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Gebekophli

macrumors member
Mar 26, 2012
34
0
Berlin-Germany
Structure in red circle

Oggy: Why question mark for foam?

Because I have never opened any 27" display having a glance at that structure.

If you will please be so kind to compare it with the other section of the 24" display, which doesn't go through the connectors slot, but through the barrier:

There I think they drawed the same structure right under the edge of the LCD-panel, but in fact, there was nothing I could find. It was plain glass of LCD and plain plastic of the frame.

If the two plastic parts of the frames are not put together completely, there will be a gap open (two opposite arrows). But that way also would be different from connectors way.

The sun-streaks: I bought the iMac from a "gamer" and smoker. The clouds were really progressed. I knew before, but after the buy I needed one more month to find your "standard operating procedure".

Do you have an idea where to find the newest construction drawings of the actual display 2011 or 2012?

The story of the fax with the message, that there are displays of certain series and certain years involved in the problem is interesting.
 

cderees

macrumors newbie
Oct 13, 2006
1
0
Cleaned myself saved myself 400.00 GBP :)

Worked for me :). Only tricky part is removing the LED from it's frame. The rest is easy as long as you careful. Thank you Oggy !

Be careful when while opening the frame. Try not to turn the display around too much. Even better try to open the frame while it's in one vertical position. I had one accident with one iMac (dead pixels) - but they came back eventually.

Be carefull when you lift the LED.

https://forums.macrumors.com/attachment.php?attachmentid=287667&d=1306956612

There'S the dust!

https://forums.macrumors.com/attachment.php?attachmentid=287668&d=1306956612

Clean it very carefuly!

https://forums.macrumors.com/attachment.php?attachmentid=287669&d=1306956612


And at the end put everything back. Be gentle! LED can easily breake!

https://forums.macrumors.com/attachment.php?attachmentid=287670&d=1306956612

https://forums.macrumors.com/attachment.php?attachmentid=287671&d=1306956612


Good luck!



Oggy
 

GreenApple29

macrumors regular
Jun 8, 2008
204
4
Good day to all

Thanks To Oggy and Gebekophli i have successfully opend my 24 inch alluminium mac that suffers from the known issue of smudges on the lcd panel
to be honest i have studied that for a couple of weeks watching the comments of these two peop,e that have done this with success..
wa scare since i didnt have anotehr computer in cae there was something worng
so i did it!
put everything back on and boom...thank god it worked..
the problem is because we didnt have good lighting in the room we couldnt see well were exactly to clean
i hav to say that we cleaned the black part inside the lcd panel and the white part with a cloth (material that you clean sunglases)
we didnt put any spray r anyting else cos we were afraid in case we damage it
When i turned it on...the smudges were still there but this time a bit spread which means we had to clean it more and if we have done that teh machine woul have been in perfect conditon!
So my question is
what can we use to clean it with more success next time?now tat we have the know how?:)
here are a few pics and il post a vid too:)

photo1wzc.jpg



photo2ihl.jpg





photo3far.jpg
 
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Gebekophli

macrumors member
Mar 26, 2012
34
0
Berlin-Germany
Cleaning like I did

Green Apple29:
"So my question is
what can we use to clean it with more success next time?"

Like you I cleaned the iMac 9.1 early 2009 Display only once and my experience is not the result of research, but of trial:
I had completely success (no residuals of dust and stains, as far from smoking, I presume) with a window cleaning spray cleaner and house-holding kitchen-paper from that rolls.

Please work with a partner, one should concentrate his attention on holding the LCD-Panel with both hands, but not at the very corners. Place the LCD panel in a 45-dregree angle right upon the upper frames "edge" in order the avoid stress or movements of the multi-connectors at the upper edge of the LCD

and the other should do the cleaning job with no pressure force or jerky movements like window cleaning, but slower with all care in the edges.

The result is like window cleaning always is: You should control the result in strong working lights reflexes and correct the remaining dirt or traces.
Good luck!
 

GreenApple29

macrumors regular
Jun 8, 2008
204
4
Green Apple29:
"So my question is
what can we use to clean it with more success next time?"

Like you I cleaned the iMac 9.1 early 2009 Display only once and my experience is not the result of research, but of trial:
I had completely success (no residuals of dust and stains, as far from smoking, I presume) with a window cleaning spray cleaner and house-holding kitchen-paper from that rolls.

Please work with a partner, one should concentrate his attention on holding the LCD-Panel with both hands, but not at the very corners. Place the LCD panel in a 45-dregree angle right upon the upper frames "edge" in order the avoid stress or movements of the multi-connectors at the upper edge of the LCD

and the other should do the cleaning job with no pressure force or jerky movements like window cleaning, but slower with all care in the edges.

The result is like window cleaning always is: You should control the result in strong working lights reflexes and correct the remaining dirt or traces.
Good luck!
thank you for the reply Gebekophli
to be honest i was afraid to use a window cleaning liquid just in case there was an issue with the LED in the long term
on our first attempt we used an antistatic cloth *the one anyone uses to clean his sunglasses)
i think next time we will use window cleaning but not in a large quantity!!
after how long did this occur again?i mean the issue with the shadows?
i have seen some diagram that you made with the flow of the heat and how this issue can occur again
is there any way to prevent this?
thanx once again!!!
 

All Taken

macrumors 6502a
Dec 28, 2009
780
1
UK
Seriously just use optical lens cleaner from your local photography shop or optician, it is far better. Using window cleaner on a LED screen thats bare? are you mad?
 

Gebekophli

macrumors member
Mar 26, 2012
34
0
Berlin-Germany
The contribution to any topic should bei limited by a minimum of politeness and last but not least of knowledge of the herein discussed.
Who regulates the regular?

The answer is: Here you never will touch the sensible LCDs itself. The LCDs are sealed between two layers of glass, not of plastic. Thats why you need to bei careful with pressure, but not with detergent fluids.
The Spray fluid should not flow down to the multi connectors.
 
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rccoleman

macrumors newbie
Apr 15, 2012
3
0
I'm going to interrupt the argument to say that I successfully cleaned my 27" iMac screen and got rid of a heck of a lot of dust, and I really appreciate the pictures and advice from Oggy. It took quite a while as I figured out what needed to be unscrewed and pried, but I think I finally have it figured out :). My dust was caused by an ultrasonic humidifier (really fine white dust, a little like dust from sanding drywall joints), and I really have myself to blame for it. It'll get in pretty much anywhere.

I can add a couple of pieces of advice:

* Be very, very careful of the main screen connector in the middle of the board. It's easy to slide the connector onto the motherboard, but it seems like the socket is just held there by the wires that attach it to the motherboard. It moves very easily if you use any force at all to slide the cable into place, and I'm pretty sure you'd be in trouble if you flex it enough to break the solder joints or the wires. I wish that it was mechanically attached to the motherboard to take away some of the strain from inserting the cable.

* Wear thin latex gloves while working with the screen. It keeps fingerprints off of the glass and gives you some traction as you hold the pieces.

Thanks, Oggy!

Rob
 
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pzellner

macrumors newbie
Apr 18, 2012
1
0
Retape!

Ok, guys.
My 27' underwent a dusty screen substitution just some 6month ago, care of the mothership.
The "new" screen got his dust some month ago.
So not trusting Apple or LG for that matter anymore and being an aggressive DIYever I started looking around and found that in fact the cleaning was possible.
Thanks OGGY for that.
As all surgery in the innards of a computer or electronics you take risks and I was ready to risk the live of my iMac.
To get to the bare LG screen is no big issue (except for detaching the cables connecting it from the innards: The assemblers must have small hands). iFixit shows you how to get there and getting rid of the brackets fixing the screen to the case was just a matter of patience since they are partially glued.
Now, the screen assembly is crap. Congrats to LG and Apple's quality control.
A lot of possibilities for dust to get between what looks like the LED backlight plate and the LCD itself.
I decided to get rid of all alu and other taping and redo it.
I found a suitable 5cm high 3m alu tape at Conrad.de for 17 euros (50m length)
Better have a buddy while managing the cleaning and disassembly as well as the rest of the operations since often you need a third or fourth hand to keep the screen vertical or holding the LCD part while you clean it.
The dust is relatively easy to get rid of both from the backplate and the LCD. Check carefully that the surfaces are really clean before putting the LCD back in place.
/Innovation:
I retaped the whole covering the first 3mm of the LCD all around, paying attention to the edges and resealing all the backside where cable connections are and 3rd class plastic tape used OEM.
End of innovation/

Reassembly was easy (except for refitting the cables, since my hands are not the ones of a baby).

Special thanks go to Luigi who motivated me to intervene and who lend his hand(s) to get this done.
Without him it would have been a no-go.

Time: 3hous 30min (including the final testing and congrats beer!)

Tools: some torx drivers, fingernails, a damp no fuss cloth and the alu tape.

The screen now is working and dustless. Hopefully also dustsealed!

PS: I follow a relatively large number of Mac buddies. !00% of those with a recent iMac have the dust prob.

You may find relevant pix here:
http://pztake.blogspot.it/2012/04/monitor-imac-e-la-polvere.html
 
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lopat84

macrumors newbie
Apr 19, 2012
2
0
Hi

Hello everyone
I have some problems with my imac 27 late 2009 as it started form graphic card now I ordered a new one, while I was waiting for it I decide to clean my screen step by step with your tutorial;)
My problem is that once I reconnect the screen it dosnt display anything at all;/ black screen slightly lited;/
Any advise?? any help??
I`m stuck a bit, and i didnt change my graphic card yet.
Problem with it I had that It was showing blue vertical lines on lcd and on external monitor, so thats how I knew its not lcd problem.
Thanks for any help
 

Oggy

macrumors member
Original poster
Dec 31, 2010
58
1
hi! Sorry to hear that. :(

Are you sure you connected all the cables from the display to the logic board? It sounds to me like you missed some connector when assembling.
 

lopat84

macrumors newbie
Apr 19, 2012
2
0
Hi.
Yes I`m sure about that, v-sync cable looks a bit broken, could it make that sort of black display??
 

Gebekophli

macrumors member
Mar 26, 2012
34
0
Berlin-Germany
Video-30pin-Connector broken?

Yes, any break of the video cable may result in black screen.
Is it possible, you show photographs from both sides? Cable end and socket?

The video cables socket is normally the first "victim" of inappropriate influence of forces.
I needed quite a few minutes to learn to understand the mechanism of the video-cables coupling clamp and tried to lift the video cable like the former video cables in iMacs early 2009 or earlier.

Video cables defects are the most common disassembly fault I think.
Only glossy glass breaking was more common.

And I want to tell my compassion too.

This is your new cable, if it's only the cable:

(wrong cable deleted)

this should be the right one for 2009 27" iMacs:

http://applecomponents.com/items/92...playport/0000004393?pn=1&cmp=0159&per_page=30
 
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Gebekophli

macrumors member
Mar 26, 2012
34
0
Berlin-Germany

Thanks for the photographs.
Everybody telling about his cleaning experiences should show photographs.
I made something similar with the display housing of an 24" iMac early 2009.
I did'nt payed that much attention on an "all-sided closing" of the metal frame, but I sealed too the sides of the metal-frame before I remounted the so called "User Mountings" (the User is Apple from the point of view of LG)

More important is the backside, there the cable entries under the tin cover and its wholes and edges of the proprietary electronics of the display.
Correction: This hint might be misunderstand able: No tapes under the tin cover! Never fix or lock the multi-connectors itself, they would tear off electronics if moving is prevented, which is vital with temperatures changings.

The second picture is the real worthwhile to me.
I can detect the same dust marks and jet blow-out marks in the dust pattern as I know from my iMac, but not in an excessive degree of progress.
Look at them in my pictures above.
The gray stripe of isolating material (we named it "foam") is not able to prevent from leaks in air-stopping efforts by LG.

You may stop this process only by closing the tin cover of the electronics.
Greetings to Italy!
 
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GreenApple29

macrumors regular
Jun 8, 2008
204
4
hello to all once again
we opened the imac 24 inch one more time and will be uploading a video quite soon
the problem unfortunately seems to remain!
we tried with an optic lens cleaning liquid but the shadows are still there
we are thinkling next time..if there is going to be any to use a gass cleaning liquid..
have to say that inside the lcd both in the white part and on the back of the glass there arent any visible shadows or dust...so seems like a dead end or at least we didnt want to put more pressure during the cleaning or a heavy duty cleaning detergent
I think next time will use something stronger plus will try and follow Gebekophli's suggestions regarding the possible solution for the blockage of the dust once and for all



oh seems like macrumors post editor doesnt have a youtube embed button so when the video editing finishes ill just upload the link here for anyone that would like to see the process
Once again would like to thank Oggy and Gebekophli of course!
 

Gebekophli

macrumors member
Mar 26, 2012
34
0
Berlin-Germany
Green Apple29:

The pictures above made from you, especially the pic of the backside of the display housing shows to me, that there is existing a far different problem exceeding the "normal dust problem", I was able to clean with methods of windows cleaning.

Your displays backside look more like this situation of the 20" iMac late 2006, I showed on my first pictures with the heat marks opposite the power supply and the nicotine stains, which resists cleaning:

I can see the consequences of heat and a very dark kind of smudges, dirt, whatever it is. Let's say so: If you are not able to clean the TFT-Backside and the "white" light diffusor, the display is more or less useless, not to use properly.

As you should know, I'm a friend and guest of greece since 40 years now, I spent more than 5 years there in pieces of 6 weeks each, and I know the situation there, problems of dust air pollution, of smoking, and last but not least of the heat in summer. All together make a different dust and dirt, with a larger amount of "burning in" problem.
But it is hard to understand, that you don't see any dirt whilst the cleaning procedure, but afterwards when the display is in function again.
It sounds, as if there is only the "burned-in component" remaining.

When I give you now the advice, to disassemble the highly breakable "white" light diffusors (only the first layer) and clean them without any mechanical touching with a solution of "chlorine", in greece clorini, χλώριο, then you know what I mean. I want to bleach the stains. It's what we call an "ultima ratio", "έσχατη λύση" for a thing, which is lost otherwise.

As far as I know about chlorine, it will not attack the plastics from polystyrene (polystyrol) in 2006 iMacs and of PMMA, polymethylenemethacrylate (in 2009 iMacs). Try it at the very rim first, because the white light diffusors are carrying a silverish coat. Rinse the layer with much, much water afterwards.

Because the TFT-Layer is coated with an unknown coating, which has some light polarizing properties, I will not recommend to do so with chlorine on the backside of the TFT-panel. There I would try a window-cleaning spray, with careful cleaning procedure without any pressure upon the glass. And the assistance of a partner, so that there is always somebody having a helping hand.

Anybody may argue against this idea.
One please I have: Couls you be so kind to offer your photos as a URL-link to a picture and video hosting like Image-shack?
http://imageshack.us/
Opening this page costs me the half of my daily 16 Mb on the smartphone.
 

GreenApple29

macrumors regular
Jun 8, 2008
204
4
Green Apple29:

The pictures above made from you, especially the pic of the backside of the display housing shows to me, that there is existing a far different problem exceeding the "normal dust problem", I was able to clean with methods of windows cleaning.

Your displays backside look more like this situation of the 20" iMac late 2006, I showed on my first pictures with the heat marks opposite the power supply and the nicotine stains, which resists cleaning:

I can see the consequences of heat and a very dark kind of smudges, dirt, whatever it is. Let's say so: If you are not able to clean the TFT-Backside and the "white" light diffusor, the display is more or less useless, not to use properly.

As you should know, I'm a friend and guest of greece since 40 years now, I spent more than 5 years there in pieces of 6 weeks each, and I know the situation there, problems of dust air pollution, of smoking, and last but not least of the heat in summer. All together make a different dust and dirt, with a larger amount of "burning in" problem.
But it is hard to understand, that you don't see any dirt whilst the cleaning procedure, but afterwards when the display is in function again.
It sounds, as if there is only the "burned-in component" remaining.

When I give you now the advice, to disassemble the highly breakable "white" light diffusors (only the first layer) and clean them without any mechanical touching with a solution of "chlorine", in greece clorini, χλώριο, then you know what I mean. I want to bleach the stains. It's what we call an "ultima ratio", "έσχατη λύση" for a thing, which is lost otherwise.

As far as I know about chlorine, it will not attack the plastics from polystyrene (polystyrol) in 2006 iMacs and of PMMA, polymethylenemethacrylate (in 2009 iMacs). Try it at the very rim first, because the white light diffusors are carrying a silverish coat. Rinse the layer with much, much water afterwards.

Because the TFT-Layer is coated with an unknown coating, which has some light polarizing properties, I will not recommend to do so with chlorine on the backside of the TFT-panel. There I would try a window-cleaning spray, with careful cleaning procedure without any pressure upon the glass. And the assistance of a partner, so that there is always somebody having a helping hand.

Anybody may argue against this idea.
One please I have: Couls you be so kind to offer your photos as a URL-link to a picture and video hosting like Image-shack?
http://imageshack.us/
Opening this page costs me the half of my daily 16 Mb on the smartphone.

hello there
first of all i would like to apologize for the size of the images whic i will take care off soon afer this message
as already mentionedi have opned the imac twice and cleaned it as much as we could..actually a friend did the whole process and im not siure if there is going to be a third time
i bought a new mac mini 2.7 i7 and wanted to sell my imac so i can get a scree for that....
it seems that i stuck with the imac and problably wil use it as a monitor through screen sharing (since the imac dopenst have any ports to connect teh mac mini directly)
im quite dispointed, if the screen of teh imac isnt clean obvioyusly i cant sell it to anyone...the shadows arent that bad...but they are visible
Glad tyo hear that you like spedning your time here in greece
I hope its not only in athens but somehwere with the sea next to you!!heheh
Thanx for all the detail info abot the cholrine method (great use of teh greek words by teh way!!)
if there is going to be a third and final tme i will definately try this:)
 

skuid87

macrumors regular
Apr 2, 2012
101
1
Hi all,

Thanks to the OP for raising this thread. Alot of useful info here.

I have a late 2009 27" iMac. I purchased AppleCare so this is still under Warranty.

I have noticed the brown/dark smudges at the top-right of my screen.

I recently took out the optical drive to replace it with an SSD. I can put it back in before sending to Apple (I'm sure they won't be happy about me opening the Mac).

But before I go through all that trouble, can you guys confirm from your experience that Apple WILL replace the screen? I don't wanna go through all this hassle only to be told that they won't do anything about it.

Please advise...
 

pilotito

macrumors newbie
Apr 28, 2012
1
0
Did it with 21.5" iMac and it worked

Thank you for all your tips here.

Hardest things:
  • Figure out what tape to remove. Its ALL the tape at the borders
  • Screw the drivers back with the magnets SO CLOSE. A nightmare

Thanks again!
 

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GreenApple29

macrumors regular
Jun 8, 2008
204
4
Hello to all again
after two attempts we made a video for anyone interested
it isnt the best but its a basic how to for anyone that want to try
(there are some annotations that need to be added as well)
hope it helps
again many thanks to Oggy, Gebekophli and my friend Gregory that dedicated so many hours to this project

the video can be found on youtube here

http://www.youtube.com/watch?v=P70WzU0ABBs
 

skuid87

macrumors regular
Apr 2, 2012
101
1
Hello to all again
after two attempts we made a video for anyone interested
it isnt the best but its a basic how to for anyone that want to try
(there are some annotations that need to be added as well)
hope it helps
again many thanks to Oggy, Gebekophli and my friend Gregory that dedicated so many hours to this project

the video can be found on youtube here

http://www.youtube.com/watch?v=P70WzU0ABBs

Wow. Thanks for this. Great effort... I'm sure it'll be very useful for many people. This is the stuff that makes the MacRumours forum community so great.
 

GreenApple29

macrumors regular
Jun 8, 2008
204
4
Wow. Thanks for this. Great effort... I'm sure it'll be very useful for many people. This is the stuff that makes the MacRumours forum community so great.

thanx:)
all the credit go of course to teh guys already mentioned herte for teh great details that without them this wouldnt have been possible
and especially to my friend gregory who spend HOURS of hard work!!

the video needs to have more annotations and will be updated soon!
 

Mr Rogers

macrumors regular
Oct 24, 2003
225
3
Hong Kong
Bloody Apple!!!!!

Here's a good one.

Just sold my top end BTO 2011 27in i7 for US$2000 - a good price in Hong Kong - as a stop gap until refresh I picked up the company's other same spec 2011 model purchased in July - and this was a machine that was sent as a replacement unit for a yellow tint issue that Apple maintains does not exist.

I now have the greying smoke marks on both upper corners of the machine, a machine that has seen about 80% less use than the one I've sold - I now have to waste considerable time getting the LCD replaced - given its still under warranty and has AppleCare I don't want to be swapping LCD panels each quarter - however, this is exactly what I'll do until Apple get the message that it is selling defective goods.

This issue has existed since the October 2009 refresh and was not remedied in May last year - wonder how long it will take Apple to get sick of me and offer a brand new replacement.

I guess I'm lucky, obviously I can do the repair detailed here, but the reality is Apple should be replacing all screens regardless of age and warranty status, particularly since its a known issue that has now existed for nearly three years.

So much for Apple quality, if they can get it right on one machine, they should be able to get it right on all machines - its a bloody disgrace and Apple are liable for this nonsense.
 
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