Lower Post repair
We have gone through many interations, both to the pieces used and the process. We think we have found a process that is durable, easy to apply and works all the time. You don't need to have steady hands to succeed!
Let's assume that both posts are broken or cracked. The effect of this cracking is that the screws do not do their job. Usually, using longer screws may help, but this typically is short lived since the cracks will continue downwards. Once this pressure is softened, the calculator doesn't work anymore. The solution is to repair the broken posts.
Old methods to repair broken post is to glue them (but this doesn't hold together too long) and to tie them down with very small gauge copper cable, applying pressure so that it holds together. This may solve some cases, but not when the screw path has been destroyed - maybe due to strong tightening of the screws.
Other repair methods have been proposed, including drilling down the screw and placing in its place a cylinder with screw path, glued in place. We tried this method but there was a problem: the torque used to screw resulted in cracked glue and the cylinder separating from the substrate - every time.
Our method was devised with three goals in mind:
The piece that we have designed requires drilling the old posts to the keyboard ciruit level, taking care of leaving the hole clear. The design on the piece is such that the pin will be glued to the inner part of the rest of the screw post; and the surface of the piece can be glued to the keyboard circuit, so that the torque on the substrate is avoided (it also helps that torque is also resisted by the other post, when using the full piece)
When gluing the piece, there are several precautions that need to be taken:
We recommend to repair both posts at the same time. However, if you are confident on the resistence of the other post, you can use our 1-side piece. As it is symmetrical, it can be used for both posts, just twisting it 180º. Using the full piece, the other post side does not need to be glued - the torque resistence is done by the post itself over a much longer distance.
Alternatively, you can cut the other side of the 2 post piece with a tweezer and glue in place the rest of the piece.
Upper post repair
Same procedure. You need to use our upper post repair piece. Same precautions apply - be careful of covering with tape the zebra part; and also the pin holes of the keys, just in case.