HP CIS problems - need fix, or new printers

[websnail]

Do you have any pictures? I was thinking of bypassing the bag all together and just connecting a tub right before the one way valve that goes into the pressure bulb.

I tried the whole bypassing thing myself at one point but for a whole slew of reasons (see below) you don't want to do that. Much better to just use the fill hole and use the bag as a safety valve to capture any air bubbles (a major printhead killer with the HP88) and easier to modify too.

Best thread to read on this whole topic is here:
http://www.continuousink.info/forum/viewtopic.php?t=4066

It shows the steps I went through to figure out a lot of the problems and deals with the points above nicely.

Also, on your site what does it mean not black chip dependant?

There's two types of chip when it comes to HP.

1. Dependent, where the CYM chips all take the lead from the K (black) chip. They ALL need to be used as a set and won't work if one of the chips (especially the black) is not present.

2. Independent. They store their own ink level information and will work with any other OEM chips (but not the dependent ones).

I should probably make that clearer on the site too

 

[ZenMasta]

I tried using the fill hole by simply putting the tube in the hole and sealing with hot glue but it leaked. I tried super glue to fill the leaks but it didn't seem to want to dry.

Also, the hot glue was getting too tall and it is preventing me from putting the caps on. Sounded like you have successfully used the fill hole, how did you do it?

 

[websnail]

I tried using the fill hole by simply putting the tube in the hole and sealing with hot glue but it leaked. I tried super glue to fill the leaks but it didn't seem to want to dry.

Also, the hot glue was getting too tall and it is preventing me from putting the caps on. Sounded like you have successfully used the fill hole, how did you do it?

Well my solution was to use Threaded barb elbows
(Sorry folks, link no longer available)

... and a two part super glue. I would prefer to use a flexible super glue but turns out I'm allergic which fubar'd things royally and now I get hay fever (bonus! )

I'm working on improving the approach somewhat and hot melt may end up being the solution but only if I can figure out how to fix it in place before cooling goes too far.

One thing NOT to try is silicon sealant because if you get any silicon into the ink it'll kill the printhead by blocking it so just avoid that one completely.

 

[ZenMasta]

So you screw that into the fill hole? 1/4 inch seems big but I haven't actually measured anything yet. I was thinking of just using the same glue I'd use on pvc/abs pipes for irrigation/plumbing since the hot glue/super glue didn't work today, maybe rubber cement too.

Initially I was thinking if I could find a fitting that was like a u shape so I could plug the fill hole with a barbed end and then connect the tube to the other end that is also barbed or tapered.

 

[websnail]

So you screw that into the fill hole?

I drill it out slightly with a 4.5mm drill bit but you have to be careful not to let it go too deep or you puncture the channel in the cartridge, then screw the bit in part way, apply the glue, screw down into position and then apply the fluid activator part of the glue to finalise the bond.

1/4 inch seems big but I haven't actually measured anything yet. I was thinking of just using the same glue I'd use on pvc/abs pipes for irrigation/plumbing since the hot glue/super glue didn't work today, maybe rubber cement too.

This is where all the stuff about plastics and bond energy comes into play. I'm not 100% but the plastics used for the cartridges is likely to be poly propylene which is a very low energy plastic. That means it's a b*stard to get to bond with other things. There are specialist glues but the issue there is getting them applied and screwing in the bit in time for it to bond properly... The word "nightmare" springs to mind.

That said I've not actually tried rubber cement and it's occurred to me that instead of worrying about a "bond", I should be thinking more of a "seal" so rubber cement or something similar may work. However whatever's used must not pollute the ink so it's tricky. Worth a try though.

Initially I was thinking if I could find a fitting that was like a u shape so I could plug the fill hole with a barbed end and then connect the tube to the other end that is also barbed or tapered.

The thing you have to remember is that you have to form a seal/plug and have enough space for the fitting to bend and attach to a new tube. As I'm sure you've realised the issue is with the chip holder providing limited space for it to fit over the fill hole.

I've not seen any "U" shaped fittings that do that so you may have to rethink.

Oh and one final thing.. If you do use the fitting I linked to earlier, you need to make sure the tube wall is not too thick as it can push the chip holder out of position.


Fun huh?

 

[ZenMasta]

Yeah, I really should have only tried it on one cartridge before I did it on all four and assuming it was going to work. I just figured the the hot glue would have made a good seal but once the bags got half full they started leaking.

 

[websnail]

Yeah, I really should have only tried it on one cartridge before I did it on all four and assuming it was going to work. I just figured the the hot glue would have made a good seal but once the bags got half full they started leaking.

If it's any consolation I've spent a LOT of time on those cartridges trying all sorts and gone through about 20 cartridges figuring out new ways to mess it up.

I'm still not 100% happy with things but I suspect I'm getting close.

 

[ZenMasta]

I have another idea. This is related to threading it into the fill hole. If you've ever done minor plumbing (such as fixing a shower head) you might remember using teflon tape that goes between the copper thread and your fixture. It helps create a seal between metal and plastic to prevent leaks. I might have to try that.

[edit] or if you could find a similarly sized fitting like your threaded one but metal not plastic, you could heat it up with a blow torch and thread/melt it into place. This is just another wild thought I came up with. Probably not something I really plan to try.

 

[websnail]

Hmm... might work at that.. only problem I could see is having the dexterity to get the tape in place and keeping it there because we're talking small scale and fiddly here. Interesting idea though.