Digital BW, The Print

Ken,

> I'm running off a set of prints for a sale this
> weekend.  Naturally, this is the time my printer
> decides to give me problems...

> using the MIS 3MK inkset in an Epson R1800...

>  started to get some banding in dark areas of the photos.
...
> I decided to drop my MIS cleaning carts in
> and run some cleaner through.
> 
> I printed about 8 copies of a dark print, until the
> page basically came out blank, then I dropped in the
> new carts.  I ran several prints, but now the banding
> is much worse and I get "overspray" in all the light
> areas of the print, including off the sides of the
> print, where this is no image.

This overspray is often caused by junk on the surface of the head.  
(In my house it's usually dog hair.)  I now use cloth "bias" tape 
soaked with Windex to pull back and forth under the head.  In the 
past I cut a strip of paper towel and folded it to make a 1/2", three 
ply strip that I'd use.  I've also just used strips of throw-away 
cloth for this purpose.  But whatever I use, I wet it with Windex 
(ammonia disolves the ink's non-water-soluble binder), lay it in the 
printer where the head goes over it, release the head (with the 
printer off -- or hit the ink load button and pull the plug), move 
the head over the strip of cloth, grab the ends of the cloth, and 
pull it back and forth such that it rubs the bottom of the head.  
After that a single cleaning cycle is usually needed and, with luck, 
the nozzle check will be fine.

 
> I did a nozzle check test page and it showed that the
> black nozzles were badly clogged.  They have never
> failed a nozzle check before, although the Epson
> colour inks do from time to time.

If the problem does not clear and you don't use color in the machine, 
the easy way is to simple switch the Eboni ink from the black to 
another spot.  Then leave cleaning fluid in the black spot for a 
while.  It'll probably eat its way through the clog after a while.  
Of course, if you use color also in the 1800 you don't have any extra 
spots for the Eboni.  Also, some proficiency with QTR may be needed 
to switch the curves from on spot to another in the QTR profiles.  I 
found that I didn't even have to re-linearize the profiles in my 
1800, but some users seem to need to re-linearize when they do this.

 
> ...  What's the proper way to use the cleaning carts? 

There is no "proper" way as far as I know.  I usually try to avoid 
too many cleaning cycles because of the ink waste and the fact that 
the service light will come on, shutting down your printer after too 
many.  So, putting a cleaning cart in just the troublesome position 
and printing that solid color through the driver or QTR makes sense 
to me.  That method, however, will not wipe junk like dog hair off 
the head.  Part of a cleaning cycle is the use of a wiper to clear 
the head.  This doesn't always work, however.  Thus my cloth strip 
under the head method.

Good luck with the clog.  I'm guessing it's junk under the head, 
because Eboni just does not clog very much.

Paul
www.PaulRoark.com