Evaluating Service Mode Nozzle Pattern on Canon 8300

[deanwork]

I just printed out the service pattern on the IPF 8300 for the first time.

All the blocks are perfect on the standard nozzle check.

Trying to learn how to evaluate it.

In service mode check all looks the same as the regular nozzle pattern except the following.

1. In the middle bars all is normal except for three tiny white spots ( lines missing) on the far gray block and none missing on identical block beside it. I assume this is the PK channel.

2. In that same center row all is perfect except for one tiny missing line in the left Magenta block.

3. In the bottom row the right blue block has two little lines missing.

All my output is perfectly normal . My head counts are 600,000 dots on one head and 450,000 dots on the other head.

So what is this telling me about my overall heads condition? Should I do a cleaning or leave it alone?
I'm not printing a lot on this machine right now. It has sort of been put into the backup printer mode these days. I has always remained plugged in and turned on. I don't remember the last time I heard it do a head cleaning. 90% of the media running through it is PK.

Thanks, John

[Landscapes]

Given how much you have already printed, I think your nozzle pattern sounds very very good.  A few missing nozzles is exactly what you should have since the idea is that when a few die, they are remapped to other good ones.  My printhead died at about 450,000 Mdots, but it was used for over 2 years.  (its a 6400, so gets a bit less usage than the 44" model since the prints will naturally be smaller).  I've also head printheads in the past on a 6100 that has a bunch of missing nozzles all in one area, maybe due to a head strike, and it continued to work just fine.

On this 6400, just before I needed new heads, I had easily 20 nozzles missing in each color, and it would run nozzle checks after a print quite often.  You get into this cycle of forced cleans and nozzles checks just before the head dies.

I would not bother with a clean at all if it doesn't want you to do one.  Its expected that some nozzles will be totally clogged and never work again.

[deanwork]

Thank you for the observation.

I was surprised that they looked so clean as well after two years one one head and nearly that long on the other with a lot of material of all kinds going through it. I was going to scan the nozzle pattern and post it but didn't think anyone could even see the tiny lines that were missing.

 Only after a really big job does it do any cleanings and then very short ones if any. Course it is plugged in and on 24/7 and that has worked very well for me. If I can get another few months without replacing them I'll be very happy. I do believe that head strikes can be the death of these heads and I avoid any media that would cause them. I've been down that road. Also my gut feeling is that they have improved the quality control on the heads.

Given how much you have already printed, I think your nozzle pattern sounds very very good.  A few missing nozzles is exactly what you should have since the idea is that when a few die, they are remapped to other good ones.  My printhead died at about 450,000 Mdots, but it was used for over 2 years.  (its a 6400, so gets a bit less usage than the 44" model since the prints will naturally be smaller).  I've also head printheads in the past on a 6100 that has a bunch of missing nozzles all in one area, maybe due to a head strike, and it continued to work just fine.

On this 6400, just before I needed new heads, I had easily 20 nozzles missing in each color, and it would run nozzle checks after a print quite often.  You get into this cycle of forced cleans and nozzles checks just before the head dies.

I would not bother with a clean at all if it doesn't want you to do one.  Its expected that some nozzles will be totally clogged and never work again.

[Landscapes]

Yes, i do think the heads on the 6400 are better than on the 6100 I had, but since both heads usually go within weeks of eachother, switching over to just one head design and making it cheaper was probably a good move on Canon's part.  Mind the though, those Hp3200's with their very cheap heads is also quite appealing.  I have a feeling though that in your case, when it does go downhill, it will go downhill quick.  That is what I seem to remember.  For the longest time I thought wow, this head looks so good after more than a year with hardly any clogs, but then i think within just a few months I saw more clogs, more cleanings, and it was toast.

My complaint was that for me, which seems to happen to other people as well, all of a sudden the printer decides it wants a new head and it initiates the purge cycle all by itself.  If I didn't have a new one on hand, I don't know what I would do because there is no way to stop it once it starts, unless maybe pulling the plug, but I"m not sure if the head is parked where it needs to be.  And once it finishes, the head already moves to the middle.  Some people do get error messages first, but when the printer decides its had enough, it should at least tell you without starting the spilling cycle.  At least that's what happened to me this last time a few months ago on my 6400.  So just a heads up.

[stockjock]

I just printed out the service pattern on the IPF 8300 for the first time.

All the blocks are perfect on the standard nozzle check.

Trying to learn how to evaluate it.

In service mode check all looks the same as the regular nozzle pattern except the following.

1. In the middle bars all is normal except for three tiny white spots ( lines missing) on the far gray block and none missing on identical block beside it. I assume this is the PK channel.

2. In that same center row all is perfect except for one tiny missing line in the left Magenta block.

3. In the bottom row the right blue block has two little lines missing.

All my output is perfectly normal . My head counts are 600,000 dots on one head and 450,000 dots on the other head.

So what is this telling me about my overall heads condition? Should I do a cleaning or leave it alone?
I'm not printing a lot on this machine right now. It has sort of been put into the backup printer mode these days. I has always remained plugged in and turned on. I don't remember the last time I heard it do a head cleaning. 90% of the media running through it is PK.

Thanks, John

I have had to replace two heads on my Canon iPF8400 in just under three years.  The Service Mode Nozzle Check didn't provide any indication that the head was going to need to be replaced.  When I see more than a few missing segments in the Nozzle Check I will run a head cleaning A since it uses relatively little ink.  I only run it once.  I do try to have the printer print every 3 days using Windows Task Scheduler.   Since some people seem to believe that continuing to use a head after the error warnings by running multiple cleaning cycles can risk burning out the very expensive main circuit board I replace the head when I get error messages more than a 2-3x in a row.  I'm not happy that the heads are a consumable that doesn't relate directly to the amount of usage but I'm also not surprised since I knew that buying the printer. I have been very pleased by how cost effective the iPF8400 is when it comes to total ink usage.