iMac Intel 21.5" Retina 4K Display Adhesive Strips Replacement

Schritt 1

With the hinge free to move, the iMac will be unbalanced and hard to work on. Place an iMac service wedge in the stand to stabilize the iMac.
If you're using the iFixit cardboard service wedge, follow these assembly directions to put it together.
If you don't have an iMac service wedge, work very carefully—the display can easily fall out and break if the iMac moves unexpectedly.

Schritt 2

Before you install new adhesive strips, remove all of the old adhesive from the perimeter of the rear enclosure.
If you are re-using your existing display, you must also remove the old adhesive from the back of the display.
Peel off the old strips of adhesive using tweezers or your fingers. Start at the bottom and peel upward towards the top of the device.
After all the old adhesive is removed, carefully clean off the adhesive residue with high-concentration isopropyl alcohol (90% or greater) and a lint-free cloth. Wipe in one direction, not back and forth.
Don't skip this step, or your new adhesive strips may not bond properly, and the display may fall out of your iMac.

The aluminum frame have a plastic zone. Could the isopropyl alcohol damage the plastic surface?

Fer Triva - 17/01/21

Hello! Isopropyl alcohol should not damage the plastic surface.

Arthur Shi - 18/01/21

It’s not clear if you’re supposed to remove the black strips under the adhesives from the screen. Sometimes they come off when removing the main adhesives, but they seem to be two separate layers.

online -

Only the adhesive should be removed—the black strips underneath them should stay in place.

Arthur Shi -

“Only the adhesive should be removed—the black strips underneath them should stay in place.”

By fault I’ve removed the black strips, now there is a gap between the glass and the aluminum frame in the bottom.

the display is perfectly pasted, it’s only a matter of appearance…

If I open the computer again, what kind of adhesive tape (caption tape?) could I use to eliminate the gap between the glass and the frame?

Or it’s better to let it go…

Thanks for your support

Massimiliano Nannetti -

Hi Massimiliano ,

You should be fine. The bottom edge doesn’t have black strips. It should be bare metal. However, there shouldn’t be any gaps between the glass and the frame. Make sure that the adhesive is fully adhered on the bottom edge.

Arthur Shi -

Hi Arthur,

my English is not perfect…

I would mean that I removed all the black strips under the adhesives on the screen; so I believe that the glass has become too thin compared to the bottom aluminium frame.

I thought to open the Mac again and put some black strips to increase the thickness of the glass screen but I don’t know what kind of tape I should use (Kapton or other?).

And then I will put a new set of ifixit adhesives strips.

Maybe it’s a waste of time… it’ s only an aesthetic matter

Thanks again

Massimiliano Nannetti -

Thanks for the clarification. Since there is always a chance to crack the screen glass when cutting the adhesive, I’d suggest not to open up the iMac again. However, if you do open it, I suggest using Tesa tape.

Arthur Shi -

Thanks Arthur,

I will follow your suggestion… I will not open again my computer…

Now it works very well and fast.

Massimiliano Nannetti -

So, the bit about the adhesive strips really needs to be clarified. Nowhere in the instructions is there talk about multiple layers of adhesive, one that should be removed and one that should remain. And looking at the pictures further on, clearly the wider sections where the adhesive go are completely clean of any black strips. However, on the screen side, I’ve noted that indeed there are two layers, at least on the top. And removing both layers leads to the adhesive *not* really taking hold and the screens falling out. Really wish this had been clearer. I’ve helped dozens of people upgrade their iMac but after the first time that I had to replace a screen due to it falling and breaking, I’ve been using clear strong adhesive tape externally on the corners to ensure that the screen stays in place. Ugly, but better than the risk.

David -

I’m putting in an SSD, don’t have any strips. Would super glue work?

natfrey -

no! don't do that. if for any reason in the future you need to open it up again, you will only destroy your screen. you can get strips really cheap on Amazon.

David -

I too started removing the second layer of adhesive strips before reading these comments. PLEASE update the article to reflect that the other black strips should stay!

Mark Sandell -

Schritt 3

Your adhesive strips should have a microphone notch pre-cut in the strip labeled 4R.
If your 4R strip does not contain a notch, follow this guide instead.

As far as I can tell, this model still had the mic at the top near the webcam, not at the bottom, so this notch is not needed for this model (2014 21.5” iMac A1418)

Neddy - 07/12/20

Schritt 4

Lay out the adhesives strips beforehand so you won't accidentally install a strip in the wrong place:
Strip 01 on the top left
Strip 02 on the top right
Strip 03 on the right vertical
Strip 4R on the bottom right, dark side facing up
Strip 4L on the bottom left, dark side facing up
Strip 05 on the left vertical

Schritt 5

Start with strip 03, which goes on the right vertical side of the rear enclosure.
Before you peel off any backing, line the adhesive strip up along the frame of the iMac to get an idea of where it goes.
Grasp the blue tab and peel the short piece of backing off the back of the strip to expose a section of adhesive to attach to the enclosure.

Schritt 6

Insert the tip of a spudger into the hole at the end of the strip where you just removed one layer of backing. Insert the spudger from the side that still has a layer of white backing on it.

Schritt 7

With the spudger still poking through the hole in the adhesive strip, push the spudger tip into the corresponding hole in the frame of the iMac.
Using the hole and spudger to anchor the position of the adhesive strip, line the strip up against the right edge, gently pulling up against the spudger to ensure the strip is taut, and stick it onto the frame.

Schritt 8

Once you've aligned the bottom half of the adhesive strip, peel the longer piece of backing out from behind the strip.
If the bottom half isn't aligned properly, you can carefully peel it up and re-stick it before peeling off the lower backing strip. Be sure to use the spudger tip to anchor the top.

Schritt 9

Align the upper half of the strip with the right edge of the rear enclosure, and stick it down.

Schritt 10

Use your finger to smooth out the strip. Make sure it is neatly aligned with the right side of the frame and that it sits flat.
Do not peel off the front adhesive backing yet.

Schritt 11

Work your way counter-clockwise around the perimeter of the iMac, adding three more adhesive strips in the same manner:
Strip 02 on the top right
Strip 01 on the top left
Strip 05 on the left vertical

Schritt 12

The next few steps will show you how to install the bottom right adhesive strip (strip 4R), which includes a notch that must be aligned with the microphone.
Read through this step and the next four steps before you attempt the procedure.
Grasp the red pull tab on strip 4R and pull to separate about 2 inches (5 cm) of white backing from the strip.

These steps instruct you to install the lower strips to the iMac frame first, as that is what Apple instructs their techs to do. If you have an iMac without a microphone hole, you can choose to install the lower strips onto the display first. Peel the blue tab instead of the red to expose the adhesive. Carefully place the adhesive along the bottom edge of the display. The L-bend on the adhesive should match the display contours.

Arthur Shi - 08/10/20

i have no microphone hole - which is good . . . because the 4R and 4L stips must be labelled incorrectly as the L’s are on the wrong side. Also the strips don’t completely cover the bottom. And there are no holes in these strips making placement less secure. Someone certainly goofed. (Reckon I’ll use snipped off L’s to cover the open space.

George Guess - 01/03/21

Ah, the L strips don’t overlap - so they’re long enuf, but they are still reversed.

George Guess - 01/03/21

Schritt 13

Fold the loose white backing to a right angle and pinch the crease with your fingers.
This exposes 2 inches of adhesive while folding the red tab out of the way.

Schritt 14

The microphone hole is the center hole flanked by two larger holes.
Align the adhesive strip to the bottom edge by positioning the microphone notch over the microphone hole.
If your iMac does not have a microphone hole, align the right end of the strip such that the L-bend sits next to the right vertical adhesive. The L-bend should not overlap the right vertical adhesive.
The adhesive tears easily. Be careful not to pull on the strip with too much force.
Once you have aligned the strip, carefully set the left exposed edge onto the iMac to secure the alignment.

The strips that I received from OWC do not have a notch cut out for the microphone. The instructions advise you, for 2017 and later 21.5” iMacs, to cut about 2 inches off from the left side of the strip so you do not cover the microphone hole.

Peter Hillman - 18/10/20

As far as the remaining 2 inches I cut off, I snipped off a little more on the right side to leave a small gap for the microphone and placed that small remaining part in the center where it should have been if there was no microphone, just to complete the adhesive.

Peter Hillman - 18/10/20

I have done quite a few of these now. It is easier to apply the bottom strips to the Display, rather than the housing. With the Red tabs folded at 90 degrees to the adhesive. You can then remove these tabs with the display kind in place, secured by painters tape on the out side before closing it up.

Charlie Nancarrow -

Don't make the mistake i just did - if you want to cut a notch, cut the BOTTOM 2/3rds section of the strip, not the top! :P

Also, here's a some pics of the mic location in the 2017 retina version from iFIXit: Muffled Microphone - iMac 21.5" (mid 2017) - Following Adhesive Strips.

Philip Sedlmair -

Schritt 15

Peel away the white backing behind the strip to expose the remaining adhesive.

Schritt 16

Run your finger from left to right along the length of the adhesive strip to ensure it is straight and unwrinkled, pressing down as you go to adhere the strip to the iMac.

Schritt 17

Repeat the previous steps for the 4L adhesive strip, placing it along the bottom left edge of the iMac.
The 4L strip should be positioned such that the L-bend sits next to the left vertical adhesive. The L-bend should not overlap the left vertical adhesive.

Schritt 18

Gently set the display in place over the iMac and align it carefully.

In my experience, it is easier to lay the Mac flat on its back, especially if you do not have a wedge, because the display will tilt up and down and you do not want that happening. With the Mac on its back, I removed all the front adhesive strips and then angled the display (not a big angle) against the chin making sure it was even on both sides. Then reconnect the video cables and gently bring the display down into the proper position. Step 23 below seems too much of a hassle to try and get the bottom adhesive strips out while the display is resting on them, and taping the bottom of the display in Step 19 also seems to be a hassle.

Peter Hillman - 18/10/20

Schritt 19

Use painter's tape or masking tape to temporarily secure the bottom edge of the display to the iMac's enclosure.
The tape preserves the display's alignment, and allows you to safely swing the top edge of the display open to access the display cables.
Don't wrap the tape around the back of the iMac, or you may shatter the screen when you connect the cables.

Noooo!! I followed this step and promptly cracked my screen!!!! You need to be extremely careful NOT to wrap the tape around the back of the computer. These images make it look like it's wrapped around, but if you do that, you won't be able to lift the screen at all to attach the display cables. Why?!!!!!

Mark Sandell -

Oh no! I'm so sorry to hear this! Thank you for sharing your experience—I'm going to add a warning into the step.

Arthur Shi -

Schritt 20

At this point it's a good idea to test your repair, in order to make sure your iMac works properly before you seal it back up. Follow the next three steps to temporarily reconnect the display cables and boot up your iMac prior to pulling the protective film off the adhesive strips.
If you've already verified that your iMac is working correctly and are ready to seal it up, skip the next step.
Insert the display power cable into its socket on the logic board.

I am powering the unit back up to test all is working. Screen is black but fan is running loud. I’ve decoupled the power and confirmed both the display cables are connected. Note - I replaced both the HDD with a SSD as well as upgraded the RAM from 8GB to 16GB.

Neil Harfert -

Schritt 21

Use a pair of tweezers or your other hand to gently insert the display data cable connector into its socket on the logic board.
Be sure to press it straight into the socket, and insert it completely.
Secure the metal retaining bracket on the display data cable downwards towards the logic board.

While the previous step refers to “cables,” plural, this step suggests that only the display cable needs to be reinstalled in order to test working order. In my experience (iMac 21-1/2" Retina 4K Display, late 2015), I found that I had to also reconnect the camera/microphone cable in order for the screen to work. [6/7/21]

Gary Heurich - 07/06/21

Schritt 22

Set the display back on the iMac's rear enclosure.
At this time, plug in your iMac, power it on, and test your repair before moving on to actually sealing up the computer. Be sure to check for full functionality of any hardware you removed or disconnected.
When you are finished, shut the iMac down and unplug the power cord before you continue.

At this point I tested everything to make sure it worked, including the microphone. It was a bit muffled so I poked it with a pin to try and clear it. This was incredibly stupid because (a) the muffling was due to the backing which I was about to remove from the strip (b) poking with a pin broke the microphone.

I’m not going to buy a new microphone (£72 apparently) and a new set of strips, so I’ll get an external USB microphone instead.

But to anyone else, if the microphone sound is muffled, don’t worry!

rjbusenet -

Schritt 23

Verify that your iMac is turned off and unplugged from power before you continue.
After confirming that your iMac functions properly, disconnect the display cables and carefully lean the display forward.
Remove the film from the two bottom strips by reaching in from above with a pair of tweezers and pulling the blue tabs straight up from the bottom edge of the display.

Schritt 24

Reconnect the display power and data cables for the final time.
Remember to secure the metal retaining bracket on the display data cable.

Schritt 25

Check the glass directly in front of the webcam for dust and other contaminants. If necessary, wipe it down with a microfiber cloth before you seal up the display.
Steady the display with one hand as you remove the protective film in the following steps, or rest it lightly against the iMac's enclosure.

Schritt 26

Remove the protective film from strip 01 by pulling its tab straight up.

Schritt 27

Remove the other side of the protective film from strip 01.

Schritt 28

Repeat the previous steps to remove the protective films from all the remaining adhesive strips.

Schritt 29

To ensure a strong bond, carefully tip the iMac flat on its back (with the screen facing straight up) and press carefully but firmly around all four edges of the display.
Remove the tape securing the display to the rear enclosure.
Check the display after 24 hours to make sure that it isn't loose on the iMac.

iMac Intel 21.5" Retina 4K Display Adhesive Strips Replacement

Einleitung

Werkzeuge

Ersatzteile

Schritt 1

Schritt 2

Schritt 3

Schritt 4

Schritt 5

Schritt 6

Schritt 7

Schritt 8

Schritt 9

Schritt 10

Schritt 11

Schritt 12

Schritt 13

Schritt 14

Schritt 15

Schritt 16

Schritt 17

Schritt 18

Schritt 19

Schritt 20

Schritt 21

Schritt 22

Schritt 23

Schritt 24

Schritt 25

Schritt 26

Schritt 27

Schritt 28

Schritt 29

Tinte & Feder

Arthur Shi

Ein Kommentar