Clogged Canon print head

[turbguy]

I would consider the "caverns" to be a potential impediment to supplying ink to the full line of nozzles, IF an air bubble gets trapped in them.

Wayne

 

[mikling]

It could be that Canon found a superior adhesive to use compared to what I taken apart. The head I dissected had the top plate come off cleanly This is different from the one you show and experiencing. The one I used is off an i860 so it's pretty old.

Maybe someone knows a Canon engineer involved in the printhead design somewhere?

 

[Grandad35]

The head I dissected had the top plate come off cleanly This is different from the one you show and experiencing. The one I used is off an i860 so it's pretty old.

As with your experience, the print head that was dissected earlier in this thread also popped apart cleanly at the adhesive line. It didn't just fall apart, but the failure point was always an adhesive failure at the surface, never a cohesive failure within the nozzles like that shown on the i9900.

 

[websnail]

Just a thought on the damage from a few pages back... Would an ultrasonic cleaner be a candidate?

 

[Grandad35]

The saga continues....

I offered to try this cleaning technique on someone else's print head after they already purchased a new print head to fix their problem. The first screw came out normally, but the second screw just wouldn't come loose. Long story short - the second screw had a left handed thread - see the photo below. The lesson is that if a screw doesn't want to come loose, try rotating it in the reverse direction before stripping out the head like I did. As you can see, getting the stripped screw out wasn't pretty (or easy).

1/14/13 Edit
BTW - I just noticed that the left hand screw has 2 starts instead of the normal 1 start. Reason?

9/4/14 Edit
The left hand screw was on the left side looking at the bottom of the print head with the circuit board on the bottom.

 

[Nifty]

Wow! I HATE stuff that is reverse threaded!!! If you don't know the thread direction you never always have to worry that you're possibly tightening things beyond belief.

 

[fotofreek]

consider the confusion with L/H lug nuts or bolts when the owner of some pre 1970 Chrysler products have to change a flat in the dark on the shoulder of a busy highway One side R/H and the other L/H! Many trucks came that way as well. As I recall, some MG's and Indy cars had L/H on one side and R/H as well.

 

[Grandad35]

But at least there was a reason for the left-hand threads on the driver side - see this link (esp. pages 2/3) for an explanation. There is no reason for this on print heads, other than to stop people from taking them apart.

 

[The Hat]

other than to stop people from taking them apart.

Wouldnt that be in the owners best interest then ? ..

 

[PeterBJ]

I wonder when Canon started using this technique? So what was the printer model, printhead type and ink cartridge family?

I wonder what is the purpose of this? If customers ruin the printhead and possibly the printer too, they might buy a new printer and so also at least one set of OEM cartridges, probably the new starter cartridges, so they will also have to buy a set of normal cartridges after the starter cartridges are empty.