We all know that there are many M2.5x6 BHCS Machine Screws in the CyberBrick kit.  The model designed for the CyberBrick kit always uses these screws for fixing parts.

But the screw hole is very tricky to handle. Usually, we use a round hole close to the diameter of the screw, as the picture below shows.

But after printing, the round hole is either too big or too small. If it's too big, the screw can't tighten. If it's too small, it's hard to screw in and always squeezes out scraps, as the picture below shows. Especially when you use an electric screwdriver, the heat generated by the high-speed friction melts the hole and strips the screw easily.

There is a new screw hole structure released with my new CyberBrick project, which can help to solve this problem.

I modified the screw hole from round to a rhombus. For M2.5x6 BHCS Machine Screws, I leave a diagonal 3mm rhombus hole. When the screw is in, the 4 faces of the rhombus overlap with the screw(transparent red area), to keep the screw firmly fixed. The 4 corners of the rhombus are hollow, which can contain the squeezed scraps(Blue area).

It's also friendly to electric screwdrivers because it has hollows that can cooling. The shape of the rhombus is easy to print, no matter how you arrange the parts horizontally or vertically.

Try it, I'm sure you can improve the assembly experience of your CyberBrick models.