German vs vacuum refilling?

[l_d_allan]

In the past, I vacuum refilled large numbers of cartridges at one time, then I switched to the German refill method, but recently, I'm looking back at vacuum refilling. Without the proper investment in vacuum equipment, I recommend the German method.

ghwellsjr,

I'd appreciate hearing more about your thoughts on the pro's and con's of vacuum refilling vs German refilling.

I'm curious if you have switched back to vacuum refilling? My impression is that vacuum refilling is a reasonable alternative if you have a lot of carts to refill, but perhaps you have devised a different technique?

 

[ghwellsjr]

The main problem with vacuum refilling is the investment in the vacuum pump and vacuum chamber. It is messy, wastes a fair amount of ink unless you are doing a very large number of cartridges, and can be a hassle cleaning the ink out of the air vent serpentine path on the top of the cartridge.

I did switch to the German method and continue to use it but I recently ran into a problem which concerns me. One of the refilled cartridges that I had reused the vinyl tape over the refill hole leaked out on the table on which it was sitting upright. It was as though there was a slight air leak in the reservoir although there was not. I concluded that the 18 guage needle opened an air path from the refill hole to the hole at the bottom of the reservoir. The tape that I used to cover the refill hole was not making a good seal since I reused it. I now do not use vinyl tape because it does not work well especially on the irregular surface. I have switched to Gorilla tape.

But the bottom line is that if you are going to use the German method, you better seal the refill hole. I know a lot of people claim they don't have any problem but how would you know if it happens inside your printer? Several of the printers I refill for were showing lots of ink in the tank but when I examined them they were empty. These were CLI-8 cartridges where the optical sensor on the bottom of the tank is ignored. If this had happened with BCI-6 cartridges, it would have immediately alerted me to the problem.

By the way, this problem didn't happen immediately, it took many weeks from the time I refilled the cartridge until it started leaking on the table. Since I refill for other people, I am very sensitive to problems of this nature.

My last several small batches of refills I did by vacuum and I'm still working on a good procedure to do that. I used to refill through the air vent port with the outlet ports sealed and the cartridge upside down. This of course fills the air vent path with ink which must be cleared out. Now I'm experimenting with refilling through the outlet port and the air vent path sealed and the cartridges right side up. I'm hoping to find a means that will prevent ink from getting into the air vent path which means the ink tank usually doesn't get completely full but that isn't necessarily a bad thing. Anyway, it is not working out consistently.

I haven't given up on the German method, I just realize all the more how important it is to seal the refill hole. I'm probably going to get a hot glue gun and use that to reseal it.

 

[pharmacist]

ghwellsjr,

I think your problem is a slight displacement of the sponge, which causes the ink to escape by capillary action taking the route of the least resistance. You should make the refill hole as small as possible, jus tiny enough for the needle to be able to enter the cartridge without any considerable resistance. You could give the cartridges a few ticks on a wooden rod, so the sponge can be realigned along the bottom of the cartridge.

 

[ghwellsjr]

I'll remove the tape, make sure it continues to leak and then see if whacking it fixes the problem. I make my hole just barely large enough for the 18 gauge needle and I make it as low down as possible.

 

[ThrillaMozilla]

The reason for running the needle under the sponge, of course, is so you can hit that hole in the wall, which is quite small in some cartridges. If you make the fill hole higher (above the top of the opening between chambers) and go THROUGH the sponge, I think it is less likely to leak, and it cannot leak inside the printer if the vent is open. In HP564 cartridges the opening between walls is only around 2 mm high, but it does not even extend all the way to the bottom, so hitting it by going through the sponge is problematic. Going under the sponge (I call it the unterstich method) makes the opening an easier target, but you risk making a gap under the sponge.


EDIT: I wrote that "it cannot leak inside the printer if the vent is open." I meant it can't leak inside the printer unless the sponge is oversaturated.


A gap under the sponge could also cause a leak in the ink exit port, I think.

If you try to fill through the exit port (with the vent closed), I think you should fill with the ink chamber down and the sponge chamber up. Then you can alternately fill and draw air out. By drawing back on the syringe, you can even start with a vacuum if you wish, and this would remove some old ink. You should be able to saturate even a dry the sponge pretty well that way as well, getting rid of air. The hard parts are (1) avoiding ink in the vent and (2) getting correct saturation. It might be good to withdraw a little ink from the sponge as a last step.

I saw this demonstrated with a transparent cartridge, but I cannot find the video. I am planning to try this in the near future with water on a used cartridge.

 

[l_d_allan]

The main problem with vacuum refilling is the investment in the vacuum pump and vacuum chamber. It is messy, wastes a fair amount of ink unless you are doing a very large number of cartridges, and can be a hassle cleaning the ink out of the air vent serpentine path on the top of the cartridge.

ghwellsgr,

I'm wondering if a variant of vacuum refilling might work, by combining with a technique described as an alternative approach to purging.

(Note: haven't tried the following ... just a 'thought experiment')
* Ink would be placed in a bottle cap or flat bottom glass cup
* Clean the cart and place it in the bottle cap so the outlet port filter was in the ink.
* Tilted down naturally so the vent hole was above the inlet port
* Plug inlet port hole with RJetTek #1813 rubber plug (or equivalent silicon plug)
* Seal top vent hole with electrical / vinyl tape
* Insert 20 ml syringe with hypodermic needle into the reservoir by piercing the inlet port through the #1813 rubber plug.
* Draw syringe back to create partial vacuum within cart
* Ink drawn into cart through outlet port
* Withdraw syringe/needle out of #1813 plug, which naturally seals when needle isn't there
* Either replace pierced #1813 plug with unpiereced plug, or seal pierced #1813 plug with electrical / vinyl tape
* Unseal top vent hole
* Clean bottom of cart
* Use something like #1916 outlet cap or original orange outlet cap with rubber band to seal outlet port.

Some caveats:
* Unclear whether enough negative pressure would happen to suction much ink into cart
* There would be excess ink left over in the cap / cup, so you'd probably want to have several carts of the same color to do
* Residual ink after filling several carts might be contaminated and perhaps shouldn't be returned to storage bottle?
* Cart sitting in ink with syringe would be 'top heavy' and prone to falling over into cap / cup unless there was something to support it in place
* Might take several 'pulls' of the syringe plunger.
* Not clear if excess would end up in vent hole serpentine maze (probably not good) or drawn up within syringe (probably ok)
* Might be defeating the purpose of the outlet port filter, as impurities and/or grit could be left on the outside of the filter
* Could be pretty slow, if it worked at all.

The next time I'm doing some refilling, I may give the above a try with an excess oem cart I use for experimenting, and using colored water.

So far, I'm satisfied with using the 'traditional top refilling method', and am not inclined to actually try the above with ink. I'm curious if someone tries it and whether it would work. And perhaps refinements to improve?

Suggestions / refinements / problems / other feedback for the above appreciated. It's not a technique I'm advocating, just curious if it would work.

 

[ghwellsjr]

If you are going to poke a needle through the plug on the top of the reservoir, why not just inject ink into the reservoir. Residual ink might com out of the outlet but this might be minimized if you hold the cartridge upside down, just like when refilling with the German method.

The whole idea of vacuum refilling is to not have to compromise the cartridge in any way by poking refill holes in it so if you going to poke a hole in the top, why not just do the traditional top refill technique? Also, with vacuum refilling in a chamber, you can refill several cartridges simultaneously.