Photocopier - paper scratches on the OPC

The ps voltage was a bit high but not enough to push the corona voltage from
5.55KV to over 8KV. The preset only varied it a few hundred volts. Put a
dropper in line and its now 5.8KV and working , subjectively, just as
before - lines on the paper image. But these lines are no longer "burned"
onto the OCD. Previously if you removed the corona housing and wire, then
the lines still emerged onto the paper for a number of runs because of a
build up on the OCD, that failed to clean off with AC and wiper blade.
Now if you remove the corona the next output is plain white so the cleaning
process can now cope with it.
I tried changing the corona housing to a spare one but the lines are in
exactly the same place. It is difficult convincing myself that the toner
lies in fine lines on the OCD as there is no obvious repeat, coincident with
the lines on the paper. There are hundreds of such fine lines with nothing
making the most persistently tranferrd ones stand out.
If the following makes no difference I will try the earlier OCD that worked
fine but the original owner managed to scratch numerous deep lines axial to
the drum so produced heavy black lines obscuring the image. If the lines
stay in the same position then it will be a total mystery as I've cleaned
,twice now, all surfaces near the OCD path. I should have said these
present lines are so fine they are just intrusive rather than blocking
information.

Going back to my original thinking, as this all started about coincident
with forced change of toner supplier. I made up a test batch of some of the
toner mixed about 2 :3 of charcoal sieved down to 75 microns, the thinking
is it would dilurte an excess of oil/styrene. It takes a while for this to
work through the feed system but so far the ratio of blackness of wanted
image to tram lines has improved, I think. I can get hold of styrene and
have plenty of silicone oil but how do you mix 98 percent sieved charcoal
with 2 percent or so of liquids without clumping? At this rate I may as well
try formulating my own toner . My set of old brass lab sieves go down to 75
micron, any ideas for a source of mesh of order 30 or 40 micron?
 
N_Cook wrote:
The ps voltage was a bit high but not enough to push the corona voltage from
5.55KV to over 8KV. The preset only varied it a few hundred volts. Put a
dropper in line and its now 5.8KV and working , subjectively, just as
before - lines on the paper image. But these lines are no longer "burned"
onto the OCD. Previously if you removed the corona housing and wire, then
the lines still emerged onto the paper for a number of runs because of a
build up on the OCD, that failed to clean off with AC and wiper blade.
Now if you remove the corona the next output is plain white so the cleaning
process can now cope with it.
I tried changing the corona housing to a spare one but the lines are in
exactly the same place. It is difficult convincing myself that the toner
lies in fine lines on the OCD as there is no obvious repeat, coincident with
the lines on the paper. There are hundreds of such fine lines with nothing
making the most persistently tranferrd ones stand out.
If the following makes no difference I will try the earlier OCD that worked
fine but the original owner managed to scratch numerous deep lines axial to
the drum so produced heavy black lines obscuring the image. If the lines
stay in the same position then it will be a total mystery as I've cleaned
,twice now, all surfaces near the OCD path. I should have said these
present lines are so fine they are just intrusive rather than blocking
information.

Going back to my original thinking, as this all started about coincident
with forced change of toner supplier. I made up a test batch of some of the
toner mixed about 2 :3 of charcoal sieved down to 75 microns, the thinking
is it would dilurte an excess of oil/styrene. It takes a while for this to
work through the feed system but so far the ratio of blackness of wanted
image to tram lines has improved, I think. I can get hold of styrene and
have plenty of silicone oil but how do you mix 98 percent sieved charcoal
with 2 percent or so of liquids without clumping? At this rate I may as well
try formulating my own toner . My set of old brass lab sieves go down to 75
micron, any ideas for a source of mesh of order 30 or 40 micron?
Click to expand...
Jesus. You're sure trying to do this the hard way!

Have you cleaned the laser module window, & tried swapping out the
cartridge?

--
W
. | ,. w , "Some people are alive only because
\|/ \|/ it is illegal to kill them." Perna condita delenda est
---^----^---------------------------------------------------------------
 
Bob Larter <bobbylarter@gmail.com> wrote in message
news:h1cn9s$8gt$1@blackhelicopter.databasix.com...
N_Cook wrote:
The ps voltage was a bit high but not enough to push the corona voltage
from
5.55KV to over 8KV. The preset only varied it a few hundred volts. Put a
dropper in line and its now 5.8KV and working , subjectively, just as
before - lines on the paper image. But these lines are no longer
"burned"
onto the OCD. Previously if you removed the corona housing and wire,
then
the lines still emerged onto the paper for a number of runs because of a
build up on the OCD, that failed to clean off with AC and wiper blade.
Now if you remove the corona the next output is plain white so the
cleaning
process can now cope with it.
I tried changing the corona housing to a spare one but the lines are in
exactly the same place. It is difficult convincing myself that the toner
lies in fine lines on the OCD as there is no obvious repeat, coincident
with
the lines on the paper. There are hundreds of such fine lines with
nothing
making the most persistently tranferrd ones stand out.
If the following makes no difference I will try the earlier OCD that
worked
fine but the original owner managed to scratch numerous deep lines axial
to
the drum so produced heavy black lines obscuring the image. If the lines
stay in the same position then it will be a total mystery as I've
cleaned
,twice now, all surfaces near the OCD path. I should have said these
present lines are so fine they are just intrusive rather than blocking
information.

Going back to my original thinking, as this all started about coincident
with forced change of toner supplier. I made up a test batch of some of
the
toner mixed about 2 :3 of charcoal sieved down to 75 microns, the
thinking
is it would dilurte an excess of oil/styrene. It takes a while for this
to
work through the feed system but so far the ratio of blackness of wanted
image to tram lines has improved, I think. I can get hold of styrene and
have plenty of silicone oil but how do you mix 98 percent sieved
charcoal
with 2 percent or so of liquids without clumping? At this rate I may as
well
try formulating my own toner . My set of old brass lab sieves go down to
75
micron, any ideas for a source of mesh of order 30 or 40 micron?

Jesus. You're sure trying to do this the hard way!

Have you cleaned the laser module window, & tried swapping out the
cartridge?

--
W
. | ,. w , "Some people are alive only because
\|/ \|/ it is illegal to kill them." Perna condita delenda est
---^----^---------------------------------------------------------------
Click to expand...


This is conventional copier with document glass and toner hopper feed. The
same problem must apply to cartridge/laser systems for when the original
specified cartridges are no longer available and supposed replacement
equivalents are not equivalent. Its just that the process (whatever it is)
is otherwise going on , unseen , inside the cartridge.
 
I tried the original OCD with the deep scratch lines axial to the drum and
there is not the slightest hint of any of the thousands of paper scratch
lines on the original, coming through to the paper, just the deep
imperfections coming through. That is old OCD with the current toner
produces a good black image with no tramlines.
I'm wondering if too high a volts/mm in the active layer, from the corona
wire being too high a voltage can cause damage. Somehow in conjunction with
very fine scratches , give a concentrated charge distribution and very
locally damage the germanium or cadmium sulphide or whatever the active
layer is. With the problem OCD outside the machine I gave it a very close
inspection and I can still not see any correlation between the paper scratch
lines that cause tramline output and any of the thousands oif other possible
ones.

It is a continuum thing. If more toner is allowed through then more and more
tramlines appear. I could understand it if some bits of hair conducted
straight from corona to OCD to cause a few permanently affected rings but
not this situation.
 
N_Cook wrote:
Bob Larter <bobbylarter@gmail.com> wrote in message
news:h1cn9s$8gt$1@blackhelicopter.databasix.com...
N_Cook wrote:
The ps voltage was a bit high but not enough to push the corona voltage
from
5.55KV to over 8KV. The preset only varied it a few hundred volts. Put a
dropper in line and its now 5.8KV and working , subjectively, just as
before - lines on the paper image. But these lines are no longer
"burned"
onto the OCD. Previously if you removed the corona housing and wire,
then
the lines still emerged onto the paper for a number of runs because of a
build up on the OCD, that failed to clean off with AC and wiper blade.
Now if you remove the corona the next output is plain white so the
cleaning
process can now cope with it.
I tried changing the corona housing to a spare one but the lines are in
exactly the same place. It is difficult convincing myself that the toner
lies in fine lines on the OCD as there is no obvious repeat, coincident
with
the lines on the paper. There are hundreds of such fine lines with
nothing
making the most persistently tranferrd ones stand out.
If the following makes no difference I will try the earlier OCD that
worked
fine but the original owner managed to scratch numerous deep lines axial
to
the drum so produced heavy black lines obscuring the image. If the lines
stay in the same position then it will be a total mystery as I've
cleaned
,twice now, all surfaces near the OCD path. I should have said these
present lines are so fine they are just intrusive rather than blocking
information.

Going back to my original thinking, as this all started about coincident
with forced change of toner supplier. I made up a test batch of some of
the
toner mixed about 2 :3 of charcoal sieved down to 75 microns, the
thinking
is it would dilurte an excess of oil/styrene. It takes a while for this
to
work through the feed system but so far the ratio of blackness of wanted
image to tram lines has improved, I think. I can get hold of styrene and
have plenty of silicone oil but how do you mix 98 percent sieved
charcoal
with 2 percent or so of liquids without clumping? At this rate I may as
well
try formulating my own toner . My set of old brass lab sieves go down to
75
micron, any ideas for a source of mesh of order 30 or 40 micron?
Jesus. You're sure trying to do this the hard way!

Have you cleaned the laser module window, & tried swapping out the
cartridge?

--
W
. | ,. w , "Some people are alive only because
\|/ \|/ it is illegal to kill them." Perna condita delenda est
---^----^---------------------------------------------------------------



This is conventional copier with document glass and toner hopper feed. The
same problem must apply to cartridge/laser systems for when the original
specified cartridges are no longer available and supposed replacement
equivalents are not equivalent. Its just that the process (whatever it is)
is otherwise going on , unseen , inside the cartridge.
Click to expand...
Sorry, I had some sort of brainfart & was thinking that you were talking
about a laser, not a copier. You should clean all the mirrors in the
optical path, & look for stray hairs or other debris. Your problem is
incredibly unlikely to be related to the composition of your toner.

--
W
. | ,. w , "Some people are alive only because
\|/ \|/ it is illegal to kill them." Perna condita delenda est
---^----^---------------------------------------------------------------
 
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