If you attempt to cut the glass yourself you will break the screen protectors.It is difficult to cut Tempered glass because it is made by heating regular glass to high temperatures and cooling it while applying pressure to strengthen it.If you want to un-temper the glass or use a laser cutting machine, you have to buy thousands of dollars worth of equipment.If you can't simply return the old screen protector or replace it, there are two options that may work.
Step 1: Put your phone upside down.
Put your screen protectors on your desk or table.Take the phone out of the case and put it upside down.The edges of the protectors should be parallel to the phone's edges to make cutting easier.Measure the dimensions and draw them on the screen protectors, if you want to put it on something other than a phone.
Step 2: Use a thin permanent marker to outline the phone.
There is a fine-tipped permanent marker.Carefully outline your phone with the edges being a straight edge.If you keep the plastic part of the marker against the phone, you won't get ink on it.To transfer the size you need to cut on to the screen protector, cover the entire outline of your phone.If you have a home button, add a small notch at the bottom.The notch will be harder to cut out.
Step 3: Wear thick gloves, a dust mask, and protective eyewear.
It is important to take the proper precautions to avoid cutting yourself, regardless of how you are cutting the glass.Throw on a long sleeve shirt and get some protective goggles to keep your eyes safe.If you cut the glass underwater to reduce the amount of stress on it, you probably don't need to protect your lungs.If you are going to trim the screen protector down with a diamond file, you need a dust mask or respirator to avoid inhaling the dust from the glass.
Step 4: Warm water can be used to fill a bucket or bin.
Take a container large enough for you to submerge both of your hands, your screen protectors, and a pair of scissors.If you have something like that, a box of that size should be enough.Warm water from your tap can be used to fill the bucket.
Step 5: Take some scissors and submerge the screen.
A pair of scissors isn't going to work for this.The scissors have sharp blades.If you want to submerge the scissors in the water, hold them in your dominant hand.Hold them below the surface for 2–3 inches.Don't take your gloves off.Gloves in water are a key part of staying safe.
Step 6: Carefully trim the first side of your outline.
Start on the side of the screen that protects it.Keep your nondominant fingers at least 2 inches away from the cutting line.Carefully cut along the line that you drew.Slow down and make sure you don't put too much pressure on the screen at once.It is thought that the water reduces the strength of the glass and makes it easier to cut.The feeling of cutting glass underwater is compared to cutting cardboard.
Step 7: Cut the additional sides by rotating the screen underwater.
Once you have trimmed the first side down, turn the screen protectors to the next edge and cut the second side out.For the rest of the screen protectors, repeat this process.Cut slowly and make sure you don't break the screen.If you have a notch for your home button, use the blades that are closest to the handle, not the tips.
Step 8: To dull the edges underwater, use a diamond file or dremel.
Pick up a tool with a buffing tip.Use gentle back-and-forth strokes to remove the screen protectors from each side of the file.Remove any loose shards when you smooth the cuts out for each side.If you are using a dremel tool, hold the buffing tip underwater.To buff it out, turn the tool on and run the tip around the screen.A diamond file is a long piece of metal with a textured edge used for sanding hard materials.Similar to sandpaper, diamond files have different grits.You can use the finest grit to do this.A power tool with a tip that spins is called a dremel tool.It is used to trim materials.Only submerge the rotating tip in the water if you use a dremel tool.
Step 9: There is a screen protectors near the edge of the table.
There is a sheet of cardboard near the edge of the table.Put your screen protectors on top of the cardboard and hold one edge off the table.If the screen breaks, place another sheet of cardboard on top of it to keep shards of glass from flying.
Step 10: The diamond file should be parallel to your outline.
You have access to the finest diamond file.Place your nondominant hand on the top of the screen.Hold the file against the side you are sanding.Carefully move the file back and forth.It may take a few minutes to remove the glass from the screen.You have to be very careful while doing this.The screen protectors may shatter if you apply too much pressure.It will take a long time since you can only work in 2 inch sections with the small dremel bit.Your line probably won't be as clean.
Step 11: Continue filing the screen protectors until they match your outline.
If you want a new side to rest over the edge of your screen protector, you need to lift the cardboard up and rotate it.You should file this side the same way you did the first side.Continue this process until you have removed all of the excess glass.Since the diamond file is doing this for you, you don't need to sand the edges down.