#1: Canon CIS: Specific problem(s) and solution(s) Author: Martin, Location: South Yorkshire, UKPosted: Thu Jul 13, 2006 11:27 pm — I'll start this thread off with an issue which I've notices is particularly prevelant on the Canon systems and that's the issue of maintaining an air tight seal between the cartridge exit port and the ink receiver/rubber grommit in the printhead.
In the Epson printers this issue is limited by the fact that the ink receiver protrudes up into the Epson cartridges which have a rubber sleeve which seals around the receiver and stops air seepage. This is not the same on the Canons.
The Canon printer design is less worried about air seeping in because the seal is "good enough" when it comes to normal cartridge operation but in a CIS the seal needs to be completely air tight so the way the Canons work is prone to problems. You can hit any number of problems:
Cartridge exit port can have a small nick in the plastic side that could allow air in
The rubber grommet surrounding the ink receiver may be damaged
There may be insufficient pressure on the cartridge allowing it to ride up
... and more
To date I've managed to build five seperate CIS kits for the iP4000, MP750, MP500 and the iP4200 and in most cases I don't suffer too many problems but some ways to resolve these problems (if they occur) include:
Cartridge port imperfections
This required some seriously ingenious work.. I partially sanded the edge to flatten the cartridge and get out the nick (it was luckily small). I then sealed the port using some "self fusing silicon tape" sourced from B&Q (DIY store in the UK) which was held in place using some electricians tape. I ended up putting two layers on to be sure.. then punching a small hole in the tape so ink could flow out. This seemed to seal any imperfections in the cartridge port and stopped air leakage.
Damaged grommet
This wasn't an issue in my case but if you have a damaged grommet when you purchase the printhead then you need to send it back for warranty replacement or try and source a replacement. You could try using the silicon tape as above however it's not easy to cut the hole for the whole thing to slip over the ink receiver post.
Cartridge rise
This is the most common issue.. Cartridges in Canons always ride up, especially the black pigment PCI-3, PGI-5, etc.. black cartridges (the big ones with the big ports). My solution has been to either use some tubing or as someone suggested, some kitchen sponge (from a sponge scourer) cut to size and placed underneath the printhead locking bar to help hold the cartridges down with some pressure.
Note: You need to be careful to avoid the locking bar/lever from being forced to pop up as this obviously will jam the print carriage unit.. Experimentation required.
... and more..
... well for other stuff, we'll just have to see...
All in all the key is to ensure you have a good seal between the cartridge and the receiver.. it's possible that better ways to deal with some of these issues will arise with time but hopefully the stuff above gives some early pointers to keep an eye for.
