Jeff: I don't see anything recent by you on comp.periphs.printers, so
I'll ask here on sci.electronics.repair:

I have a LaserJet 2200DN that is having trouble with duplex printing:

I followed your procedure that I found online and removed the sticky
goop from the solenoid you highlighted as the main problem, and used a
piece of that thin adhesive-backed felt, but I checked the other two
solenoids and determined that they were not sticking.

The first double-sided document I printed -- a single sheet -- printed
fine, but trying to print multiple copies produced a paper jam, with a
sheet sticking out partway -- on the point of feeding back in to print
the second side -- and a sheet in the duplexer tray.

Subsequent attempts to print even just one double-sided legal sheet
result in a jam: the paper seems to be on the point of feeding back in
to print the second side, but there is a "chattering" sound, and the
paper can be pulled out easily. If I try with a letter-size sheet, no
paper sticks out: the edge is just visible when I open the back -- same
when I do the Engine Test.

Sometimes there is a "ch-ch-ch-ch" sound just after I turn the printer
on -- a sound that I do not recall previously.

Before I "attacked" the solenoid, the machine would jam with the paper
sticking out further from the normal output slot, and with the leading
edge of a page about even with the black roller.

Could some parts of the mechanism have become "unsynchronized" while the
plate with all the gear wheels was removed and when activating the
solenoids enabled springs to turn gear wheels and shafts? -- I did turn
them back to the point where the solenoids were preventing them from
turning by the spring action.

I'd be grateful for any assistance you could provide.

Perce

On Mon, 11 Sep 2017 16:17:07 -0400, "Percival P. Cassidy"
wrote:

Jeff: I don't see anything recent by you on comp.periphs.printers, so
I'll ask here on sci.electronics.repair:

That's because I don't read comp.periphs.printers.

I have a LaserJet 2200DN that is having trouble with duplex printing:

I followed your procedure that I found online

That would be:
http://www.LearnByDestroying.com/jeffl/hp2200/hp2200.html

and removed the sticky
goop from the solenoid you highlighted as the main problem, and used a
piece of that thin adhesive-backed felt, but I checked the other two
solenoids and determined that they were not sticking.

How did you determine that? The printer is at least 10 years old. By
now, I would expect the foam on all three solenoids to have
devulcanized into a sticky goo. Even the slightest release delay
caused by the sticky goo will cause problems. At this point in time,
it is better to just assume that all 3 solenoids need cleaning and new
felt.

You should have taken out all 3 solenoids, cleaned off all 3
solenoids, and applied the replacement felt to all 3 solenoids. Only
this solenoid:
http://www.learnbydestroying.com/jeffl/hp2200/HP2200-04.jpg
causes it to paper jam or feed more than one page, but if the other
stick, there can be other problems.

You should also have checked if any of the solenoid cores are
magnetized. They get that way after many years of operation.

Since all this was in my instructions, I suggest you re-read the web
pages and please follow them this time.

The first double-sided document I printed -- a single sheet -- printed
fine, but trying to print multiple copies produced a paper jam, with a
sheet sticking out partway -- on the point of feeding back in to print
the second side -- and a sheet in the duplexer tray.

That is the classic symptom of a paper jam caused by sticky solenoids.
However, it is also a fair description of what happens when the
separation pad (RB2-6474) is worn out or filthy. I suggest getting a
"paper jam kit" or "maintenance kit" and do a general cleaning. It's
cheap and easy. Something like this:
http://www.ebay.com/120894286540

Subsequent attempts to print even just one double-sided legal sheet
result in a jam: the paper seems to be on the point of feeding back in
to print the second side, but there is a "chattering" sound, and the
paper can be pulled out easily. If I try with a letter-size sheet, no
paper sticks out: the edge is just visible when I open the back -- same
when I do the Engine Test.

Sometimes there is a "ch-ch-ch-ch" sound just after I turn the printer
on -- a sound that I do not recall previously.

There should not be any ratcheting sound when you turn on or run the
printer. I can't tell from where exactly what's wrong, but you may
have reassembled the printer incorrectly after cleaning the solenoids.
It could also be one of the other solenoids sticking. Use a
stethoscope to locate the source of the noise.

Also, my favorite screwup is re-installing the solenoids at an angle,
and then locking them down with the retaining screw. It looks right,
but it won't work. Loosen (not remove) the solenoids and rotate until
the hole in the frame aligns with the locating pin.

Before I "attacked" the solenoid, the machine would jam with the paper
sticking out further from the normal output slot, and with the leading
edge of a page about even with the black roller.

The distance between the first and 2nd page is a function of how
sticky the solenoid might be. The longer the distance, the more
sticky.

Could some parts of the mechanism have become "unsynchronized" while the
plate with all the gear wheels was removed and when activating the
solenoids enabled springs to turn gear wheels and shafts? -- I did turn
them back to the point where the solenoids were preventing them from
turning by the spring action.

No. The various rotating shafts are self aligning. As long as you
didn't take apart one of the clutches on the rotating shafts, it
should align itself.

I'd be grateful for any assistance you could provide.
Perce

Good luck.
--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On 09/11/2017 06:00 PM, Jeff Liebermann wrote:
On Mon, 11 Sep 2017 16:17:07 -0400, "Percival P. Cassidy"
wrote:

Jeff: I don't see anything recent by you on comp.periphs.printers, so
I'll ask here on sci.electronics.repair:

That's because I don't read comp.periphs.printers.

I have a LaserJet 2200DN that is having trouble with duplex printing:

I followed your procedure that I found online

That would be:
http://www.LearnByDestroying.com/jeffl/hp2200/hp2200.html

and removed the sticky
goop from the solenoid you highlighted as the main problem, and used a
piece of that thin adhesive-backed felt, but I checked the other two
solenoids and determined that they were not sticking.

How did you determine that? The printer is at least 10 years old. By
now, I would expect the foam on all three solenoids to have
devulcanized into a sticky goo. Even the slightest release delay
caused by the sticky goo will cause problems. At this point in time,
it is better to just assume that all 3 solenoids need cleaning and new
felt.

I moved the armatures until they touched the foam pads, and there was
not the slightest sign of sticking.

You should have taken out all 3 solenoids, cleaned off all 3
solenoids, and applied the replacement felt to all 3 solenoids. Only
this solenoid:
http://www.learnbydestroying.com/jeffl/hp2200/HP2200-04.jpg
causes it to paper jam or feed more than one page, but if the other
stick, there can be other problems.

You should also have checked if any of the solenoid cores are
magnetized. They get that way after many years of operation.

No sign of permanent magnetism in any of the solenoids.

Since all this was in my instructions, I suggest you re-read the web
pages and please follow them this time.

The first double-sided document I printed -- a single sheet -- printed
fine, but trying to print multiple copies produced a paper jam, with a
sheet sticking out partway -- on the point of feeding back in to print
the second side -- and a sheet in the duplexer tray.

That is the classic symptom of a paper jam caused by sticky solenoids.
However, it is also a fair description of what happens when the
separation pad (RB2-6474) is worn out or filthy. I suggest getting a
"paper jam kit" or "maintenance kit" and do a general cleaning. It's
cheap and easy. Something like this:
http://www.ebay.com/120894286540

Those parts were replaced a few months ago. That solved the problem that
it kept trying to pick up several sheets at once.

Subsequent attempts to print even just one double-sided legal sheet
result in a jam: the paper seems to be on the point of feeding back in
to print the second side, but there is a "chattering" sound, and the
paper can be pulled out easily. If I try with a letter-size sheet, no
paper sticks out: the edge is just visible when I open the back -- same
when I do the Engine Test.

Sometimes there is a "ch-ch-ch-ch" sound just after I turn the printer
on -- a sound that I do not recall previously.

There should not be any ratcheting sound when you turn on or run the
printer. I can't tell from where exactly what's wrong, but you may
have reassembled the printer incorrectly after cleaning the solenoids.
It could also be one of the other solenoids sticking. Use a
stethoscope to locate the source of the noise.

I wouldn't really call it a ratcheting sound. It's much softer and
"gentler" than that. More like parts rubbing together.

Also, my favorite screwup is re-installing the solenoids at an angle,
and then locking them down with the retaining screw. It looks right,
but it won't work. Loosen (not remove) the solenoids and rotate until
the hole in the frame aligns with the locating pin.

The only solenoid I removed was the first one, the one that did have the
sticky goo problem. I was very careful to position it correctly when I
reinstalled it.

Before I "attacked" the solenoid, the machine would jam with the paper
sticking out further from the normal output slot, and with the leading
edge of a page about even with the black roller.

The distance between the first and 2nd page is a function of how
sticky the solenoid might be. The longer the distance, the more
sticky.

Could some parts of the mechanism have become "unsynchronized" while the
plate with all the gear wheels was removed and when activating the
solenoids enabled springs to turn gear wheels and shafts? -- I did turn
them back to the point where the solenoids were preventing them from
turning by the spring action.

No. The various rotating shafts are self aligning. As long as you
didn't take apart one of the clutches on the rotating shafts, it
should align itself.

I'd be grateful for any assistance you could provide.
Perce

Good luck.

On Mon, 11 Sep 2017 20:19:31 -0400, "Percival P. Cassidy"
wrote:

I moved the armatures until they touched the foam pads, and there was
not the slightest sign of sticking.

http://www.learnbydestroying.com/jeffl/hp4200/Sticky-Relay.jpg
http://www.learnbydestroying.com/jeffl/hp4200/New-Felt-Pad.jpg
You have to smash the armature hard against the solenoid, simulating
what the energized core would do, in order to check for sticky
problems. I've found that even the slightest residue on the either
the armature or core will cause problems.

No sign of permanent magnetism in any of the solenoids.

This is for a different model HP printer, but with the same sticky
solenoid problems:
http://www.learnbydestroying.com/jeffl/hp4200/hp4200.html
It still paper jammed on double sided printing even after replacing
the pads. Here's a video of the residual magnetism problem with the
same solenoids:
http://www.learnbydestroying.com/jeffl/crud/hp2200-solenoid.wmv
(600K)
and a rather marginal test with a compass needle:
http://www.learnbydestroying.com/jeffl/crud/hp2200-compass.wmv
If you decide to use a tape head demagnetizer on the solenoid, be sure
to unplug the solenoid from the circuitry or you may fry something on
the motor controller board.

http://www.ebay.com/120894286540

Those parts were replaced a few months ago. That solved the problem that
it kept trying to pick up several sheets at once.

Ok, so much for that theory. Am I correct that it ONLY jams when
trying to print double sided? Did you have the paper jam problem
immediately after you replaced those parts, or did it take "several
months" for the problem to appear? I'm thinking that something might
have gummed up the feed roller or coated them with something stick,
such as printing sheets of mailing labels with some of the labels
removed. That will transfer rubber glue to the rollers.

I wouldn't really call it a ratcheting sound. It's much softer and
"gentler" than that. More like parts rubbing together.

I'll stand by my guess(tm) that it was reassembled incorrectly.

The only solenoid I removed was the first one, the one that did have the
sticky goo problem. I was very careful to position it correctly when I
reinstalled it.

So much for easy and obvious solutions. I don't know what might be
misassembled so the only way to find out is to take it apart again and
look for problems. It's a bit tricky to get it to print while
disassembled, but not impossible.

Good luck 2.0.
--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On 09/11/2017 08:42 PM, Jeff Liebermann wrote:

I moved the armatures until they touched the foam pads, and there was
not the slightest sign of sticking.

http://www.learnbydestroying.com/jeffl/hp4200/Sticky-Relay.jpg
http://www.learnbydestroying.com/jeffl/hp4200/New-Felt-Pad.jpg
You have to smash the armature hard against the solenoid, simulating
what the energized core would do, in order to check for sticky
problems. I've found that even the slightest residue on the either
the armature or core will cause problems.

No sign of permanent magnetism in any of the solenoids.

This is for a different model HP printer, but with the same sticky
solenoid problems:
http://www.learnbydestroying.com/jeffl/hp4200/hp4200.html
It still paper jammed on double sided printing even after replacing
the pads. Here's a video of the residual magnetism problem with the
same solenoids:
http://www.learnbydestroying.com/jeffl/crud/hp2200-solenoid.wmv
(600K)
and a rather marginal test with a compass needle:
http://www.learnbydestroying.com/jeffl/crud/hp2200-compass.wmv
If you decide to use a tape head demagnetizer on the solenoid, be sure
to unplug the solenoid from the circuitry or you may fry something on
the motor controller board.

http://www.ebay.com/120894286540

Those parts were replaced a few months ago. That solved the problem that
it kept trying to pick up several sheets at once.

Ok, so much for that theory. Am I correct that it ONLY jams when
trying to print double sided? Did you have the paper jam problem
immediately after you replaced those parts, or did it take "several
months" for the problem to appear? I'm thinking that something might
have gummed up the feed roller or coated them with something stick,
such as printing sheets of mailing labels with some of the labels
removed. That will transfer rubber glue to the rollers.

I wouldn't really call it a ratcheting sound. It's much softer and
"gentler" than that. More like parts rubbing together.

I'll stand by my guess(tm) that it was reassembled incorrectly.

The only solenoid I removed was the first one, the one that did have the
sticky goo problem. I was very careful to position it correctly when I
reinstalled it.

So much for easy and obvious solutions. I don't know what might be
misassembled so the only way to find out is to take it apart again and
look for problems. It's a bit tricky to get it to print while
disassembled, but not impossible.

Good luck 2.0.

Even though I could detect no sign of stickiness on the other two
solenoids, and no residual magnetism on any of them, I gave all of them
the recommended treatment, and now the printer is printed double-sided
without problems.

Thank you.

Perce

On Sat, 16 Sep 2017 12:17:57 -0400, "Percival P. Cassidy"
wrote:

Even though I could detect no sign of stickiness on the other two
solenoids, and no residual magnetism on any of them, I gave all of them
the recommended treatment, and now the printer is printed double-sided
without problems.

Nicely done. I assume the noise is also gone. I'm rather surprised
you didn't find any magnetized solenoids, because every one had the
problem to some degree. However, if you fix the pads so that there's
no metal-on-metal when the solenoid closes, the effect of the residual
magnetism is negligible.

Thank you.

Y'er welcome.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558