HP-41c back case screws holes repair

[tribidouille]

Hello Forum Members,

I was searching how to repair my HP-41c back case screw holes.
As the guides between holes were also broken, none of the solutions I found suited my case.
As you know, the repair pads have to be placed very precisely, otherwise the plastic flex circuit support will not fit in anymore.
So I had to find something with another approach, that's what i am sharing, if one has to do it too, one day.


   
Here are the broken screw holes. I bet it often happens on the hp-41c.
Also 2 of the 4 the middle positioning plastic pieces are broken.
Before to proceed to repair, scratch or file the bottom to remove remaining parts of the screws housings. Obtain a flat (at least not convex) surface.


   
I tried this system by making one myself, but with missing middle positioning pieces, repair pads placing is not precise.


   
So I built a guide (blue) and two simple pads.
This way, repair pads positioning is very precise.


   
First, try the whole process with thin double sided tape:
-Place the pads along the blue guide.
-Delicately pull the guide out.


   
Verify that the plastic flex circuit support comes in place easily, going well down to the bottom.

Max attachments reached. Dare I continue in a next post or are there too many pictures already?
EDIT: pics and text errors