nice work on making so many! Ive also been making some prototypes of shoulder and arm joints but you’ve cut out quite a bit more pieces than me already lol.
It looks like your holes are very straight and square. Do you have any tips? Every now and then my holes/pins turn out at an angle and i have to re-cut the piece.
Some of the holes aren't flush since I had to re-drill the second pla plate. Normally I would drill on both pla plates first then reshape the pla plates which should make the holes align perfectly. However, since I will cement the runers inside the inner frames that kind of precision isn't necessary for this mod.
As for the holes, I always mark the center first before drilling it. The mark should at least help your drill bit get a grip on that first touch. Then I just keep my hands perpendicular with the surface.
If the holes you're making are long/deep, you might wanna stop now and then to check if they are straight.