CMG Glass Lens - Solution to iPhone Bezel Coming Off

Blake Jan 11, 2017

Lots of people complain that the glass + HMG(hot melt glue) frame will not properly adhere to the screen, and will easily detach from the screen later. Therefore, more and more third-party manufactures apply cold press technology to glass lens with front bezel and claim it will help getting rid of bezel frame separating from glass issue after refurbishing.

So is this really the case? REWA did a series of test on these two types. Let’s wait and see which one is better.


Home Button Hole Fitness Test

Measure up the diameters of HMG and CMG glass lens with a vernier caliper, and install the same home button to see if it fits. Results: It turns out they are all measured 10.67mm, and fit the same home button properly.

Hydrophobic Effect Test

Apply some water, alcohol, and N-hexane onto HMG and CMG glass lens with bezel orderly and separately. Results: Water, alcohol and N-hexane form a spherical shape to minimize contact with the surface of the glass lens. There is no obvious difference between these two samples on hydrophobic effect test.

Light Transmittance Test

Test the light (visual light, infrared ray 940nm, infrared ray 850nm) transmittance of the two kinds of glass lens separately.


There is still no obvious differences in this round according to the chart. Visual Light

Infrared Ray 850nm

Infrared Ray 940nm

Proximity Sensor Test

Install LCDs with the two glass lens to motherboards. Open up record APP and record a voice demo. Put your hand on the proximity sensor hole while playing back the voice demo. Results: As soon as your hand around the proximity sensor hole, both the two screens shut off. Thus, their proximity sensors perform well.

High-Temperature Test

We laminated LCDs with these two different glass lens. And place the LCD display assembly on the Heating Platform for about 30 seconds at the temperature of 90℃. Results: 30 seconds later, the glass lens & bezel laminated with HMG can be easily separated from the front glass while pulling it by hand. However, for the CMG(Cold Melt Glue) bezel frame, it stays firm on the glass even we pulling harder


Low-Temperature Test

As in the high-temperature test, we laminate LCD with glass lens. And place them into Frozen LCD Separator instead of the heating platform for 1 minute at the temperature of -70℃. Result: Still, the glass lens & bezel laminated with HMG is easy to come off. But no obviously affects to CMG glass lens with the bezel.

Impact Resistance Test

For the first time, we separately dropped one 90g and one 133g metal ball at the height of 90cm. Both of them survived. Then, same balls at the height of 100cm, HMG glass lens failed to survive for the first 90g ball. And CMG glass survived until the 133g ball dropped at the height of 110cm. Results: Cold melt glue frame beats hot melt glue frame in Impact Resistance Test.

Bending Test

Place the sample into the bottom half of the bending machine after modifying sample information, click “go down” button to move down the top head of the machine and push down on the sample separately. Results: According to the real-time graphs and data displayed on the computer screen, the bending strength of HMG glass lens is 43.44kgf, and 44.846kgf for CMG glass lens.


After all the comparison, we draw a conclusion that HMG glass is hydrophobic perfect as CMG glass. Plus, it has excellent high/ low-temperature performance, and can greatly prolong the service life of the glass replacement after refurbishing with its high hardness and good abrasion resistance. With front bezel preinstalled, CMG glass also saves you costs and the process of bezel laminating when refurbishing. So the best choice for glass lens replacement - CMG glass.

You can check our other REWA Screen Repair guides:

Fix cracked iPhone 7 screen ,

Samsung Galaxy S7 edge glass replacement ,

iPhone 7 touch screen not working ,

iPad Air Touch Screen Partially Unresponsive Repair ,

iPhone X Screen Refurbishing – Glass Only Repair ,

iPhone 8 Broken LCD Screen Refurbishing,

Until now, I'm afraid you have made your own decision. If you still have any other questions or are looking for iPhone LCD screens, Glass Glens + Frame or Glass Lens with CMG Frame, please feel free to contact us via or visit the website at . And also testing operation video through our YouTube channel here:

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