I Hate My Canon

[mikling]

Leaving the top totally white can be tricky as it sometimes can lead to underfilling. Underfilling is something that must be considered today. Over the generations of printers, I have noticed that Canon has changed the logic of how the optical sensor works. If a cart is underfilled too much, what happens is that that he cart can be totally drained before the optical sensor kicks in to warn of a low cart but this is an extreme situation.

From the nominal testing I have been able to perform, the sensor will work properly especially on the newer printers only if the sensor detects an out of ink situation within a chip counter range. That is to say, if the chip is full and the sensor senses out of ink it will not flag a situation. Maybe, the sensor is not even turned on till the chip reaches a certain level! What is clear though is that the optical sensor and cartridge chips work together in a certain algorithm that is yet to be defined by people like us.

The obscuring of the ink sponge levels also points out that Canon has also changed when it wants to flag a low ink condition and what it deems low is not necessarily what we view as low.

What is also known is that suppose the sensor detects the reservoir is empty but the chip count is on the high side, the printer will decrement the chip in one swoop so it coincides with what should be and ink level and chip is re-syncronized from low towards empty. This makes sense because once the sensor detects no ink in the resevoir, it begins a countdown to the empty stage in a precise fashion because the situation becomes risky lest the printer lose count of the ink left and damage the printhead. You will also now notice how the printer will then seem to operate by takings its time before it starts to print.

 

[PeterBJ]

.....What is also known is that suppose the sensor detects the reservoir is empty but the chip count is on the high side, the printer will decrement the chip in one swoop so it coincides with what should be and ink level and chip is re-syncronized from low towards empty. This makes sense because once the sensor detects no ink in the resevoir, it begins a countdown to the empty stage in a precise fashion because the situation becomes risky lest the printer lose count of the ink left and damage the printhead. You will also now notice how the printer will then seem to operate by takings its time before it starts to print.

So a cartridge flagged low on ink can slow down printing by increasing the time from data are received till printing actually starts? Do you have more info about this?

 

[mikling]

So a cartridge flagged low on ink can slow down printing by increasing the time from data are received till printing actually starts? Do you have more info about this?

You will notice the extra primings of the printhead performed by the printer to ensure that ink is in the printhead, nothing about data transferred.

 

[Grandad35]

@mikling
Those are a great set of videos. A few comments:

• At 5:30 in video #3, you call the missing ink "foam". I prefer to think of it as air pockets in the "felt" (see this post), where the ink no longer wets out to the inside of the cartridge case/felt boundary (where you can see the air pockets) or inside the felt itself (where you can't see the air). As long as there is an "ink link" (a term that you coined) in the middle of the felt, ink will flow, so air pockets on the surface aren't necessarily terminal.
  
• I always see at least a little air in the lower sponge after the initial use, but the carts work perfectly in the printer as long as they pass the "drip test".
• At 1:40 in video #2, you show the initial ink absorption rate after purging, and it is similar to what I have experienced on carts that have not been "conditioned". With a conditioned cart, the initial absorption rate is much faster.
• With unconditioned carts, I have noted a very slow initial fill at times, but I have not experienced the same problem with conditioned carts.
• The real reason that I started conditioning my carts is that the PM and PC would sometimes fail the drip test after the 1st refill. With conditioned carts, I no longer have a problem unless I let a cart get too empty.
• My theory is that the small amount of residual glycerine that is left in the carts after drying coats the fibers in the felt and changes its surface energy so that the ink wets out better, allowing ink to better refill the air pockets in the felt.
  
• Another old post on the same subject.

@martin0reg
I have been filling my carts to the top for quite some time, and do not have a problem as long as I make sure that there is no "free ink" above the top felt by blowing into the vent port. The benefit is that the carts hold more ink and don't need to be refilled as often. YMMV

 

[mrelmo]

OK very interesting, so is there a way to eliminate the "foam" or air pockets in the sponge, flushing and then drying pulls all the liquid out thus leaving a sponge filled with air

 

[Grandad35]

I assume that you are referring to the paradox that we eliminate air from the ink in the felt by first completely filling the felt with air. I think that I understand why the conditioning solution helps, but I am not expert enough to write an explanation that would stand up to close scrutiny. To wet out, a liquid must have a surface tension less than the surface energy of the solid that it contacts. I will leave it to others to expand on the details of what happens when a cart is filled.

Values for the surface tension of some liquids and the felt are:
Material Surface tension/surface energy
Water 73
Printer ink 32-40
Glycerine 63
Alcohol 22-23
Polypropylene 31

A number if years ago I experimented with using vacuum to refill the carts, and it did a good job of eliminating the air pockets in the felt, but it was not easy or fast, so it was abandoned. Several years later, ghwellsjr developed the "Freedom refill" method, and this appears to be a better solution for pseudo-vacuum refilling. You might want to give his method a try.

 

[martin0reg]

Thanks for the info... but regarding the two (!) sponges I'm pretty sure that the upper has other properties and normally will not suck as much and as quick as the lower. Even when both are filled to the top, the lower looks slightly darker
So I'm still thinking that the level of saturation after refilling should not rise to the top - because the upper is mainly for air exchange and therfor made of a more repellent material

 

[The Hat]

Nine times out of ten when I refill a cartridges it usually saturates the upper sponge area and to date it has not caused any ink problems while using them, so I can live with that.
P.S. O' and I love my Canon printers..

 

[martin0reg]

Well if you are refilling from the top, the ink may fill the upper sponge, but it won't rise up into the air vent. So everythings fine, while printing the ink of the upper sponge will sink down in the lower very soon, resulting in what I assume is the normal "state of saturation"...
But if you are refilling german, this is what happens to me quite frequently: while injecting the ink into the reservoir, there could be an unwanted "ink link" from the tip of the needle (which is very near the passage, you can't push it deeper because of the prism) to the sponge. So the sponge begins to suck while you have injected only a small amount. Now if I continue injecting there may be some pressure (refilling german = refilling a intact, sealed cart) and that results in ink rising up into the air vent before I could fill the reservoir.. this is really annoying after havin flushed and dried and poked the OEM cart.
PS: having learned a new acronym: ...YMMV...

 

[The Hat]

@martin0reg, the German method didn’t work very well in my capable hands either, that’s way I switched to the top fill method, it works 99% of the time..

P.S. the German method is not very user friendly when refilling the small cartridges..