German "Durchstich" refill method for the PGI-520/CLI-521 cartridges

[Parhs]

Am i going to have problems refiling these opaque cartridges? The text wasnt printed correctly. Printer needed print head alignment! Now prints ok!

 

[ThrillaMozilla]

Thanks for your comments. I have taken most of your suggestions and edited the original.

Yes, there is a reason: it will be very difficult to put a hole in the side at a steep enough angle to allow the needle to find its way to the hole in the bottom of the dividing wall. It's sometimes a challenge even with a two-inch needle going in straight from the far end of the cartridge. Two-inch needles are not that hard to find.

Agreed, one can find the needles, although you have the difficulty of that long probe, and some people claim that you can mess up the top of the filter or the sponge around the filter. I suspect that most refillers could manage to drill a good diagonal hole. You need to start with a pilot hole part way through the wall but straight in. In some cartridges you can see the divider wall (see HP picture below), so the target should be easy enough to find. Of course, I'm speculating. I haven't tried either way yet.

I have never observed any grooves in a Canon cartridge that go all the way from top to bottom. Could you point out where you see these in one of the pictures?

This shows it pretty clearly, on a Canon cartridge. If you look closely, you can also see some internal details from the outside of an HP cartridge.
(Click to enlarge)

The recessed grooves only go half way up the dividing wall in a Canon cartridge. So it ends just below the top of the lower sponge.

It should be clear now.

You can easily overfill the sponges when top filling. It generally won't happen with the German (or as you say it, durchstich) method.

Good point. I hadn't thought of that. There's a way to avoid that problem, but there's a price.

Also, I don't understand how you can determine how much ink is in a cartridge by drawing back on the syringe.

This is now explained further.

I presume you are talking here about refilling one of those HP cartridges that is disabled by virtue of the dividing wall being inserted up-side-down, correct? How would you refill from the top? It is quite easy to refill just the sponge side of a Canon (or HP) cartridge by dripping ink onto the outlet port (with the cartridge up-side-down of course) but it will not stop when the sponges are saturated--it will merely fill up the air gap in a Canon cartridge and eventually come out the air vent. I presume the same thing will happen for an HP cartridge.

These questions are now answered above.

I would say it is nearly impossible to fill the reservoir from the outlet port, unless, of course, you introduce a hole in the reservoir or a needle in the reservoir.

No, apparently it isn't. I think the problem is controlling sponge saturation.

 

[ThrillaMozilla]

Am i going to have problems refiling these opaque cartridges? The text wasnt printed correctly. Printer needed print head alignment! Now prints ok!

Did you not understand jimbo123's post? It's not opaque. And even if it is, you can refill correctly. In my long post I describe how to determine the liquid level in an opaque cartridge.

 

[barfl2]

I tried refilling the opaque HP 564 OEM carts with variable sucess. Filling via the exit port with the excellent Intec kit works well but you only put in 4mm and is only suitable for the standard size cart. As pointed out by Pharmicist will not work with the XL version. I tried the German method but found it very difficult to get the needle through into the ink chamber. after a lot of attempts managed C/Y/M?PhotoBlack but could never get through on the large pigment black cart. I had lots of printer messages telling me using used carts etc.

eventually got fed up with all the messing about and purchased some clear refillable Carts Another problem which has been mentioned by other contributors is that you top up ! cart and the M/C does a heaed clean and wastes more ink. In fact it never seemed to stop cleaning tself. So I got rid of it and bought a Canon Pixma MP760 which is so easy to fill quiet in operation and much more economical with the ink.

I am sure the keen dedicated refillers will continue to find ways of refilling the new opaque carts, I am just happy with the old technology

 

[martin0reg]

I think ink flow and air flow is simple as that:
The saturated lower sponge seals the ink chamber from getting more AIR, therefore no ink flow from ink chamber to the outlet WITHOUT printhead sucking.

Air from sponge chamber to ink chamber - and therefore ink from ink chamber to sponge chamber - is only flowing when the lower sponge gets DEsaturated to the upper end of the grooves.
A third party cartridge without grooves will give air and ink when the sponge gets DEsaturated down to the passage.

ghwells did mention the air bubbles in a "groovy" cart appear more constantly while in a cart without grooves more abrupt.

The cartridge without sponge would act similar to this, but chambers / outlet interchanged:
http://www.youtube.com/watch?v=A7k8yKQwF6c

Refilling in another way than german/durchstich or top fill or vacuum fill I think is impossible or at least impractible.

 

[ThrillaMozilla]

Air from sponge chamber to ink chamber - and therefore ink from ink chamber to sponge chamber - is only flowing when the lower sponge gets DEsaturated to the upper end of the grooves.
A third party cartridge without grooves will give air and ink when the sponge gets DEsaturated down to the passage.

Yes, probably. I think the sponge retards the ink flow a little. In a sense it acts like a crude pressure regulator.

EDIT: Grandad35 has also observed that the sponge partly empties before the ink chamber empties. http://www.nifty-stuff.com/forum/viewtopic.php?pid=770 , post 72.

 

[ThrillaMozilla]

I had lots of printer messages telling me using used carts etc.

That's HP's fault. I even get some error messages with the non-refilled OEM cartridges. With refilled cartridges you probably need to turn the warning system off altogether, or it will pester you constantly. You can turn it off from the panel on the printer.

 

[paulcroft]

@ ThrillaMozilla

Nice spot on that full height groove, as you call it, on the BCI-6 cartridge I cut open. I hadn't noticed that. It's a very shallow recess in the cartridge wall and tapers to nothing just below the top edge of the upper sponge.

The cartridge is a genuine Canon one, not a Canon-compatible.

Something occurred to me as I was looking at the cartridge again. In its assembled state the ink chamber appears to be completely sealed at the top, in fact it would have to be or we know that ink would drain out and flood the printer. That being so, am I right in thinking that in use, and as the ink level drops, the air pressure above the ink will reduce to below atmospheric pressure?

If the pressure does drop as ink is used, how does the ink then flow from the ink chamber into the sponge chamber or is the reduction in pressure simply not enough to prevent this happening? And if I am wrong and the two pressures are identical, how does the air pressure above the ink get to be the same as the air pressure in the sponge chamber without the ink draining out of the feed hole?

Just me pondering ...

Paul

 

[l_d_allan]

ldallan: Here are the exit port caps that I use on my CLI8 cats, work very well. Check their #1916 plug for the refill port. Thr exit port caps let you store the carts side by side.
http://www.rjettek.com/catalog/product_ cts_id/469

Thanks for the info. I had some trouble following the link you provided, and didn't realize what the #469 was.

I did some more checking and now realize what you meant. I have also been impressed by the #1813 outlet port cap for covering the bottom opening. Seems Much Much better than reusing the orange cap that came with the cartridge. I have my doubts the orange twist cap is meant to be reused, as the fit is rather loose, especially compared to the #1813 cap.

So far, this newbie is also finding the #1916 plugs that came with their starter kit work well. I guess the "acid test" will be when I refill cartridges I previously filled for the first time and used the #1916 plug. Will I continue with leaks being avoided? Or not?

 

[ThrillaMozilla]

...am I right in thinking that in use, and as the ink level drops, the air pressure above the ink will reduce to below atmospheric pressure?

Yes, there's a partial vacuum. Without the sponge, the vacuum would exactly counterbalance the difference in ink height between the two chambers. This must be true because the pressure in the sponge chamber is atmospheric. (Of course, the sponge complicates this a bit.)

If the pressure does drop as ink is used, how does the ink then flow from the ink chamber into the sponge chamber or is the reduction in pressure simply not enough to prevent this happening?

Assuming the sponge chamber stays at atmospheric pressure, you can't get much ink out of the chamber unless you replace it with air. So I think most of the ink comes from the sponge at first, then once sufficient ink is drained from the sponge, air can get into the ink chamber. This is simplified a little because the sponge complicates everything.