[Nexus 4 Q&A, Help & Troubleshooting] pflatlyne:
I got my hands a E970 screen with a cracked digitizer. I hoped to use it to replace my cracked E960 screen,with a cheap 30 buck digitizer. So I carefully checked the pin-outs and it looked good. I then plugged it in and what do you know,worked just fine. So for what its worth,if its useful to anyone else,the LCD screen from an E970 will in fact work in an E960. Unfortunately it didnt work out. The screen,like the nexus 4 display,was glued t the front frame. I tried getting it out and ended up destroying the lcd. However,I did experiment with heating the front and separating it with a molybdenum wire. That part seemed to go smoothly. If anyone else has to do this,heres my best suggestion. Get some sandpaper,perhaps 80 grit and glue it to a board. Then sand the edge,moving parallel to the plane of the screen until you have ground away the frame and exposed the edge of the glass digitizer. Repeat on all four sides. This way you should be able to get to the adhesive under the digitizer without further cracking any glass. Remember,the front of the digitizer is cracked,so the lcd is vulnerable. I would get a piece of window glass and cut it to about the same size as the glass digitizer. Then used adhesive transfer tape to bond it to the front cracked glass.

Keep in mind,Ive not separated one successfully yet,so this is a combination of a report of my experiments and my educated guess on how to proceed in the future. It goes back to a previous attempt I did on a broken LCD. I conjectured that if I were to separate the plastic digitizer from the FRONT glass,I could more easily peel it away from the LCD. SO I took separated about a mm of the digitizer from the front glass. Then I ran a qtip dipped in acetone along the edge. The acetone was drawn into the gap by capilary action. I then waited a few minutes,repeated the acetone dipped qtip procedure,and then carefully slid the corner of the foil coated plastic package of a nicotine patch through the gap. The packet is very very thin,way thinner than a credit card,but very stiff. It easily removed another mm or so of the adhesive,and better still,left a gap,so that your not forcing the display to bend. This went well until I got near the last half inch of a shard of glass,about 1/3 of the way up the display. At that point,I applied a bit of upward force and that shard,about two inches long,with a sharp point,held only by a the last half inch by perhaps 1/3 inch section of adhesive shattered the LCD under the point. The lesson learned is,a cracked digitizer is going to have this lever effect on the shards that crack the lcd with a tiny amount of force due to the combination of the long lever arm and sharp point. So the glass is to hold that all together and keep it from doing the lever thing.

My experience tells me that ,yes,those techniques you see on the internet with the credit card and the heat gun MIGHT work,but your going to need a lot of skill. And that skill is developed by trashing DOZENS of LCDs. And its still not going to be 100%. Probably no more than 50%. My guess is that these were developed by people who repair these for a living. If you do,then you probably have a big box of broken displays. Some only have broken digitizers,some broken LCDs,and you think "If I had a way to reuse some of these parts,I could make a bunch of extra money" so you start with the broken ones,and then when you get something that works,even 50% of the time,you can make 50 bucks or more extra profit per screen you can fix,from parts that were previously worthless junk to you.

But I want something 100%,not for my nexus,but because more and more phones are made like this,and in the future they all will be. So I want to make a procedure that will fix it all the time. So far,I suspect that you have to choose one part to save. Either the frame or the LCD digitizer stack. I may try working around the edge with a plastic tool and heat with a glass bonded to the front and see if I can get the glass free of the frame without destroying the LCD,but Im not optimistic,first Id like a sure fire way to save an LCD.

My feeling is that if you bond the front glass to a ridged substrate,you can then use the sandpaper to grind the edge away. If you do it parallel to the plane of the screen,it should be very gentle on the display,avoiding any damage. Then you can perhaps with the aid of heat,cut the digitizer away from the frame. Im thinking at this point,you need a screen separator.

So Im going to make one. My plan is that I will make a device from plywood. It will have a backing and a part that slides. The part that slides will have a heated piece of aluminum with a thermostat that holds it at 175F and an inductive heating coil behind the aluminum. This "carriage" will slide back and forth,and there will be an guide that will constrain its motion to one axis. The "carriage" will actually be made from two blocks,one that will be in the guide,then a second that bolts to that,using some studs,and washers and wing nuts. Between these two plywood layers,I will uses sheets of paper as shims to adjust the height so that a 0.08mm molybdenum wire (I have 100' of it I got off ebay) is at the right height to separate the screen. The screen will be stuck to the glass with adhesive transfer tape,the edges ground away,then mounted to the separator with adhesive transfer tape,and shimmed to the right height. I can then heat it to temperature (the glue *I* use SHOULD be strong enough to hold it in place,if not,I just buy one of the higher temp adhesives. I can then separate the digitizer from the front glass AND the frame. At that point,the LCD should be free of the frame. Now,if the digitizer is OK,I can simply ,carefully clean the adhesive off of it and repair it using a 12 dollar front glass.

Some people use optically clear adhesive that is uv cured,because its easier to get a bubble free bond without a vacuum oven or autoclave so I will just use an optically clear adhesive transfer tape. I however have access to a vacuum oven at work,so I'm good to go. Even if I did not,I suspect that there are other options. I might try one of those vacuum storage containers they sell at target that go with those "food saver" vacuum packers. (I want one anyway to freeze food in,very handy. Buy 40lbs of chicken breasts when they come on sale for 1.89 a lb and freeze them! Pays for itself in no time) My hope would be that ,perhaps of first heated to say 180F or so,then placed on paper to avoid melting the plastic container ,you and a vacuum pulled,it would remove the bubbles. But I have access to the oven so I don't care much about that.

If not,then I can probably make sure the wire is on the other side of the digitizer and separate it from the lcd instead. Then the same procedure can be used to bond the LCD to a new digitizer/glass assembly. But first I need to find some more broken LCDs to play with. But hopefully my experiences will help others in their quest. The end result of what I have determined though is,Im going to have to make the separator,becuase while its obvious that its POSSIBLE without it,its just not reliable or practical.