GARMIN FORERUNNER 645 Case Replacement for Broken Strap Anchor

ID: 194199

Description:

Steps:

1. GARMIN FORERUNNER 645 outer case replacement due to broken watch band lug. A friend asked me as a favor if I could replace the outer case of his watch because the lug for one of the straps had broken. He provided the replacement part himself, which he bought on AliExpress.

2. To separate the display from the case, we need to create a gap with a utility knife to cut the display adhesive, being careful to insert it only about 2 mm, and use hot air to soften the adhesive. I recommend using one of the Pro Tech Go Toolkit toolkits.
3. Depending on the power of the heat gun, BE CAREFUL not to place it too close, or you will burn your fingers.
4. Other useful tools, such as a thin-blade knife, will also be helpful.

5. We will use one of the tools from the Jimmy toolkit to help separate the two halves.
6. In photo 3, we can see the adhesive residue on the edge.

7. The next step is to disconnect the flex cable that connects the display to the PCB; we will use iFixit Opening Tool to assist us.
8. To remove the 2 screws from the PCB, we will use the T4 TORX bit Pro Tech Go Toolkit

9. Unscrew the 2 Torx screws and remove them with precision tweezers.

10. With the 2 screws loosened, unhook the flex cable that connects the housing to the PCB; use a iFixit Opening Picks (Set of 6) to gently pry it up.

11. To separate the case from the PCB, use a non-metallic tool to gently pry it open. iFixit Opening Tool

12. We see the PCB already removed from the case.

13. Position the PCB in the new case and, by applying light pressure with your fingers in a pinching motion, snap it into place.

14. Press the flex connector into place. Although it is small, it is very easy to position.

15. We replace the screws, since the tip is not magnetized, by placing them with Precision Tweezers Set tweezers before screwing them in.

16. View of the iFixit tools used and other useful tools such as a thin-blade knife.

17. Once the case is assembled, the screen must be attached to the case; I used contact cement, applied with the help of a thin, flat driver bit. Apply a small amount to a plastic surface and apply it to the circle of the case.

18. Once the contact adhesive has been applied around the entire perimeter, insert the flex cable into its socket and carefully close the two halves.

19. Once the 2 parts are inserted, the excess contact adhesive can be removed with iFixit Opening Tool
20. The next step is to firmly clamp the 2 parts together and apply electrical tape, letting it dry for about 12 hours.

21. After 12 hours have passed, we can remove the tape and retrieve the QR code from the case we replaced in order to glue it onto the new one using a cyanoacrylate-type adhesive; in my case, since I had to return it the next day, I cut the electrical tape and did it immediately.

22. To attach the QR code plate, apply a drop of quick-drying glue.
23. Leave the watch taped for 12 hours so the contact cement bonds properly.
24. END of guide.