The Hole is optional for a M3 Insert like from Ruthex. The Idea was to get more preasure at the Deskplate. The old one i had before got loose after some time. So I hope this one does not. If you might need another Measure for your Deskplate (mine is 18mm, so the model is made for) you can ask for and I will upload it.
There is no need for support if you lay it on the side. I used 3 perimeters and 40% Infill to get it strong. Mostly I hit it with my chair so I wanted it more stronger ;)
The author marked this model as their own original creation.