Breaking the iMac stand hinge makes the computer unusable and is a more frequent occurrence than you might think.
Its repair, if performed by a specialized center, can cost a lot because it involves a fairly complicated and long mechanical intervention. If, as in my case, you have a rather old iMac (late 2012) or otherwise largely out of warranty, it may be convenient to try to solve this problem with an external solution that allows to support and adjust the monitor in multiple positions, for adapt to various viewing angles.
I designed this system based on an open threaded tube with its corresponding ring nuts, which, thanks to its diagonally cut end, ensures different inclinations of the screen with respect to the horizontal plane of the iMac stand.
I have threaded a fairly large section of the tube so that it fits in the best way to get the required position. The tube is inserted directly into the original hole of the stand used to pass the power cable and is tightened by the two opposing rings. The tube is cut lengthwise to facilitate installation and passage of the original power cord.
This solution guarantees a good solidity and an absolutely repeatable position of the desired screen. If printed with a bright color it can give our iMac a rather pleasant vintage look.
I am not aware if the 21 "iMac version has an equal hole in the stand or smaller, but in the case of small diameter variations I think we can simply resize the original design by using any slicing program.
Would you consider a small donation? This would help me to create new things for you too!
print the tube vertically with 10mm of brim without any support.