iMac (21.5-inch, Late 2012): Display Panel - Replacing Very High Bond (VHB) Strips
First Steps

    Display Panel Removal
    Display Panel - Removing Very High Bond (VHB) Strips

Tools

    ESD wrist strap and mat
    Service wedge, iMac
    Black stick
    Replacement VHB strips, kit 076-1422 (10-pack)

Steps for Removal

If VHB strips are not already removed, follow instructions in Display Panel - Removing Very High Bond (VHB) Strips.
Steps for Reassembly

1. Insert the iMac service wedge. The AC receptacle is covered when the service wedge is installed correctly.

Steps for Reassembly

2. Each VHB strip has an ID number (on the pull tab)  and part number (946-xxxx)  printed on the strip.  Use the picture below as a template to verify you have all the needed VHB strips. Lay out the VHB strips before installing them onto the computer and check them for damage. Make sure there are no wrinkles or exposed sections on the strip. Damage can cause cosmetic gap issues and could make the display bond weak or create light leakage.
VHB Strip Description 	VHB Strip ID Number 	Part Number on VHB Strip
Top left 	01 	946-4469
Top right 	02 	946-4471
Right side 	03 	946-4472
Bottom 	04 	946-4468
Left side 	05 	946-4470

Steps for Reassembly

3. The VHB strips have a foam layer (VHB/foam/VHB), with a removable paper liner on the underside, and a clear plastic liner on the top side. The image below shows peeling the paper liner off the underside of the VHB strip.

Steps for Reassembly

4. Before adhering the VHB strips and installing the display, verify that all cables are connected, all screws are installed, and no debris present in the computer.

Steps for Reassembly

5. The rear housing has eight (8) VHB alignment holes. Use them to align the new VHB strips.

Steps for Reassembly

6. Peel the paper backing off of one portion of a VHB strip.

Steps for Reassembly

7. Push the pointed end of a black stick through the alignment hole in the VHB strip. Then point the black stick into the corresponding alignment hole in the rear housing. Keep the VHB strip pulled taut throughout the installation process.

Steps for Reassembly

8. Push gently upward with your finger to adhere the bottom of the VHB strip in place.

Steps for Reassembly

9. Insert the pointed end of the black stick in the other alignment hole and peel the paper backing off.

Steps for Reassembly

10. With the black stick in the alignment hole, position the VHB strip on edge of rear housing. Use your finger to gently smooth the strips. Make sure there are no wrinkles, overlaps or bumps on the strip. Improper installation may result in cosmetic issues.

Steps for Reassembly

Note: There are no guide holes on the VHB strip or rear housing for the bottom. Align the strip carefully by hand.

11. Peel one portion of the paper backing off and starting at one end, carefully making your way across the bottom.

Steps for Reassembly

12. Peel the other portion of the paper backing off, and continue making your way across the entire bottom edge.

Steps for Reassembly

13. Hold the end of the VHB strip gently so it doesn't stick to your hand as you guide it into position. Press down with your finger to adhere it to the bottom edge.

Note: If any VHB strip does not line up correctly, remove it, clean the rear housing, and start again. Make sure there are no wrinkles or exposed sections on the strip. Damage can cause cosmetic gap issues, may make the display bond weaker or create light leakage.