I've been working on my triptych, yet forgot to upload the pictures.
The gessooing went well, the triptych works well yet of course, in this version the painted layers would be pressed against each other.
The version for which I needed the drill will have the frames separating the painted surface from each other. The hinges will be screwed into the frames, at four points. I also made a re-design so that the inside image will be one complete painting instead of having the frames split it into three parts by the framing.
I begin to realize I am sort of delving into new territory here since I cannot find a lot of tutorials on the stuff I want to do. Which means that it is either impossible or few have done it before.