Simple Boxer Engine

Fully printable boxer engine. Use 1.75mm filament as a piston pins, it should be friction fit on the piston and lose on the connection rods.

I have modeled a little lip to the crank pin what you can melt to be a little wider so it locks the rods in place. Just don't melt the parts together!! In my case, it was not needed because they stay in place well enough.

For example, heat the tip of a flathead screwdriver and use that to widen the lip, high enough temp that it makes the plastic malleable but not melt it so you don't fuse the parts together.

Put the thumbknob through the center hole in the block and attach the crank to it after that. Like the second picture shows. In my case, it was perfect friction fit after a little bit of sanding the hole of the crank so no glue needed, but you may need some glue. Thumbknob should spin freely on the hole in the block so make sure that the glue stays between thumbknobs axle and the hole of the crank.

I can do a video about assembling