HP CM1312nfi epilogue and bewilderment

[[email protected]]

As expected the registration was off when it got the thing together. So what ?

Well it fixed itself.

Not so long ago I setup an HP regular printer and it needed alignment. It was pretty much automated and the process was simple. Print the test page and then scan it., After that it put in all the parameters. Pretty much straightforward and not hard to figure out how the process works.

However with this thing, I am sitting nearby it and talking on the phone. Ihear a motor start up and thew display reads "calibrating" or something tothat effect. So far so good.

It appeared to be done at one point so I tok and printed a picture, the same one I had printed before that showed the registration errors.

The problem was corrected.

How ?

Thing is, I did not scan any printed document, test or otherwise. Does thisthing have Xray vision or some shit ? How did it know the registration wasoff and how much and what direction ?

I am still much less unhappy to have the thing working, but shit l;ike thisbothers me. How in the hell can it set the registration without some feedback concerning the error ? Perhaps detectors right in the toner cartridges or something ?

The proof is here, it did it. This is not my imagination unless I am dreaming. If so this post will not appear on SER and we can go back to thinking we know everything.

 

[Genesys]

As expected the registration was off when it got the thing together. So what ?



Well it fixed itself.



Not so long ago I setup an HP regular printer and it needed alignment. Itwas pretty much automated and the process was simple. Print the test page and then scan it., After that it put in all the parameters. Pretty much straightforward and not hard to figure out how the process works.



However with this thing, I am sitting nearby it and talking on the phone.I hear a motor start up and thew display reads "calibrating" or something to that effect. So far so good.



It appeared to be done at one point so I tok and printed a picture, the same one I had printed before that showed the registration errors.



The problem was corrected.



How ?



Thing is, I did not scan any printed document, test or otherwise. Does this thing have Xray vision or some shit ? How did it know the registration was off and how much and what direction ?



I am still much less unhappy to have the thing working, but shit l;ike this bothers me. How in the hell can it set the registration without some feedback concerning the error ? Perhaps detectors right in the toner cartridges or something ?



The proof is here, it did it. This is not my imagination unless I am dreaming. If so this post will not appear on SER and we can go back to thinkingwe know everything.

I have an inkjet that does its alignment like this. Put new carts in it, and a few minutes later it says "Aligning" and aligns itself without printinga test page, let alone needing to scan it.

 

[[email protected]]

Yeah, and just how the **** does it do that ?

 

[Smarty]

Yeah, and just how the **** does it do that ?

Purely guessing here:

Might be some impossible to see registration marks on the inside of the
scanner cover which are seen at UV frequencies only.

Could be visible markings which are normally concealed because the
scanner cover is down / closed.

Inside scanner cover may have a deliberate "texture" designed to be used
as a calibration "graticule"

 

[[email protected]]

Possibly on some models, but I didn't scan anything. This remains a mystery.. Is it possible though that it reads right off the rollers ? Sensors on the transfer plate ? The service manual of course gives underwhelming detail on the thing......

I dunno. I really didn't read all 300+ pages of the service manual, I looked real hard for the registration process and didn't find it. And then the thing starts humming and it fixes itself. That IS how it happened. Afterwardit printed fine, registration was right on the money. I never scanned anything or even pushed a button.

For now, the most likely answer according to Occam's razor is VOODOO !

 

[[email protected]]

Less bewilderment.

The laser assembly I took out ? How long did you think it was going to sit there before I took it apart ? OK, now this is a bit unusual, but a friend of mine took it apart before I did. he was there and said "got a phillips ?". I should have known better but you know, I don't care.

Regardless, I finally took it apart myself. I looked at it intensely, thereis a motor with a four sided mirror. There are all these other mirrors andlenses. Once you see it you get the idea how it works. In fact if anyone is interestec maybe I'll take it apart again and get some pictures, but for now....

I am pretty sure I fixed it. I looked at that four sided rotary mirror and it did not look shiny. Quite dull in fact. Remember I said it was not in the best of environments ? We are talking four heavy smokers in a small house.. That small house also means that between laundry and cooking it was also quite humid.

The gunk on the mirror was not hard to get off with a Qtip.

There was never an issue with tomer at all, or high voltage or anything else, it was simply that the LASER beam could not get out of the box. Now if the replacemetn fails I have one.

 

[N_Cook]

Less bewilderment.

The laser assembly I took out ? How long did you think it was going to sit there before I took it apart ? OK, now this is a bit unusual, but a friend of mine took it apart before I did. he was there and said "got a phillips ?". I should have known better but you know, I don't care.

Regardless, I finally took it apart myself. I looked at it intensely, there is a motor with a four sided mirror. There are all these other mirrors and lenses. Once you see it you get the idea how it works. In fact if anyone is interestec maybe I'll take it apart again and get some pictures, but for now....

I am pretty sure I fixed it. I looked at that four sided rotary mirror and it did not look shiny. Quite dull in fact. Remember I said it was not in the best of environments ? We are talking four heavy smokers in a small house. That small house also means that between laundry and cooking it was also quite humid.

The gunk on the mirror was not hard to get off with a Qtip.

There was never an issue with tomer at all, or high voltage or anything else, it was simply that the LASER beam could not get out of the box. Now if the replacemetn fails I have one.

So what is the air flow path that allows gunk in there? the ones I've
looked into are sealed units with no ventilation requirement

 

[[email protected]]

Good question. It looks open to me but there could be pieces of glass there. There are no gaskets or anything like that.

That little motor does not need airflow like a Phase Linear 700, and the LASERs are not even in there, they are on a PC board off to the side. The unit could easily be sealed and still work.

I also wonder how this stuff got attrac ted to the one mirror in the moiddle.

It was a matte finish, metal color not dark. Not brownish at all. It wiped off with a Qtip.

What could it have been ?

 

[N_Cook]

Good question. It looks open to me but there could be pieces of glass there. There are no gaskets or anything like that.

That little motor does not need airflow like a Phase Linear 700, and the LASERs are not even in there, they are on a PC board off to the side. The unit could easily be sealed and still work.

I also wonder how this stuff got attrac ted to the one mirror in the moiddle.

It was a matte finish, metal color not dark. Not brownish at all. It wiped off with a Qtip.

What could it have been ?

Is the dirty Qtip attracted to a magnet?
Maybe a magnet inside and a hall-effect somewhere for synching and a
worn bearing somewhere

 

[[email protected]]

I can't really answer that, the Qtip is history. Even if I had it though, the surfaces I cleaned were so small that I may not have been able to tell if the particles were magnetic. We are talking about 2.5mm X about 15 mm or so. That is not alot of gunk with which to work.

What this means though is that I have pretty much every major component spare for this thing. The donor unit had a bad transfer plate, it was obviously FUBAR. Tell you this much, I think a cat pissed in it. A little corrosionhere and there y'know ? Far as I can figure now, other than the transfer plate being bad I got the HV board, which I did change and didn't bother to cvhange back. The fusert is an item to have as well. I already started cutting on the original black toner to see