BASICS of understanding Canon Carts and Long Term Storage

[The Hat]

Nope guys, but keep them coming.

I think @mikling explained this long time ago.

He did give a good explanation of the air vents and so have others, but not these prongs ? they’re doing something completely different...

 

[Redbrickman]

Maybe be part of the sensor mechanism then?

 

[palombian]

Something to regulate the ink absorption in the sponge ?
In a genuine Canon cart the upper 2-3 mm of the sponge stays white, why ?

 

[Tin Ho]

My 2 cents...

If the sponge were fully saturated with ink it would be like a piece of kitchen sponge fully soaked with water. A fully soaked sponge will drip water until a significant portion of it is emptied.

You don't want that to happen to the sponge in a Canon cartridge. You will have ink leaking out of the print head. In a more technical term the sponge needs to keep a negative pressure to keep the ink from leaking out of the print head. That negative pressure needs to be just right to overcome the capillary force too keep ink from leaking but not too much to keep the print head from printing. This is kind of important and for this importance you don't want to use after market cartridges. But some aftermarket cartridges do work just fine.

I believe this was discussed on this forum many years ago. It is good to remind ourselves again how it works.

 

[PeterBJ]

I think that the sponge would not work properly if the sponge filled the sponge compartment 100%, so the plastic prongs are spacers that allows air to enter the top of the sponge. Notice that a tri-colour HP cartridge also uses spacers to prevent the top of the sponges from touching the lid:

 

[The Hat]

I’ll let this question or conundrum, which ever suites, run on a bit longer, before I give my theory on it, and my answer can also be contradicted if someone can come up with an even better answer...

 

[Grazer5]

Well, I know what I do and use isn't what's considered normal ( 15 Pro-100's ), but over the years since the Pro-100 came out we have been refilling carts. Both OEM and aftermarket. The OEM carts will always need to be flushed out and dried at some point because the printers create a wall of bubbles in that channel and thus the ink will not flow properly. But only if you let the carts go empty, they last ten times longer if you refill when there is about 3 or 4mm of ink left in the reservoir.
As long as your plug is sealed well, there won't be any problems how full the cart is. We've been buying a lot of carts from China and they've been working very well, almost never plug up because they don't have that Serpentine channel.

 

[mikling]

The serpentine referred to is on the top of the cartridge. Since you are a production shop, the serpentine does not affect you at all. You need not worry about drying issues. The serpentine you refer to is not the serpentine it is an ink feed channel that Canon added after they produced cartridges without it initially the BCI-6 era. You will find BCI-6 carts with and without the ink feed channel. I have postulated before that this addition was to ensure ink flow in very heavy demand situations like cleaning or deep cleaning. It is worth wondering why Canon added this channel when they initially did not have it in their initial mold and retained it thereafter to this day. There must be a purpose.

The storage issues has to do with Temperature and barometric pressure fluctuations and relative humidity effects. The dynamics of what happens during rest during these fluctuations. This would only affect printers with very light use and with printers stored over a period of time. Again nothing that production machines would encounter in a significant way.

Aftermarket carts do not have the serpentine because it is expensive to incorporate in manufacture and keep working properly. But a purpose it does serve especially for light users.

See video
https://www.youtube.com/watch?v=nTEwj5tljhg that curved pathway is the serpentine.

 

[The Hat]

I asked this question some time ago and no one has come up with a reasonable answer for their existence, so here goes.

I reckon these prongs are essential to insure the cartridge can always breed freely, in whichever environment they are working in, they prevent the build-up any condensation that could potentially block their very elaborate serpentine path.

They increase the inside surface area of the cartridge top many times and this allows the moisture to be detained easier with little or no loss and where it can be return to the sponge later, and I reckon this is all down to these silly little prongs...