Pictured above is a Solidworks design of the playfield and supporting assembly. The playfield is purely custom, but the shot lines (such as the curve of the back looping shot) were designed based on real pinball machines to ensure smooth play. One difficulty here is that, due to their complexity, the actual pinball parts (e.g. the bumpers and the drop targets) were not modeled, but care still has to be taken to ensure that everything will fit underneath the playfield - the parts are much larger underneath than above.
The files are included in the repository, so feel free to adjust the design to suit your fancy.
A few highlights of the design:
The playfield is 42” by 20.25” inches, exactly the size of 1980’s Bally-style games. It is made of ½” plywood, which is standard and should not be changed as the pinball part assemblies are designed for this thickness. The walls here consist of a ½” layer on top of a ¼” layer. In the first prototype, only ½” walls were included, but these proved to be too short and could pop the pinball into the air on particularly firm shots. Secondly, this design allows for slightly raised shooter line (pictured above) which allows the ball to drop slightly into the playfield, but not fall back in.
The ramp is designed with clear acrylic and 3d-printed supports. It crosses the playfield so that it gives the player the opportunity to hit the ramp multiple times in a row from the left flipper. As such, clear acrylic is used to not obstruct the player’s view of the table:
Finally, the playfield is supported by short walls at the four corners, which keep the playfield at the standard 6.5 degrees of slope. The back wall has a bottom “shelf” that can be removed and is used to mount the electronics. This results in a game with a full-size playfield, but is much more compact than a typical game and can be carried by hand by one person. Since the playfield is a standard size, however, these supports can be removed if you want to place the playfield into a standard pinball cabinet. To do so, you may want to consider adding a ball return assembly, which is not included in this design.