Mike Chaney's Tech Corner

Hey guys,

I've been having problems with nozzle clogging, I don't print a huge amount at the moment so I realise that's the price I pay. The nozzle checks usually pick up any clogs fine but on a number of occasions I've left the printer running and come back to find a ruined print with a missing colour or severe banding and then I'm told about the nozzle clogs afterwards as if I couldn't work it out for myself. So, I want to create a colour bar so I can print that before I do anything else or maybe add it on the bottom of prints for diagnostics or to keep an eye out for bad inks etc.

Anyway, problem is I'm not sure what the colour values would be. I'm running an epson 7900 which has C, LC, M, LM, Y, K, LK, LLK and an additional Orange and Green. I'm guessing that the Light Cyan and Magenta are 50%, the green and orange are 5050 mixes of CY and MY and that the Light Ks are 50% and 25% something like that. Anyone know if this is a fair guess or the exact values?

My aim is that every ink colour prints (or not if there's a problem), would this work or would I be better off having a series of different gradients, I only want it to be an inch or so up to 24" wide so I don't want to make it too complicated though.

Thanks in advance.

Jamie

Simply go into the driver and click on Properties, then Utility tab, then nozzle check.
You do this on plain paper and it is small but noteworthy.
Do this before every print session if you don't print often.

Fred

Hi Jamie,

It is not just nozzle blocks, but air in the feed tubes, too. You will be unlikely to be able to find a colour that will fire a particular nozzle, since you will have to take into account the icc profiling, etc. You'd need to write your own driver for that  :(.  I'm thinking that colour gradients may be the best option, hopefully you will see the banding. imho, the manual nozzle check/clean cycle works better than the auto method. I do not think merely printing a particular colour to work the air through will work, since the cleaning cycle uses a vacuum pump to suck the air/ink through. It is debatable whether it is better to leave the printer powered on, or off, between print sessions. If you can put a wet sponge/tray of water in the machine, and cover the machine with a polythene sheet, thus increasing the humidity in its vicinity will help, but not recommended if you forget to remove it before printing  :D.

Unfortunately the cleaning cycle does not work on individual colour nozzles, hence the ink wastage. Of course, if you were to get third party dye inks, then that solves the blocking situation, (but not the air locks)

Best wishes,

Ray

Cheers Fred,

Sorry, I forgot to mention that I'd used the nozzle check but I wanted to create something that was easier to see. The yellow for example is almost non existent in the thin lines that it prints. Funny though, hadn't even occurred to me to use cheap plain paper for nozzle checks, blinding tip!

Jamie

Thanks Ray,

That makes sense about the individual inks and icc issue, I'll give the gradients a whirl. It's not a huge issue, just something that I have to keep an eye on. I read somewhere about getting a humidifier and I assumed that they meant dehumidifier as I wasn't aware that such a thing existed but that makes sense now. It has been very hot and dry (and extremely rainy of course and then hot and dry again). I'll maybe give the sponge trick a go if it starts to become more of an issue.

Cheers again.

Jamie