Why the glass on Xiaomi smartwatches is going away and how to fix it
The glass on Xiaomi’s smartwatch is one of the most vulnerable parts of the device, and even when used carefully, it accumulates over time, microcracks appear, or it begins to peel off altogether. The causes range from factory defects (especially in early Mi Watch Lite batches) to mechanical damage from falls. But most often the problem lies in the drying of the factory glue — after 1.5-2 years of operation, the adhesive loses elasticity, and the glass begins to walk when pressed.
You can restore the leakage yourself, but it is important to consider the nuances: for example, for the Xiaomi Watch S3 with an aluminum body and the Watch 2 Pro with steel, different types of glue are required. The wrong choice of material or technology will lead to re-detachment in a few weeks. In this article, we will analyze all the stages of the process, from diagnosis of the problem to final polishing, so that the result will last no less than on the new watch.
Before you start repairing, make sure that the problem is the unstuck glass, not the damaged display. Do the test: leicht press the glass at the edges. If the image on the screen is distorted ("waves" appear), then the glass has moved away from the display and needs to be repainted. If you press nothing happens, but cracks are visible, you will most likely need to replace the entire module.
What tools and materials will be needed
To reglaze glass on Xiaomi watches, you need a specialized set of tools. Don't try to do "at hand" - this can damage the plumes or get dust under new glue.
- 🔧 Plastic blades (0.2-0.4 mm thick) - for careful slashing of glass. Metal tools will leave scratches on the body.
- 🧴 Special glue: B-7000 — Universal option for most models, except the Watch 2 Pro (there you need a stronger composition). LOCA UV-glue - for professional gluing with UV curing (requires lamps). 3M VHB — double-sided tape for temporary fastening (not suitable for permanent use!).
- 🧼 Cleaners: isopropyl alcohol (90%+), scotch-free wipes, scotch to remove dust.
- 🔦 UV lamp (if you use it) LOCA-glue) or hair dryer B-7000.
- 📏 Calibration gaskets (optional) - for uniform pressure distribution during gluing.
For models with rounded glasses (for example, Xiaomi Watch S1) will additionally require a template for cutting glue — it can be made from dense paper along the contour of the original glass. Also prepare tweezers for working with fine parts and a magnifier — it will help to control the absence of dust before gluing.
Preparation of the clock: disassembly and cleaning
The first and most important step is neat disassembly. Most Xiaomi models have glass attached to glue without any additional latches, but the Watch 2 Pro has hidden clips around the perimeter of the body, and if you don't notice them, you can damage the plastic side of the glass when you smack it.
Disassembly instructions:
- Turn off the watch and take off the strap.
- Plug paint tape on the glass - this will prevent scratches from appearing when underdog.
- Heat the body with a hair dryer (temperature 50-60 ° C) for 2-3 minutes - this will soften the old glue.
- Insert a plastic blade into the gap between the glass and the case (start at the corner where most dust usually accumulates).
- Carefully drive the blade around the perimeter, gradually lifting the glass. Do not apply force - if the glass does not lend itself, warm up the case again.
After removing the glass, both surfaces must be thoroughly cleaned:
- 🧽 Remove the remnants of old glue from the case and glass with scotch or wooden stick (metal scratches!).
- 🧴 Wipe both surfaces with a napkin soaked in isopropyl alcohol. Repeat 2-3 times.
- 🔍 Check under the magnifying glass - there should be no villi or glue particles on the surfaces.
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If there is moisture under the glass, place the watch in a sealed bag with silica gel for 12 hours before gluing, which will prevent condensation under the new glass.
Choosing adhesive: what is best for your Xiaomi model
The type of adhesive is responsible for up to 80 percent of the success of the repair, and the wrong choice will lead to re-detachment or bubbles.
| Model clock | Recommended glue | Time of curing | Features |
|---|---|---|---|
| Mi Watch Lite | B-7000 | 24 hours. | Thin layer (0.1 mm), does not require a UV lamp |
| Watch S1/S2 | LOCA UV-glue | 5-10 minutes under UV | You need a precise dosage, otherwise there will be bubbles. |
| Watch 2 Pro | 3M 467MP + B-7000 | 48 hours. | Double-layer application: first scotch, then glue |
| Watch Color 2 | B-7000 with hardener | 12 hours. | It requires uniform pressure when drying. |
For the Xiaomi Watch 2 Pro with sapphire glass, it is better to use a combined method: first stick a thin layer of 3M VHB 467MP (0.2 mm), and apply the B-7000 on the top. This will provide reliable fastening and protection from moisture. For other models, one layer of glue is enough, but it is important to observe the thickness - excess will lead to the extrusion of excess under pressure.
⚠️ Warning: Never use superglue (cyanoacrylate) or epoxy resin! These compounds crystallize over time and can damage the display when dismantled, and they don't provide tightness, which will cause moisture to enter the glass.
Step-by-step instructions for gluing glass
When the surfaces are cleaned and the glue is matched, you can start gluing.
Both surfaces were cleaned of dust and fat|The glue is applied with a thin, uniform layer|Glass aligned in the center of the body|Fixing tools (strubcines/loads) ready)-->
- Applying glue: For the B-7000: squeeze a thin snake around the perimeter of the body at a distance of 1-2 mm from the edge. Do not apply glue to the center - at pressure it will be evenly distributed. For LOCA: drop 2-3 drops in the center of the body and spread glass (sandwich method).
Installation of glass:
Carefully place the glass on the body, tagged (if any), press the center so that the glue starts to spread. Then check for no bubbles — if they appear, slightly move the glass to the side and press again.
Fixing:
Place the watch under load (for example, a book weighing 0.5-1 kg) or use soft-laid rods. LOCA-glue is additionally irradiated with a UV lamp (365 nm) for 5-7 minutes.
Drying:
Leave the watch under pressure for the time indicated in the table above. To speed up the process (except LOCA), you can warm up the body with a hair dryer at 40 ° C for 10 minutes.
After drying, check the tightness: hold the watch to bright light at an angle. If there are gaps on the edges, then there was not enough glue, you will need to re-do the procedure. Also test the sensor: swipe your finger at the edges of the screen. If the response is delayed, maybe the glue hit the plumes, in which case you will have to take apart the clock and clear the contacts.
What to do if the glue hits the display?
Frequent Mistakes and How to Avoid Them
Even if you follow the instructions, you can make critical mistakes that will negate the effort.-5 Failures and ways to prevent them:
- 🔴 Bubbles under glass -- caused by uneven distribution of glue or air intake. Solution: apply glue from center to edge and use a vacuum bag to remove air before fixing.
- 🔴 Glass walks after gluing, because there's not enough glue or surface cleaning, so you can increase the glue by 10 to 15 percent and use an acetone-based degreasing agent.
- 🔴 Poor tightness - most commonly seen in the Watch 2 Pro due to improper body preparation.Solution: Warm up to 50 before gluing°C for better adhesion.
- 🔴 The glue has stepped over the edges -- aesthetically ugly and can interfere with the strap's putting on. Solution: Remove the excess until cured with a cotton swab dipped in alcohol.
- 🔴 The sensor stopped working, the glue hit the plumes or contacts, solution: only complete disassembly and cleaning with alcohol (in 20% of cases, a plume replacement is required).
Pay special attention to the Xiaomi Watch S3 — this model often leaves not the glass itself, but the protective film underneath. In this case, just glue the film, not touching the glass. Use ultra-thin double-sided tape (0.05 mm) and warm the watch with a hairdryer before gluing.
⚠️ Warning: If the watch starts to overheat or discharge quickly after repair, disassemble it immediately! This is a sign that the glue has hit the battery or motherboard.
Final polishing and seal check
Once the glue is cured, there are two critical steps: polishing the edges and a moisture test, and even if the glass is glued perfectly, sharp edges or microcracks in the glue will eventually lead to re-detachment.
Instructions for polishing:
- Examine the edge of the glass under the magnifying glass. If there are glue protrusions, remove them with a plastic scraper (not metal!).
- Apply a polished paste (such as GOI) to the edge of the glass and polish the soft cloth with circular movements.
- Wipe the body with a lilaless napkin soaked in alcohol to remove the remnants of the paste.
To check the leakage:
- 💧 Immerse the watch (without a strap) in warm water for 1-2 cm for 5 minutes. If condensate droplets appear under the glass, then there are microcracks in the glue seam.
- 🌡️ Place the watch in the freezer for 15 minutes, then take it out and check it under light.
If the leakproofness test fails, repeat the gluing procedure using hydrophobic adhesive (for example, Permatex 81756). For models with an official rating of 5 ATM (Watch 2 Pro, S3), it is recommended to additionally apply the sealant at the junction of the case and glass after repair.
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UV adhesives (LOCA) are 30 percent more reliable than the B-7000, but require precise dosage and a UV lamp. For beginners, it's better to start with the B-7000, which forgives minor errors.