Purging the PGI-9 cartridges

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Excellent information here that I'm carefully reading because there was a special on the Pro9500 bundled with $300 of Canon A3 paper so my missus made me buy one for $699, yes for once I wish I was a Yank

... and then you remember who is running for president.. *steps away from the very large minefield*

Now what is my safest refill method to begin with, dribble or the Freedom method?

"Safest" would be the dribble method in the sense of slow and sure but if you're starting from scratch on most cartridges you're going to be talking quite a long haul... and to get the best of both worlds a combined force-fill + dribble top-up seems to be a good option.

The thing that confuses me after watching the Hats & (Joe) Jtoolman excellent videos is the sucking out of air, in Joe's video he didn't suck air out before filling on a half full cart but the Hat sucked air out from an empty cart. What would happen if you just injected ink in without sucking out first?

If you dribble ink in then the air is slowly forced out and you would only see this if you somehow managed to flood the cartridge sponge enough for a bubble to appear on the sponge surface. Given the surface area size that's unlikely so it's not visually obvious what's going on.

With the force fill (what I believe you are calling the "freedom method") if the air wasn't removed first you would be forcing ink in but not allowing air to escape so you wouldn't be able to just push ink in and expect the cartridge to be full of ink when you hit resistance. Instead you would have to withdraw pressure (with the cartridge up-ended) to allow air to be pulled out and then repeat ingress of ink until you were sure that the cartridge contained only ink and not air.

As a result, removing the air first when force filling, is preferable as you don't have to do lots of push, pull, push, pull to get to full.

The other thing that puzzles me is the cleaning/purging of these carts, I can understand how you put water in but how do you get the water out & get the cart almost dry? Edit. I've just read Martins bit about sucking the water out with a reverse of the Freedom method.

From memory almost all of the posts to just recently, mentioned filling only cartridges currently in use and flushing has just reared its head. As a result I don't think anyone really considered the ins and outs of flushing properly until now, in fact almost all flushing discussion has focused on how to get the sponge clear of any dried ink or clogging.

Pulling the ink out using a mod'd clip is IMHO the best approach (as noted) but the other way might be the one used with other Canon carts (ref ) but that would require the cartridge to right side up and be VERY slow/wasteful. The only other approach would require a more professional equipment setup (ie: vaccum pump and container) to purge the cartridges but to the same effect as the mod'd clip.

Note: Anticipating the come back on use of a mod'd clip... The sponge does need to be clear of junk/dried ink so the mod'd clip is only part of the equation. In terms of purging the cartridge it's the most sensible and cost (time & money) effective approach.

Does this sucking pull the bag in too tight on itself if you over suck, or is the restriction you feel in the syringe all that's needed for not overdoing it?

You feel the restriction.. I did try to over pressure the vacuum with a 60ml capacity syringe at one point and the bag held fine but obviously I wouldn't recommend that approach as it's going to cause stress over time. Common sense would seem to apply in how you deal with it... ie: don't go crazy!

I will be sober in the morning when I read your replies so can you reply whilst still sober, thank you.

Well the hiccuping and slurred typing was a tad off putting

 

[The Hat]

rodbam
You have raised some good questions as to the hows and whens of refilling but once youre in the thick of it you'll soon find the most convenient way to fill and the one youre most comfortable with.

You need not worry about the durability of the inner bag in these cartridges;
its made of good stuff and wont burst or get damaged easily. (How do I know?)

I used the suction method on one of my cartridges to see how weak/strong this inner bag was by filling it with water (Very full) and then with the cartridge held above the syringe sucked out all of the water again by pulling back on the plunger of the 60 ml syringe I was using.

Now I did this not once but fifty times and stopped because I figured that was enough
to prove that the bag wont bust using this repeatable filling method over time.

I went further with another destructive test I filled the syringe with 30 ml of water and tried to squeeze as much of it into a cartridge by pushing down hard on the plunger to the point that the cartridge
casing burst and the inner bag protruded out through the sides of the cartridge.

Surprisingly the bag didnt tear or split and I was able to push the bag back inside the cartridge and then test for leaks but there were none.

There's one odd thing about the PGI-9 cartridge and that is the casing is not air tight or waterproof so if there is the slights failure of the inner bag then ink will leak out into your hands.

Cleaning of the cartridge is just the reverse of filling except using soapy water and if left close to a mild heat source or (left in a sunny window) for an hour the small outlet sponge will dry very quickly.

 

[mikling]

The issue appears still not to be obvious.

The reason why the casing leaks air is because it is fundamental to the way the cartridge works with the bladder. If it did not leak air the bladder would NOT collapse and ink would not exit.

Now that I have thought about it more. The issue that had been missed for such a long time is the likely culprit and it would not rear its head until long term use.

My conclusion is that the dribble method in combination with a scale might well be the safest and most foolproof method long term. Here are the reasons why.

1. If you start out with a new cartridge, use it normally and refill it with the dribble method, you will just about never get air inside the cartridge. The reason is simple if you understand the force of surface tension. The close proximity of the fibres in the pad will very much block any air from entering the pad and thus cartridge provided the pad is soaked with ink. The key is to have the pad maintained in a wet or moist state at all times. With normal use this will always be the case. Having the digital scale guarantees the fill level with no doubt whatsoever.

If the pad is left to dry out as when you recover old discarded cartridges, then the spring may have pushed out the diaphragm because the dried ink is no longer bridging the spaces between the fibers in the pad and air can get through. This is once instance where air can enter. If you start out with good cartridges and never let them dry out, then you can pretty much forget about this issue.

The other instance where air can enter is the fill using the orange clip. Any air that gets trapped between the tip of of the syringe and the pad during the fill process can potentially get into the cartridge. In these instances, using the same jig, you'd have to reverse fill or remove the air that is at the top of the cartridge.

Nobody has mentioned the flawed air removal as yet. What is it? That there are corners to this flat bottom of the cartridge. If you have a bubble it will behave as it does in a liquid level. The little bubble will have to be "precisely" at the exit point of the bladder ( approx 3-4mm) AND you'd have to be drawing out with the syringe at the same time. The exit point is not at the corner or that would be too easy.
The only way to get the air out at this point is to totally collapse the bladder to squeeze it out. ...and then refill.....

Now I would then weigh the likelihood of air re-entering again at this point. Which method will have less potential of doing so...I would suggest the dribble method.

Now I had previously mentioned the issue of pigment dropout and settlement. This could be a potential issue in long term refilling. Now let's review the pad that goes onto the cartridge... the clip. Inspect it carefully with a set of magnifiers. Jtoolman can help us because he has a machine shop and probably has a set of depth gauges. You will observe that there is a sealing ring and that the large surface actually is raised as compared to the ring around it. In any case. the flat surface is not recessed but rather the opposite. When attached to the cartridge it might actually touch the pad surface but even if it did not, there is one rule that reigns supreme. Liquid like current flow always follows the path of least resistance and quite often this is the shortest path. When there are multiple paths, the amount that flows will be disproportional to the resistance in that path.

So I will point out again that using the cap concentrates the ink to enter at a localized spot and this may be even more so, if the silicone flat contacts the porous pad. The ink then find the easiest path to the inside of the bladder. It thus bypasses most of the distribution channels and is thus unable to redisperse any pigment build up there. With the dribble method, efforts to re-disperse pigments and buildup are more effective because during the refill you can direct the ink at various locations to force redistribution that the alternative method is not able to do.

Since I issue instructions and customers depend on these to refill their cartridges, I will take the side of caution by suggesting that the dribble method be used. This way, with each refill, re-dispersion is always carried out and the cartridge has the best chance to be always in tip top shape thus minimizing the risk to the costly printhead. I will have provided the best instructions possible. If an alternative speedier process is found and is within the boundaries of "safe enough" by them then by all means they can proceed. I will not stand in the way. It is important however, that they be made aware of the potential issues and then the explanation of that would be too complicated for the hapless soul who just wanted to save some money....in other words "It's complicated".

Be careful of soap and detergents. These are dispersants that indeed break down the ink, remnants of this even when the water has dried out, can cause more settling or dropout than normal when ink is reintroduced. Drying out, removes only the water in the pad. The chemicals remain within the pad and inside the bladder. This might not be good. My picture of the expanded bellows clearly shows ink remaining inside even when extracted and emptied. So any liquid thatis used to clean inside must be removed as much as possible. . This is why I use ink base. It would be wise is to perform a small flush using ink itself after using soap and water....to mitigate any potential issue. That is the reason why my refurbed carts always have a small bit of ink in inside but like I said I don't use soap and water. I use ink base in combination with a concentrated vacuum needle that directly removes pigments from the pad at selected points. It's a little more professional approach but I have collected the resources required over the years.

But in all of this "flushing" that I perform and discussed it is ONLY for the recovered cartridges that have been left in a dried out state and the ones that have become plugged up for some reason.

 

[ThrillaMozilla]

I second the concern about impurities left in the bag due to purging. The ink is a colloid suspension. Small amounts of impurities can cause the colloid particles to aggregate and settle, by a process known as flocculation. While I was testing the light stability of ink, I diluted some pigment ink. The flocculation was dramatic, and I can tell you, you do not want that to happen. You can read a little about flocculation here: http://en.wikipedia.org/wiki/Flocculation and here: en.wikipedia.org/wiki/Clarifying_agent . I know many of you have a lot of experience purging cartridges, but in many cases dye ink was used, which will not flocculate. If I were doing the purging, I would be very careful of what materials I used, and would run some tests in advance.

I also have a suggestion for refilling. The main disadvantage of the dribble method seems to be speed. The advantage is that it's very slow and gentle, and it cannot introduce air. I suspect that it would be quite easy to increase the speed of filling just by flooding the surface instead of filling dropwise.The trick is to do so without making a mess. It shouldn't be that difficult to construct a barrier to contain a spill. Just a little raised rim around the edge would be sufficient just to try it. You could also use a dropper or something else that delivers faster than a syringe (which tends to either drip slowly or squirt).

For a more permanent solution, The Hat's clip could be modified to include two holes -- one for the syringe and one to let air out. If the air vent also incorporated a tube pointing straight up, that would give additional insurance against overflow. The vent would work something like a drain vent in house plumbing. Since you couldn't refill on the balance (aka "scale"), you might want to combine this with JToolman's dribble method for a clean, precision finish. I believe this method would be slow, gentle, and fast, without any possibility of introducing air.

 

[The Hat]

The reason why the casing leaks air is because it is fundamental to the way the cartridge works with the bladder.
If it did not leak air the bladder would NOT collapse and ink would not exit.

A cartridge can have air or vent holes in it if necessary that goes without saying
but it doesnt mean it cant be leak proof also. (Thats just my point of view on it)

The only way to get the air out at this point is to totally collapse the bladder to squeeze it out. ...and then refill.....

With the method I use thats exactly what I do before I allow the ink back into the cartridge.

Since I issue instructions and customers depend on these to refill their cartridges,
I will take the side of caution by suggesting that the dribble method be used.

I understand you have to be very cautious with any information youre promoting,
and therefore tend to take the belt and braces approach to the best filling practices,
I would probability do the very same if I were in your position.

But in general its about the best way for the refiller to try out the different methods themselves and it also lets them be their own judge on it.

Refillers know that there is a certain element of risk involved in refilling any cartridge and it seems that most are prepared to take that risk, they wouldnt be bothered reading up on all of this information otherwise.

I omitted to mention in my earlier thread above that when cleaning the cartridges with soapy water, I also rinse them thoroughly with clean water afterwards to insure there is no chemical
residue left inside and especially on the outlet sponge material.

 

[rodbam]

Fantastic replies mates, thank you all very much. Until I get comfortable with refilling these cartridges I will use the dribble method for my own piece of mind & then no doubt graduate to the more speedy force fill. Now all I have to do is to get my mind around paying for the new resetter which is the thing that got me on to buying the 9500 in the first place.
The little scales you use, do these have to be top quality? I
I've had a look on the net & they range in price from $8 up to $70 (There are some of course way above these prices) What is a good bang for buck scale that will do the job? Don't forget I'm not as rich as you lot
After reading Thrilla's post I was wondering if a clip could be made up with a hole cut in the size of the sponge where we could deposit a few mls of ink at a time, if we could build up around the hole in the clip we could deposit even more ink in. Am I get ahead of myself seeing as how the printer is still in the box
Thanks again for all the help. I feel really lucky because when I first came here the refilling of CLI8 cartridges was a popular topic which made it easier for me to learn how to refill the 9000, now the PGI9 refilling is getting a good run in time for me to learn refilling these & at last we have a resetter.

 

[ThrillaMozilla]

Gosh, Rodbam, I haven't looked at scales for a few months, and I don't know about Oz, but Amazon.com had Chinese like Toolman's for under US$20. Maybe $10-15 with delivery. I've got two different kinds. I have VERY good equipment to check them against, and they're both top quality. Calibration will be pretty close, but it's also a good idea to spend another $3 to get a 100 g weight for calibration.

 

[The Hat]

I decide to try another approach to the dribble method which was suggested by ThrillaMozilla.
Making and using a new orange clip with a large hole cut out of the top to provide a bigger reservoir for the ink with a lesser chance for spillage and speeding up the process into the bargain.

The single biggest drawback with the dribble method is its slowness, because filling a cartridge from scratch can take ages, but on the other hand for topping up it is by far the best and fastest method.

I decided to use water instead of ink for my first attempt at refilling, I put the clip with its brand new large hole onto the cartridge and dribbled a couple of drops of alcohol onto the sponge area just to make sure that the sponge was moist enough to accept the water.

It started well enough but soon ground to a near halt it seemed to be faster at first
but Id have grown a beard before the cartridge was full.

I then decided to try it with ink a second time and soon realised that the standard dribble method without this new clip was just as effective and probably overall faster.

There is air trapped just under the sponge area above the channels that lead down into the bag and this air (Its probably a big bubble), is what the ink then has to navigate around to be able to enter the cartridge.

If this air was not present or was pushed down into the cartridge then ink would be able to travel much easier and unrestricted into the cartridge.

The dribble method by itself cant dislodge or push this air out of its way so is forced to work slowly around it, any method that cant remove this air will always be slower.

The three small drain holes in the top of the cartridge inlet when combined together are capable of accepting a larger volume of ink than my syringe or the new SquEasy bottle refill method can provide, but by using either of these two methods with moderate pressure they can overwhelm the air problem making them much faster.

The small sponge on the inlet of these cartridges is only 1 mm thick and by itself wouldnt cause any air or ink flow problems but laminated to the underside of it is an extremely thin piece of steel mess (Filter).

This filter which can trap just about anything (Including air) so keeping it free from all sorts of debris is vital if you want the cartridge to perform at its very best and I think this is where the whole debate on the purging issue started.

 

[rodbam]

If the force fill method has any doubts then I wonder if extracting the air out of the cart bag with the syringe like you did in your video & then using this newer dribble method, would this speed up the flow of ink into the cartridge?
I was thinking of using some clear plastic tubing by making it into an oval shape & gluing this around the larger clip hole, the tubing could be an inch or two high & would add some head pressure to help push the ink in.
Anyhow Hat thanks for your timely (for me) work on the PGI9 cartridge.
One thing about the purging, if nothing much can pass that filter screen then if we purge the cartridge we can't really remove any impurities out of the cartridge, can we?
I think I'm starting to sound intelligent since I got a pigment printer

 

[mikling]

Testing with water will be invalid because the liquid properties of water is different from the ink even though the ink is water-based. Chemicals are added to modify the physical properties of water based inks.

So the saturation point of the pad will be different if water is used as compared to ink. Simplistically, when you over saturate the pad as when refilling with the dribble/stream; the pad then wants to give off the excess ink beyond the saturation point. This excess ink is released by the pad and the vacuum within the bladder created by the spring draws the ink back into the bladder. Gravitational forces is not the major force causing the ink to re-enter but it helps. You might be able to refill the cartridge with it lying on its' side if you are patient enough. At all times there is an equilibrium of forces created by the ink wanting to "stick" to the pad and what the spring wants to draw back in.

As Thrilla and I have stated previously, if all that is done is removal of ink and replacement of ink via the pad and the pad has remained wet, the possibility of getting air inside even under the pad is close to nil. You must grasp this concept. The saturated pad will block any air trying to enter. Vacuum forces created by the spring are not strong enough to force the ink trapped between the fibers to separate and allow air through. You need to visualize this at a lower level.

It is no longer the fill that I would be focused on now but rather the re dispersion of the pigment that had settled in the pad and amongst the distribution channels. This I think should be one of the goals during the refill.

Again this is in simplistic terms as best most people will be able to understand.