific circles.
 

martin0reg

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This is a real in-depth review from mikling, thank you for analysis.

Regarding the potential issue called "broken ink bridge":
This might occur in certain cases - but IMHO this problem has to occur mostly when refilling a flushed and dry cartridge with no ink bridge yet.

edit: I wonder what is more easy/difficult in practical use: to establish the bridge or the gap?

Now when I refill such a dry cart (german method), the lower sponge always BEGINS to suck. In fact sometimes it doesn't suck enough to reach the outlet port - but this is due to a bad sucking sponge (or bad air exchange, no bubbles) isn't it?
At the beginning of this thread rodbam describes a similar problem, bad sucking but not no sucking...
As you said, canon introduced this groove at the bottom (CLI) to avoid a broken ink bridge. So it might had occured even in canon's own OEM filled cartridges (BCI-6)
 

slocumeddie

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Mike....

Would Canon's change(re improvement) from BCI to CLI cartridges be a good reason to use CLI's in older printers(example-IP3000), to provide an extra measure of reliability ?
 

panos

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I am sorry but I do not understand the relation of your response to my posting.

I did not make any points about the location of the holes, the upper sponge and soaking irregularity thereof or the air travelling. Also I didn't make any personal attacks, so the messenger is not shot. A simple disagreement is not a personal attack.

I understand you are claiming the Durchstich method may not allow for a proper refill of a dried cartridge because the bottom sponge (and especially the ink ridge) may not be soaked with ink in certain cases.

My 1st point is that this problem also exists in top refilling. In my old posting linked above I was describing this problem when I was trying to refill dried purged cartridges: the bottom sponge would not be refilled as it was evident in one of your photos. Only that I was not using the German method which you accuse of being responsible for the problem, but the top refilling method instead.

My 2nd point is that this is not a real issue in the German method because in refilling the sponge is not dried anyway. The problem with dried sponges was due to the fact that we had to purge our cartridges and then dry out the water to avoid diluting the ink. But purging is not necessary with the German method.
 

websnail

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Just quickly on the issue of "dried sponges"...

Having taken on board what Mikling has provided in the various posts above (with thanks) I think I can hazzard an educated guess.

When the sponges are dried out it seems the primary issue is re-establishing the "bridge" (as we now seem to be referring to it) between the spongeless tank and the sponge.

@Panos: I suspect the reason you are finding it doesn't affect you with your current "refill without flushing" method is that you never dry up the sponge and break the bridge.

In essence I think that indicates agreement, just from different viewpoints.


In many ways it seems that one of the reasons vacuum refilling is so successful at avoiding this (ignoring the vent fill/clog issue) is that it by its very nature it has to go via the sponge to the tank and re-establish the bridge before it can get there. Top-filling or German, relies on ink being introduced directly to the tank, bypassing the sponge and so may not re-establish the bridge.

The solution for each method seems to be:

Top-fill
1. Fill the tank as normal
2. Remove the exit port cover/tape
3. Briefly expose the fill hole to air
This removes the vacuum/negative pressure on the ink allowing it to apply full pressure downwards into the sponge and start dripping out of the exit port
4. Re-cover the fill hole
... then re-apply the exit port cover/tape so you can top off the tank and plug the fill hole


German Method
1. As you withdraw the needle, continue to trickle feed ink into the cartridge sponge.


... and just to be clear, the 4 v' 1 step thing is not indicative of which to choose... I like both methods..



Corrections welcome...
 

rodbam

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I found Panos reply to your post quite reasonable Mike so I don't know why you responded like that, maybe there's some past history I'm not aware of. The ink bridge is a new & revealing piece of information that I haven't seen mentioned before & it can explain why there are some problems sometimes. I can see how the top fill method doesn't interfere with this bridge as the German method might do in some cases but I was wondering if just the act of withdrawing the needle out of the ink chamber would drag some ink with it so restoring the ink bridge especially if the cartridge is turned right way up before withdrawing the needle as I do so the small pocket of air goes to the top of cartridge before taking the needle out. Of course we could just inject ink as we withdraw the needle to make 100% sure the bridge is connected.
I think we can all agree that whatever method one is happy with is the right method but one thing I can do that I can't do with the top fill method is to fill my ink well to the top & I consider a full cartridge is a happy cartridge:)
 

The Hat

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mikling sit down and the fans of the German method, don' t take offense.
panos I did not make any points about the location of the holes, the upper sponge and soaking irregularity thereof or the air travelling. Also I didn't make any personal attacks, so the messenger is not shot. A simple disagreement is not a personal attack.
panos I can see where youre coming from alright but instead of questioning mikling theorys you disagreed with them and so... shot the messenger.

So there, it is not as some may have interpreted that I am against German refills, and cause some hate to run within their veins but rather I can see some issues that could take a lot of explaining to show. These issues are never present with the top fill. Some of the issues against top fill that are promulgated by the advocates of german refill methods have shown to be incorrect and false.

You can refill ANY way you want, it's a free world in some parts but just be aware of what you are doing and take the steps to make sure it is correct.
I would suggest you read through the thread again and youll see the facts that mikling presented
are not directly critical of the German method but any filling method that may disturb the ink bridge will also have this problem.

I dont use the German method because I probably hit the very same problems when trying to refill some purge cartridges.
 
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