Mike Chaney's Tech Corner

This thread is relevant to the Canon  CLI-42 OEM cartridges, but may have some relevance to other Canon catridges and in particular the CLI-8s.

For those of you who have been reading my thread on Purge cycles for the Pro-100S, you will know  my testing suggested there was about 3.5g (approx  3.5ml) of wasted ink left in the sponge when the printer reports the cart as empty.  The cart is usually thrown out at this point, unless you intend refilling with 3rd party ink.  The 3.5 figure is based on the assumption that the cart starts with 13ml of ink when full.

I came up with the crazy idea, for OEM users, of harvesting this wasted ink from 3 carts and refilling a 4th empty cart.  Since then I have determined that there must be even more ink in the sponge of the cart reported as empty.   In fact the figure is more like 4.26g.  I say this because I remembered Jose (Jtoolman) measured an empty cart he had been preparing to refill and he got it down to 13.58g.

So the simple maths:
Weight of new full cart = 27.33g
Weight of Virgin cart = 13.58g
Hence Total ink in a full cart is 27.33g – 13.58g = 13.75g   (Not 13g as had been assumed)

My Gray cart was reported empty at 17.84g.  Hence 17.84g – 13.58g = 4.26g left in sponge .

So percentage of ink left in sponge and typically thrown away is 30.98%.

I decided to do a simple test of how much ink can be extracted from an empty cart.  I did not want to start with an OEM cart so I used a 3rd party CLI-8 cart that was almost at the low ink level.  My guess is there was about 0.5g of ink in the compartment side of the cart.
I should have taken it down to the low level before starting, to be more accurate, but I figured the sponges are different to the OEM so accuracy was never going to be possible.  I just wanted to prove the concept.

The method of removing the ink was to use a plastic base clip which is intended to cover the exit hole and modify by inserting a shortened needle into the silicone washer seal.  The best way for you to see this is to look at the one made by Jtoolman on this video link: https://youtu.be/ACc0Bw5nicY

The same video mentions the virgin cart weight.  I did not even have to glue my clip like Jose did, because the needle was a tight fit through the silicon washer.  The syringe I used is quite big with a 22ml capacity.

The extraction went very well, taking only about 30s.  I slowly drew the syringe all the way out, which  brought a lot of air as well of course.  I then just waited a minute or so for the bubbles to disperse.  The 0.5g of ink that was in the tank remained until after I had pulled the syringe to it’s full extent, it then slowly moved into the sponge.  So a second attempt would probably have harvested some of that as well.

The amount harvested in just one single draw on the syringe was 3.97g.  Bear in mind that this cart was not reported as empty.  From testing my Pro-100 I know the low ink level is reported when there is about 5.22g left, which equates to 38% of the ink left.  So I think the ink yield is a satisfying result for just one quick draw on the syringe.

I also queried Jose about refilling a cart to 90%.  He agreed that that is at about the upper limit and that 80% was generally considered a good practice.

So here is a potential workflow:
1.   Stop using a cart when it gets down to 40% left (Not quite ink low level)
2.   When you have 2 stored empty carts, extract the ink from one (Donor)  and inject into the other (Recipient).  The Recipient cart needs to be reset and modified to allow refilling.
3.    When the next cart reaches 40%, remove it and replace with the Recipient cart.

One problem with this workflow is that it assumes 40% from both carts.  The donor cart will not yield 40%.  So the recipient cart  may only end up with say 75% instead of 80%.  However, I don’t think it’s an issue.  I believe what will happen is that when you first install the Recipient cart the printer driver will report 100%, due to the reset.  As ink is used it will drop gradually, but I assume at some point the prism in the cart will pick up that it has less ink than estimated by the usage and the ink level warnings will suddenly drop drastically.  It would be interesting to get some feedback on this assumption from seasoned re-fillers.

If it is an issue the options are to either not let the carts get as low as 40% or to use 2 donor carts instead of one.

The workflow is constructed, for the Canon Pro-100S in a way to avoid unnecessary purges of ink.  If you have the recipient cart ready when you take the current cart out to replace, and do the swap in less than 60s, there should be no purge.  The same applies to any cart swap, as long as the accumulated time a cart is out of the printer, since the last purge, does not exceed 60s, there should be no purge.

I currently have only one used OEM CLI-42 cart that has been removed from the printer.  In this case it was identified as empty by the printer driver.  Hence, it only contains about 31% of the original ink.  I will have to modify the workflow slightly for the first attempt.  eg.  I could take the next cart out at 50% full.


Bruce

Bruce,

Good stuff as always!  If that syringe gadget can be made to be that efficient and you can refill the recipient cart without much mess, this might be worth the effort if you are on OEM ink.  But let me ask you this.  Is the Pro-100 like older Canon printers where it will let you continue to print after the cart is read as empty by the driver?  I remember I could do that on my Pro-9000: I don't remember if you had to pop the cart out/in or just keep printing but you could actually continue printing until it ran dry and ruined the head.

The reason I ask is: what if you just kept printing when it said a cart is empty knowing there is 3+ml of ink still left in the sponge?  Then just weigh the cart every few prints and replace it when it gets down to 14g.  Of course, the dangers are:

- If you forget or print too long between weigh-ins, you could ruin the printer
- There may be some question of whether the sponge can deliver enough ink (fast enough) when not saturated

On that second one, the fact that you could suck the sponge nearly dry in just a few seconds with a syringe might indicate that the sponge is efficient enough to keep delivering ink at required rates until it is almost dry.

Thoughts?

I'm just trying to figure out an easier way without needing gadgets.  Yet another idea on the "extraction gadget"... what if we were to make a flexible ~6 inch tube that fits (air tight) between the donor and recipient's exit holes?  Then bend the tube in a U so that both carts are upright and use the syringe to suck from the top airhole in the recipient cart (plastic ball would have to be removed) and the ink would go from donor directly to recipient?  I could imagine some clever gadget that could be manufactured where you pop in two carts and controlled suction/pressure would transfer the sponge ink from donor to recipient.  Hmm... just gave away an invention idea.  ;)

Last thought: I belive those carts are supposed to be sealed so where is the air coming from when you suck the ink out (if you don't remove the plastic fill-hole ball)?  Or... is no air entering and you are just creating a partial vacuum in the cart?  Similarly, when you go to push that ink into the recipient cart (again if you don't remove that plastic ball), you'll be creating pressure in the recipient cart and when you remove the syringe, it's gonna spray that ink back out the exit hole.  I suppose there must be some tiny air holes in addition to the fill hole though, else the cart would never empty, so there's that.  Question is, how quickly can pressure equalize when using a syringe.  Or, maybe there are NOT any pressure relief holes and pressure is just relieved at the exit hole since that is not an airtight seal?

So many questions.  :D

Mike

I think it’s too risky to keep printing, even if the printer lets you.  Printheads are very expensive and the extra effort of transferring to another cartridge is not that big a deal once you got the few extra tools needed.  I certainly would not want to be weighing in-between every couple of prints because you only have 60s total accumulated time to have the cart out of the printer before a purge will result and ruin everything.  Measing the weight of 8 carts several times makes for a lot more work than transferring the ink.  You would also need to keep careful notes about each cart.


The cart I was drawing ink from was a 3rd party cart with a single sponge.  The OEM carts have 2 sponges, presumable with different densities.  So until we try the same method on an OEM cart it is difficult to know an answer to your question.  I note in Jose’s video he said there was about 5ml of water in the sponge and he also had the vent on top of the liquid chamber open.  I did not have the vent open.  Jose seemed to be getting just droplets.

Related to the fact that it was not an OEM cart that I tested, and I was having all sorts of problems with my Pro9000, which is where the carts came from, it is very likely the sponge has more ink than it should.  With the OEMs the ink tends to be mainly in the bottom sponge.  With these 3rd party carts the ink is well up the sponge.  It is very possible that I mistakenly thought I had a printhead issue when in fact it was a cartridge issue and in my attempt to fix a good printhead I burnt out the printhead as well.  I bought a replacement printhead but decided to buy the Pro100 before it arrived.

I am beginning to think I should just test the single "Empty" OEM cart I have and somehow store the ink until it is needed, just so I know this technique is worth pursuing. I will think on it.


That could work.  You may be interested in the gadget Jose discussed at the last Techie talk:
https://youtu.be/Ahstv2v64I0?t=1h12m35s



There is an air hole on the sponge side.  It is in a L shape and I believe it is sealed when the cart is packaged.  Removing the packaging unseals that vent.  I assumed that is where the air came from.  The other possibility is that I did not use glue on my modified plastic clip, so maybe there is a pressure leak there.


There are a lot of combinations of potential workflows.  The 2 simplest would appear to be to either remove the cart when the “Low Ink Warning” starts. ( ie.  38% left), or when the “Empty Warning” appears.  (ie. 31% left).  With the “Empty” option you could probably use 3 empty carts to get somewhere in the mid to high 80% area.  With the “Low” option, 2 carts are probably going to give somewhere in the low 70% area and 3 carts will result in more than you need, which means you have to hold on to that small amount of extra ink for a potentially long time.

Bruce

I bit the bullet and started extracting ink from my “Empty” Gray OEM cart today.

The short description is that I extracted 2.72g of ink.

I used the same equipment as the last time, but repeated it several times to see how much I could get  just using a simple syringe.  I recorded most of what I did on video.  It’s quite boring, so I have not uploaded any of the recordings.

I deliberately took my time.  Here is a summary of what I did:

1.   When I started, the cart weighed 17.87g.  I left some cello-tape on the cart, covering the vent at the top of the sponge side.   That is why it weighs 0.03g more than when I took it out of the printer.
2.   I took my time on the first draw back of the syringe (about 2.5 min)
3.    Weighed the cart – (16.29g) and returned the syringe towards closed position
4.   Second drawback (about 2min)
5.   Weighed again (15.74g) and returned the syringe towards closed position
6.   Third drawback (about 1m 25s)
7.   Weighed again (15.5g) and returned syringe toward closed position
8.   Fourth drawback (about 45s) slowly returned syringe to closed while cart still connected.
9.   Fifth drawback (15s)
10.   Weighed (15.41g) and returned the syringe towards closed position
11.   Sixth through to Tenth drawback (30s, 10s, 10s, 5s, 5s) with cart still attached to syringe.
12   Final weight 15.15g

Ink recover = 17.87g – 15.15g = 2.72g (almost 20% of a full cart)

So theoretically there is still 15.15g – 0.03g – 13.58g = 1.54g left in the cart.

I am quite sure I can speed up the process a lot. I am not so sure I can get much more ink out of the cart.

The 20% may at first seem disappointing, but a more logical way to look at this is that the 2.72g is better than 28% of the ink that is currently usable.
ie.  Only 9.49g of a cart is currently usable.

Bruce

Nice work.  I wonder if you could get more ink out by covering the sponge hole and slinging it with the hole facing outward.  I do that with ketchup bottles to get all the ketchup into the neck of the bottle.  :)

Mike

When I cleaned the plastic clip after yesterdays effort I noticed it had started to come apart, since I had not used any glue like Jose had.
So I figured it was worth trying again, starting at the same place I left off yesterday.
Because of the vacuum formed in the cart, if you let go of the syringe handle it tried to go back-in part of the way.  So I tried a short pumping type action, by letting the syringe return a bit before I resumed.  It seemed to help.
So after the first attempt the cart weighed 15.04g.
I tried a jerking type action on the cart to force ink towards the exit port.  Not quite the slinging action suggested by Mike but should have a similar effect.
I connected the syringe again and used the same pumping action as before and weighed the cart to get a final result of 14.91g.

The total amount of ink recovered now is 2.96g, which represents a 31.1% increase in ink available.  Leaving 1.33g in the cart.
It's a cumbersome way to get the last few dregs, but it does indicate that there is potential if a better technique can be devised.
I was considering taking a purge unit out of an old printer and using it instead of a syringe.  Not sure how much pressure they can exert compared to a syringe.  Not everyone would have access to an old printer though.
I tend to keep them.  They may come in handy one day. ;D
If the purge unit does work better than a syringe it may then be worth working on a solution based on commercially available parts.
Bruce 

Curious... maybe I just don't understand...

Why would you tape the pressure relief groove on the cart, causing a vacuum when you use the syringe?  Why wouldn't you leave that open so air can enter the cart to replace the removed ink and the syringe can draw freely?

Mike

Good question.  I meant to explain that earlier.  When I first took the cart out of the printer I taped the vent closed based on advise that if I ever intended using the cart in future for refilling, this stops the sponge drying out and rendering the cart unusable in future.  Although I think you can use rejuvenation fluid to bring it back to life, using the tape is the easiest option.

When I decided to try extracting ink, I decided to see what happens if I did it with the tape still in place.  If it did not work I could remove the tape and try again.
Seeing as it did work I never bothered trying it without the tape. When I tried drawing ink from the 3rd party cart there was no tape over the vent.  In that case there was a lot of air bubbles in the syringe.  In the taped off OEM case the bubbles tended not to form.

I will try to remove more ink out of the OEM cart with the tape off, but first want to glue the shortened syringe needle into the plastic clip.  Waiting for tomorrow, when ALDI have a special on Bondic Liquid Plastic Welder.

Bruce

OK, sounds good.  I wouldn't think bubbles would hurt anything.  They'd just dissipate in the syringe and you could tap it afterward and push the syringe up to get the air out.  I'm thinking I could 3D print a cart-to-syringe adapter for this.  :)

Mike

That sounds interesting.  When I was researching the Purge units used in printers I found cases where home 3D printers had been used to make these types of pumps.

Further on my attempts to extract ink from an empty cart:
I tried gluing the shortened needle  to the plastic clip using the Bondic.  It uses UV light to cure the glue in about 4 seconds.  It did not work on this type of plastic, so I tried a hot glue gun and that did work.

After the previous test the cart weighed 15.12g without the sticky tape.
I removed the sticky tape covering the vent on the sponge side of the cart and pulled the syringe quickly to full length.  Nothing much happened, so I slowly closed the syringe and opened it quickly.  A small drop came out.  I repeated a further 4 times and weighed the cart.  It now weighed 14.77g without any sticky tape.

I then made a small homemade centrifuge by glueing a 1/4in bolt to a metal lid of a biscuit tin (about 8.5 inch or 21.5cm  diameter).  I taped the cart to the inner rim of the lid with the exit port facing out, put the bolt in a cordless drill and spun the cart for about 20s.  (No tape on sponge side vent).

I connected the cart back up with the extraction needle and repeated the previous method, but did it about 12 times.  The cart now weighs 14.6g, so ink extracted today is 15.12g – 14.6g = 0.55g.  I have to say it looks very small in the syringe.  I don’t know that the centrifuge achieved much.

The total ink now extracted is 17.84g – 14.6g = 3.24g.  Which represents an increase of usable ink by 29.3%.  Ink left in the sponge is 14.6g – 13.58g – 1.02g.

My thoughts at this point are that a small pump would do a better (quicker) job, because it’s taken several goes to get this far.

I have extracted a purge unit from an old printer and may play around with it on some 3rd party carts.

Bruce

You may have gotten as much out as you can.  If you look at a sponge under a microscope, you'll see that it is just a lattice similar to a loofah but on a smaller scale.  When the ink is more soaked (before you suck it out), liquid ink is likely taking up the spaces or "holes" in the sponge lattice and that's what you are sucking out.  As you pull ink out, you'll end up at a point where you've sucked all the liquid ink out of the gaps and what you end up with is a coating of ink that covers the small lattice spines themselves.  You won't be able to suck that coating off the lattice because it is held on by surface tension and the air you are sucking through will just move past it.  I wouldn't be surprised if there is 1g of ink volume just coating the sponge lattice.

On top of that, as you suck ink out, you are probably creating pockets of dried ink in the sponge.  That's another question entirely: is the ink you are extracting going to be "valid" ink?  Is it possible that as you suck ink out, you create microscopic dried chunks in parts of the sponge as air goes by, leaving those invisible microscopic chunks in the extracted ink if it breaks off in later pulls on the same cart.  If so, could they cause clogs or other problems?  That's my only worry with this method, so...

Most likely, giving the cart a few pulls over a minute or two gets most of the ink out.  Beyond that, you're looking at diminishing returns and the possibility of creating clumping problems with the extracted ink.

Just some random thoughts.

Mike

Another thought.  I wonder how much ink you could get out if you cut open the top of the cart and pushed the sponge out by pushing a screwdriver into the exit hole to push it up and out of the cart.  Then (using rubber gloves), take the sponge and squeeze/fold it just enough to get the sponge INTO the large syringe.  Then push down on the syringe plunger to squeeze ink out of the sponge and out the tip of the syringe into a container?  This would only be worth the efffort based on how easy it is to cut off the top of the cart and deal with the "raw" sponge, plus getting the empty sponge back out of the syringe when done.  But might be an interesting experiment.

OK... just tore open a cart to see.  Turns out you can grab the little tab at the end of the cart and roll back the top:

(http://ddisoftware.com/tech/printers/canon-cli-42-oem-cartridges-wasted-ink/?action=dlattach;attach=9501;image)

It breaks when you get to the sponge part but you can stick a screwdriver under the sponge lid and pop that up too:

(http://ddisoftware.com/tech/printers/canon-cli-42-oem-cartridges-wasted-ink/?action=dlattach;attach=9503;image)

After rolling back that piece, the THREE sponges just drop out (pushed them through with a screwdriver):

(http://ddisoftware.com/tech/printers/canon-cli-42-oem-cartridges-wasted-ink/?action=dlattach;attach=9505;image)

I put all three in a big syringe and crushed them.  Didn't even get a drop of ink.  But this cart has been sitting around for a year with the sponge hole exposed.  It probably evaporated:

(http://ddisoftware.com/tech/printers/canon-cli-42-oem-cartridges-wasted-ink/?action=dlattach;attach=9507;image)

Anyway, interesting to see that there are three sponges in these carts and not two:

- A little "puck" at the exit hole
- A rectangular piece above that
- A piece with a different density at the top

Mike

Interesting that there are 3 sponges and not 2.  I guess it's easier to manufacture that way.

I was concerned that dry ink could get into the recovered ink.  From that point of view I would try recover as much as is reasonable in one attempt, rather that the strung out procedures I have used so far.  In fact I will probably throw the gray ink I have recovered from the current test cart.  After the first attempt at recovery I left the ink in the syringe overnight, with a normal needle inserted with the scabbard on.  The next day it was apparent that ink had leaked into both the scabbard and the hub between needle and syringe.  The syringe is a slip hub type, not the better luer lock hub type.  When I cleaned up the leaks and injected the remaining ink into a small bottle it felt like a clog had formed in the needle.  Which means it is very likely there is a small clump of ink in the collected ink.  So not worth the risk of reusing the ink.  I think the lesson is to recover and re-inject all in one session.
I think I may buy a better syringe though.

Bruce

Just an update on the use of a purge unit to extract ink from an empty OEM cart.

The purge unit I am using happens to be from a Canon MP540, which is a 5 ink multifunction printer.  It was not mine, someone was throwing it out and I grabbed it.  My preference would have been one of my old printers but I stripped them down last year so they took up less space and it appears I threw out all the purge units, because they tend to be messy.  The purge unit on the MP540 is buried deep inside the printer and I literally had to remove nearly every other module before I could get it out.

I started writing a description of a purge unit and decided it was way off topic.  Maybe I could start another thread.

The basic function of the purge unit that I was interested in using was it’s ability to pump ink.  It does this using a “Peristaltic Pump”, driven by a small electric motor.  I have attached 2 photos of the pump from the MP540; one with cover removed but drive gears still in place the second with the drive gears removed.  There is a tube where ink enters from the bottom left and exits to a waste ink pads on bottom right (see blue text).  The other tube ink enters top right and exits to waste pads on top left (see red text).

I could not find any technical details on the motor, other than a part number, so I assumed it was a 12V DC motor.  I also randomly selected polarity of power source, and got lucky.  If I had chosen the wrong polarity the purge unit performs a different function, so not a big deal.

I initially flushed some water through to clean out old ink.  Using the top (red marked) tube, I connected a third party empty cart to the IN side.  It was the same cart I used for the previous test on a 3rd party cart.  I had re-injected the recovered ink back into the cart.  Hence there was a small amount less ink than last time.  I also used the plastic clip with shortened needle glued into the base.  The tube that enters the pump is a very narrow rubber tube, which fits loosely into the needle inlet.  I wrapped some teflon tape around the tube to make it a tight fit.  After about 40s I had to stop because it had extracted 5ml of ink and I was not prepared for much more.  It definitely had more to offer.

I flushed the pump again and connected the OEM Grey cart that I had used in previous tests and has about 1g of ink left in the sponge.  I removed the sticky tape from over the sponge vent.  After 1.5min I stopped.  No ink had been extracted using the pump, or even entered the syringe/needle hub.  I reconnected the syringe and tried extracting ink.  In this case I did not extract ink but got a small quantity in the sringe/needle hub, which I just washed down the sink.

So in summary, the purge unit works but does not exert as much pressure as the syringe.

Bruce

I have spent a bit of time researching the best way to progress with this idea and think I have come up with a very simple workflow with very little cost outlay.

The workflow is based on a few proven concepts but is limited to use on specific Canon printers, namely the Pro100, Pro100S, Pro9000 and Pro9000 Mark II.  The workflow may apply to other Canon printers but I don’t have enough information to determine which ones.

I will post more details on what is needed when I have tested the full concept, but essentially it is just the equipment used in the previous posts re extracting the ink from the donor cart, but with a few modifications, plus some decent tape, such as aluminium tape.  Resetters are more expensive than I expected, for CLI-42 carts, so that is optional.

I am going to assume 3.2g can be extracted from a cart reported as empty by the printer.  See Reply Post #10 to see how much was extracted from my GY cart.  I have only allowed 2 carts to go to empty on my Pro-100, so the average ink used by those 2 carts was 9.67g.  The recoverable 3.2g represents 33% of usable ink in a new cart.

However, if we stop using and remove a cart when the low ink warning appears, and replace it with a new OEM cart, the removed cart would have approx 1.02g more ink to use before the “Empty” warning, than the previously mentioned 3.2g.  So typically 4.2g that can be recovered.  The 4.2g to be removed from the donor cart presents somewhere in the vicinity of 43% of usable ink in a new cart (ie. 9.67g).

 It is probably best to explain the general workflow at this point and then expand the detail.

Step 1:   When a cart gets to “Low”, it becomes a Donor, replace it with a new cart.

Step 2:  Just prior to step 3, extract ink from the Donor cart.

Step 3:  When the new cart gets below 57% remaining (ie. 43% used), the cart becomes a recipient. Remove the recipient cart temporarily replacing the Recipient cart with the Donor cart, but do not close the printer cover.

Step 4: Optionally, reset the chip in the Recipient Cart.

Step 5:  You have 10 minutes, after lifting the printer cover, to inject the donor ink, into the recipient cart, using the method proposed below, before the printer head moves back to the park position.

Step 6:  Swap the Donor and Recipient carts back and dispose of the donor cart responsibly.

I am working on the basis that each cart (except the very first) will initially be used as a recipient and when removed to become the next donor cart.  Part of the aim was to avoid the need to have heaps of empty carts hanging around for lengthy periods.

More detail and explanation of the 6 steps follows.:

Step 1 has already been discussed above.
Step 2 is intended to avoid storing the extracted ink.
Step 3 is where some of the research comes into play:  You will note on another thread I have looked at the accuracy of the Canon Ink Monitor(s).  The RUI ink monitor is more accurate and easier to evaluate.  Both ink monitors jump in 10% increments and will tend to show more ink than is present because of that fact.  This suggests that the earliest you should perform step 3 is when the ink monitor hits 50%.  You know at this stage you can fit all of the 4.2g of ink into the recipient cart.

On another forum, a member has been studying the optical ink sensor and has determined that this sensor is not activated until the ink has dropped below a certain level.  The author is not able to identify the exact point this happens but information he provided suggests to me, along with other members input, it probably happens at about the 80% empty point.  The significance of this information is that it is dangerous to refill after this has happened, without resetting the cart chip, since the “Low Ink Warning” will not occur before the cart becomes empty.  So to add a safety margin, assume it happens at 70% empty.  Hence the aim is to work in the range of 50% to 70% empty, based on the best ink monitor you have access too.  The RUI is only available if you have installed the printer as a network printer.

If you choose to use a resetter, then step 3 can be done anytime between 50% and 90% empty.  The 90% empty point coincides with the Low Ink Warning.

The reason for the temporary insertion of the Donor Cart in place of the Recipient is to avoid a purge due to a cart removal.  This was tested and found to work. You only have a total of 60s before a purge will be triggered, if no cart is detected.  The donor cart will stop the timer countdown.  Each change over should take less than 10s therefore using a total of less than 20s of the available 60s.

Step 4 is optional.  If you have CLI8 carts, the resetter is much cheaper and probably worth the cost.  If you donot use this option you cannot trust the ink monitor graphs, which will report less ink than is in the cart.  However, the Low Ink Warning is still going to work, according to information I have read.  Hence there is no danger you will run out of ink and damage the printhead.

Step 5 is where the ink is injected into the recipient cart.  The 10 minute timer (also tested) on the printer cover should be plenty.  If it looks like it may not be long enough, best to just remove the Donor cart and suffer the minor purge, otherwise, I believe, there is a risk that air could be pulled into the printhead, from the very empty Donor cart, with potential damage to the printhead.

There are several ways to fill/refill a Canon ink cartridge.  The most common method is called the Top Fill method.  It involves modifying the cart.  Another common method is called the “Durchstich” or German method.  It also requires modifying the cartridge.  Methods which do not require modifying the cartridge, use the exit port and there are different options within that method.

The method I am going to try is called the Freedom Method and the advantage is that I can use the same clip used to extract ink from the donor cart.  This method uses the exit port of the cart and involves creating a vacuum inside the cart using the syringe.  The aluminium tape mentioned above is to seal the air vent.  I will post more details when I have tested the method and hopefully confirming it’s viability for this application.  I expect it to be quick, easy and clean.  In a video I have seen of the procedure; a cart was filled from empty in about 30s, after the clip was attached and the vent sealed.  The steps above should include the sealing and unsealing of the recipient cart.

Step 6 is self explanatory.

I am awaiting delivery of a few items via post, which will allow me to start testing the Freedom Method using water in my empty Gray cart.  I then need a cart to reach 50% empty to do a full operational test.

Your method seems logical.  I just question whether anyone would do this given the time to extract the ink and inject into a new cart.  Also, didn't you leave out a step: each new cart needs to have the top ball drilled out prior to becoming the recipient?  And when you do that, you typically lose a gram or so of ink when you put the plug back in the drilled-out hole (before the pressure in the cart can equalize and prevent ink from running out the bottom).

I just wonder if there's an easier way to get at the remaining ink when a cart is tagged "empty".  For example, what would happen if you took out an "empty" cart, reset it, and put it back in?  There must be some counter that lets you use a little ink out of the sponge when the light sensor sees no ink.  So by resetting an empty, you'd think the light sensor would immediately notice there's no liquid ink and start the "low ink" counter, allowing you to draw a little more from the sponge before it is tagged empty a second time.  If it lets you use 1 or 2 grams of ink past liquid-empty, that might let you use another gram or two of ink out of the sponge just by resetting it.  Of course, the big question here is: is it safe to use more ink out of the sponge without damaging the printer due to loss of ink delivery?

Best case scenarios is: resetting an empty will cause the printer to go from "empty" to "low" on that cart and will go back to "empty" after another 1.5 to 2g of ink is used (i.e. before it is REALLY empty and damages the head).  If that's the case and it is determined that you can safely use that sponge ink, you could pull a cart the first time it is labelled empty, reset it, put a sticky "dot" or piece of tape on the top of the cart to indicate it has been "empty reset", and put it back in: run it until it says empty a second time at which point you discard the cart if it has the dot/tape on it.

In the end, even this method may have too many variables to be worth it:

(1) If 3g of ink remains on first "empty", can we be sure that resetting the empty will only cause <3g of ink to be drawn before it is marked empty again?
(2) Given (1), are we sure that drawing more ink from the sponge is enough to feed the printer and not run the head dry?

Mike

The Freedom Method does not require any modification to the cart at all. You do not need to touch the top ball.  The ink enters the cart via the Exit Port.


This essentially does the same as “Ink Monitor Override”, perhaps with one advantage and one disadvantage.  It’s a long long time since I have  overridden the ink monitor on a Canon Printer, but here is my recollection of how it works:

When the printer reports a cart as empty and you ignore that and try to print you will be prompted that the cart is empty and to continue using it is potentially damaging to the printer.  However, Canon give you the option of continuing to use the cart, by overriding the ink monitor.  When the cart was reported as empty there are several warning lights in addition to the on screen advise.  One of those is the red leds associated with the cart start flashing quickly, another is the “Resume Button” on the printer also starts flashing quickly.  The on screen advise will ask you to press the “Resume Button” if you wish to ignore all the warnings.  This action will result in the ink monitor displaying a “?” against the overridden cart, in place of the red “X’.  In addition the cart graph will be completely white, instead of showing 5% remaining, as in the case of the normal empty graph.

If you use the cart with “Ink Monitor Overridden”, it will eventually start to run out of ink, but there is no way of knowing when that will be, and when it does happen there is the potential to damage the printhead.  If you are part way through printing an A4 or A3 when ink runs out, you won’t know immediately because that part of the print is not yet in view and you really need to stop it printing ASAP.

Removing the cart and resetting is much the same as Overriding the ink monitor,except the ink monitor is not totally useless but it is misleading.  The ink monitor will start at 100% full, drop to 90% full after the 1st ml or so, then drop to 80% full after the 2nd ml or so and I suspect around about this point is where it is likely to run out of ink and you have the same problem of potential damage to the printhead.

Transferring ink from a Donor cart to a Recipient cart removes the danger of damaging the printhead and, I believe, should yield more ink than continuing to just use a cart reported as empty.

I agree that extracting the ink took a bit of effort in my initial trial, but I hope my revised equipment will improve that significantly.  Refilling is frankly “a piece of cake” (is that a globally used term) using the Freedom Method, from what I have seen and read.  I have not tried it yet though.

The workflow I described has more procedures than necessary, but I wanted to make sure it was foolproof.  eg.  It is potentially possible to remove a cart refill it and replace it within 60s.  However, I can imagine someone new to refilling could panic in the rush to beat the clock and stuff things up.

If it takes that long after a reset to recognize that the liquid tank part is still empty, that obviously won't work and will result in a damaged head.

I agree that pull-push (freedom) method looks easy but I haven't tried it either: I'm working with modified carts that fill from the top with a plug.  The freedom method does sound easy, but in my experience even the easiest (sounding) methods can get messy.  If you haven't tried it either, I would say give it a try and video it first before recommending that.  Maybe it turns out to be simple and clean, but there's also a chance that unforseen common problems can make it not worth the effort.  I'd definitely be interested in seeing a YouTube video showing all the steps.  If it is indeed easy, the video would be under 5 minutes and would be quite informative.  At a minimum, even if it is easy, there may be some important tips such as making sure you pull back far enough so you don't leave pressure in the cart and spray ink everywhere when removing the adapter, etc.

Mike