Take a look at my last model :

https://makerworld.com/en/models/204867#profileId-225049

Hi everyone . I present to you the first fully functional and 3D printed Pinball. The Operation is essential. It is designed to collect the balls and with a conveyor keep track of the points scored.

Optionally it is possible to print the Launcher balls as well as the balls themselves. The balls are 9 millimeters in size. 8 mm steel balls can also be used.

For those who want to print the model with another slicer there are some clarifications to make. 

This is the preview of the project in full:

If you want to print it with another slicing software, take these things into account. First of all on the rear piece, the conveyor, you need to set adaptive layers so that the thread Is be as precise as possible:

For the optional piece, the Launcher balls, use the manual supports function where indicated in the photo and select only external brim for greater safety:

As for the buttons and feet, use 100 percent filling, this way there is no risk of them breaking during assembly and use external brim for the feet:

Even the balls can be printed. I recommend 100 percent fill and apply brim. Since they are not perfect, once you have finished printing I suggest scratching them .

HAPPY PRINTING !