2011 Imac 27 Touchscreen!

[Lxixboss]

As I was looking through my local "used stuff for sale" site, I came across a fellow selling an LG 27-inch panel to which a touchscreen overlay had been added. He mentioned that it was the same screen that was used in 2009-2011 Imac 27's. Knowing that a touchscreen option is on many Mac users' wish lists, I decided to investigate. I quickly found that the unit he had was a PQ Labs unit. Upon perusing their website, it seemed that this had to be a G4S since that is the only 27" model the site talks about. A quick mosey over to their Support and then Downloads section revealed that THERE HAS BEEN AN OSX DRIVER FOR THIS UNIT ON THEIR WEBSITE SINCE DECEMBER 2016!!! Seeing that the seller was asking $80 for this unit, I decided to buy it on a lark (and I talked the guy down to sixty-five). This unit is USB powered so, when I got it home, I downloaded and installed the software, I plugged the unit into one of my Imacs' USB ports... AND IT WORKED!!!! ARE YOU FRIGGIN; KIDDING ME??? WOO-HOO!
Back to Earth... One funny thing about it is that the unit used absolute referencing... unlike a trackpad or mouse. So, the habit of lifting the mouse off the table, moving it and then setting it down again to move the cursor has to be broken. So, if you want to click on something in the top right-hand corner of the screen, that is the spot you have to touch on the touchscreen overlay.
Right now, it is still attached to the second 27-inch LCD panel which is not hooked up to anything. The overlay is attached to the LCD panel with two-sided tape. I have to decide whether I unstick the overlay from the panel with a hair dryer and plastic spudgers, credit cards, etc. (and risk breaking it), or whether I transfer the mounting brackets and cable from my existing panel to this one and install it into the Imac. If I do the former, I think I can stick the touchscreen overlay to the glass screen cover on the Imac. Conversely, if I do the latter, I think I can fit the panel and overlay into the Imac's chassis and even be able to install the eight Torx 10 screws that secure the panel to the chassis. Of course, I would not be able to use the Apple glass overlay and I would have a 1/4" to 1/2" gap on three sides to fill in with something (perhaps Canadian Tire automotive molding???... although I don't want this to look like a K-Tel product.)
At any rate, I am completely stoked with this. If anyone has any ideas, experience, expertise, etc. to share, I would be greatly appreciative. If I judge that there is an interest, I will chronicle my progress (or disasters) in this matter.

 

[Lxixboss]

So, I took the 27-inch LG panel to which the touchscreen overlay was glued and hooked it up to my 2011 Imac 27. Sadly, the right 20% of the display had vertical lines going through it. I rechecked the connections, changed the LVDS, V-sync and temperature sensor cables, all to no avail. I was able, however, to ascertain that the overlay worked. When I put the original panel back in, all was good (whew; I was a teeny bit worried that I might have fried the GPU). Anyway, that made my decision to "unglue or leave glued" easy. So, I took out my wife's hair dryer and various spudgers and cut-up credit cards and proceeded to separate the touchscreen overlay from the defective LG panel. I was very careful and it took about an hour to free the overlay and another hour to peel the gooey residue from the side of the overlay that had been against the LCD. I then wondered about how to attach the overlay to the glass panel on the Imac. I felt that, for now at least, the idea of using double-sided 3M tape to semi-permanently attach the overlay to the glass which covers the 2011 Imac didn't appeal to me. So, I raided my wife's sewing basket and got some velcro (the type with the tape on one side). I stuck one strip of the "hook" part of the velcro equation to the very top of the Imac housing (leaving a gap for the mircrophone) and another to the top of the touchscreen overlay's frame. I then cut 10 2" strips of the "loop" part of the velcro and used them to join the two aforementioned velcro "hook" strips. I then added small strips to the very bottom of the overlay on the right and left sides of the Imac (to prevent the bottom of the overlay from swinging outward when the screen was tilted forward). After that, I hooked up the USB cable, calibrated the overlay and, BOOM, Bob's your uncle! Works like a charm! Now, I don't know if I actually like using the Imac with a touchscreen but it was never about that. It was more about the challenge of doing it. Now it's done so, off to the next challenge... getting my 2007 Mac Pro 2,1 to play nice... but that's another story.

 

[mmomega]

I still love reading when someone just mods the heck out of something. Good job.

This has also been a thing for quite a while.
http://www.cultofmac.com/177087/this-200-accessory-gives-your-imac-a-touchscreen/ was a one of the first things I found with a search. I remember reading about this years ago.
I've never enjoyed the idea of a touchscreen desktop, personally. I remember when SAM's club had one of the first touch screen all in one HP computers and within a couple minutes arm fatigue and fingerprints show why this isn't a more widely spread thing.
It has it's niche like anything else but for this guy I'm out on it.

But again good job on making it work.