How to properly paste the protective glass on Xiaomi Redmi 9: instructions with photos and tips

The security glass on Xiaomi Redmi 9 is not a luxury, but a necessity. Even with careful use of micro-damage screen is inevitable: sand in your pocket, accidental fall or scratches from keys. But many users face problems when installing: bubbles, dust under the glass, improper positioning. This article will help avoid typical errors and install protection so that it lasts for years.

The Redmi 9 is a special feature of the 2.5D-The rounded edges of the screen, which make it difficult to fit, and the standard glass often doesn't cover the entire surface or flakes off at the edges, and we'll figure out how to choose the right option, prepare the screen, and fix the glass without defects. And we will also tell you why cheap kits from China can turn into additional costs.

Why you should wear a protective glass on Redmi 9

The Redmi 9 screen is made using IPS LCD technology with HD+ resolution (1600×720) and a diagonal of 6.53 inches. Despite its strength, it is vulnerable to:

🔹 Scratches from metal objects (keys, coins, belts) even microscopic lesions eventually turn into noticeable grooves.
💥 Fall impacts: Gorilla Glass 3 (installed in the model) withstands head-on collisions, but lateral loads often lead to cracks.
🧴 Chemical damage from creams, alcohol-containing liquids or household chemicals, which eventually erode the oleophobic coating, making the screen sticky".

Not only does the protective glass prevent these problems, it also keeps the screen tactile, and quality models (such as those with 9H hardness) feel almost the same as the original glass.

📱 Reduce glare in the sun due to the antireflex layer.
👆 Do not interfere with the work of the fingerprint scanner (if it is located under the screen).
🔄 Easy to replace when damaged – cheaper than repairing the original display.

⚠️ Warning: If your Redmi 9 already has deep scratches, the protective glass will not hide them, but will only emphasize them.

What kind of protective glass to choose for Xiaomi Redmi 9

There are hundreds of options on the market, from unnamed Chinese to premium Belkin or Spigen, but for the Redmi 9, three criteria are important:

The edges are covered. 2.5D-And if you're bending, standard glass doesn't close the screen completely "3D".
Thickness: Optimally 0.2-0.33 mm Thin glasses (0.15 mm) are worse at protecting against impacts, and thick glasses (> 0.5 mm) impair sensitivity.
It's oleophobic, and without it, there's going to be greasy marks on the glass that are hard to wash off.

The best options for price/quality ratio:

Model	Type	Firmness	Pluses	Cons
Nillkin H+ Pro	3D Full Cover	9H	Full coating, anti-reflective coating, complete with tools	More expensive than analogues
Xiaomi Original (in the box)	2.5D	9H	Perfectly fitted to the model, inexpensive	Does not cover the edge, quickly erases the oleophobic layer
Spigen Tempered Glass	2.5D	9H	High strength, retains sensitivity	No full coverage.
AmFilm Ultra	3D	9H	Thin (0.2 mm), with self-centering	It is difficult to find in Russian shops

Avoid UV-adhesive glass (requires an ultraviolet lamp to install) and hydrogel glass (they are soft and scratch quickly). Also check the package: the kit should contain wipes, a dust collector and a positioning sticker.

📊 What kind of protective glass do you prefer?

Budget (up to 300) ₽)

Mid-segment (300-800) ₽)

Premium (from 800) ₽)

I don't glue protective glass.

Preparation of the smartphone before installation

90% of the failures are due to poor screen preparation, and even one speck of dust under the glass will ruin the whole thing.

Turn off your smartphone and let it cool (if it was heated)

Remove the cover and film (if any)

Wipe the screen with a wet microfiber wipe

Remove glue/fat residues with an alcohol napkin

Check the screen under bright light for dust.-->

Pay particular attention to:

🔍 Dynamics and sensors. You can't cover them with glass. You usually have a clipping template in the kit -- use it.
🧴 Remains of old glue. If there was glass before, remove the sticky layer with isopropyl alcohol (not acetone!).
🌡️ Temperature: Glue on glass is better at room temperature (20-25)°C) Do not install in the bathroom or on the balcony.

If there are deep scratches on the screen, they can be masked with GOI paste polishing (but this is a temporary solution).

⚠️ Warning: Do not use household alcohol for cleaning - it contains additives that leave the film. Only isopropyl alcohol 90%+ or special napkins for optics.

Step-by-step instructions: how to glue a protective glass

The installation process takes 10-15 minutes, but requires care.

Unpack the glass and check the equipment. Make sure it is not chipped (light the flashlight at an angle).
Stick a positioning frame (if included) to help align the glass.
Remove the protective film from the glass on one side only (with glue).
Carefully apply the glass to the screen, starting at the top. Don't push it, it will lie down under the action of the glue.
Remove the bubbles with a credit card or a special scraper, moving from the center to the edges.
Let the glue hold for 2-3 hours. Don't use your phone at this time.

Critically, on Redmi 9, because of the rounded edges, the glass can move away from the sides, and to avoid this, warm the edges with a hair dryer (40-50°C) for 10 seconds after installation, this activates the glue.

If the bubbles do not disappear, they can be eliminated as follows:

💨 Small bubbles (up to 1 mm) often disappear on their own after 12–24 hours.
🔧 Large bubbles gently prick with a needle and press the glass.
🔄 Dust under glass is an excuse to glue it. Don't try to smear the pollution.

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If the glass has shifted during installation, do not try to move it with your fingers - so there will be traces. It is better to gently tuck it into a thin plastic map and glue it.

Common Mistakes and How to Avoid Them

Even the most experienced users sometimes miss out, and here are the most common ones:

Mistake.	Effects of consequences	How to avoid
Installation in a dusty room	Under the glass are the mowings that scratch the screen.	Close the windows, use the dust collector from the kit
Touching the sticky side	Fat from the fingers worsens the grip, there are divorces	Take the glass by the edges or use tweezers
Use of household tape for fixation	The glue from the tape remains on the screen and spoils the oleophobic coating	Use only the original frame from the set
Pressure on glass during installation	There are “rainbow” divorces due to uneven distribution of glue	Just put the glass on and let it "look down" on its own.

Another common problem is that the edges detach a week after installation, and this is because of:

🧼 Poor screen cleaning (residues of fat or cream).
🌡️ Temperature changes (for example, if the phone was lying in the sun, and then hit a cool room).
📱 Use thick covers that press on the edges of glass.

⚠️ Warning: If the glass starts to play when pressed (bend and come back) after installation, it is a sign of insufficient pressure during installation.

Care for protective glass: extending the service life

Even the strongest glass will last longer if you follow the simple rules:

🧼 Clean the screen with only microfiber cloth (no pile) and special wipes. paper towels scratch.
🚫 Avoid aggressive remedies: acetone, bleach, glass washing fluid, which destroy the oleophobic coating.
📱 Remove the cover when cleaning - dust accumulates under it, which then falls under the glass.
🔋 Don't put your phone down on hard surfaces (table, windowsill). 9H-glass can crack from a point impact.

If the oleophobic coating is erased (the screen becomes "sticky"), it can be restored:

Buy a wax-based glass polyrene (e.g. Liquid Glass Screen Protector).
Apply 2-3 drops on the screen and evenly spread with microfiber tissue.
Polish in circular motions until shine. The effect lasts 1-2 months.

The average life of quality glass is 6-12 months, and then it is better to replace it, because microcracks reduce strength.

What to do if the glass cracks?

If the crack is shallow and does not interfere with use, you can temporarily paste it with transparent tape (for example, Scotch Magic Tape), but this will not protect the screen from further damage. The best option is to replace the glass as soon as possible, since chips can injure your fingers or scratch the original display.

Frequently asked questions

Can I put a protective glass on an already cracked screen?

Technically, yes, but it's a temporary solution, because glass doesn't hide cracks, it just prevents them from spreading, and if the screen is badly damaged (a grid of cracks, chips), the glass may not stick to the surface because of the roughness, so it's better to replace the display in the service first.

Why does the glass interfere with the fingerprint scanner after installation?

This happens if: The glass is too thick (> 0.33 mm) -- the sensor doesn't recognize the finger, there are bubbles or dust left under the glass above the scanner, you use a non-original glass without a cutout under the sensor, the solution: glue the glass, select a model marked "Compatible with In-Display Fingerprint".

How to remove old glass, if it is glued to "dead"?

If the glass doesn't go around the corner, use this method: Heat the screen with a hair dryer (50-60°C) for 30 seconds, it will soften the glue. Put a plastic card (not metal!) on the glass from any angle. Pull it carefully, holding the phone. If the glass breaks, remove it in parts. Remove the glue residue with isopropyl alcohol. Don't use a knife or blade - they will scratch the original screen!

How much does it cost to install a protective glass in the service?

Prices vary by region and glass model: Budget glass (up to 300) ₽) — installation 150-300 ₽. Premium glass (from 800) ₽) — 300-500 ₽. 3D-Full-coated glass – up to 800 ₽ But many services refuse to glue the glass that the customer brought in and offer only their own.

Can I wash my hands and use my phone immediately after installation?

Undesirable. The glue on the glass will finally polymerize after 12 to 24 hours. At this time: Do not wet your hands before using the phone (moisture can get under the edges of the glass); Do not put the phone in your pocket with keys or coins; Avoid sudden temperature changes (for example, do not take the phone out into the cold immediately after installation).

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The key to installing a protective glass on a Redmi 9 is to carefully prepare the screen and be careful, and even the most expensive glass will not save you from bubbles if there is dust under it, and if you doubt yourself, you should trust the process to a professional.