Radial Engine Fidget Toy/Spinner

I've designed this fidget toy/spinner (It doesn't go fast like a regular fidget spinner, but it's still satisfying to watch all 5 pistons go up and down when you spin it).

I highly reccomend using my print profile as it's optimized for the countless fails that could come with these parts. These settings almost guarantee success on all parts. To fit 5 pistons in such a small fidget spinner the tolerances are pretty tight, so it's worth spending the extra time on a 0.08 mm layer height (4 hours for all components).

This is a little more complicated to build than my previous 1 cylinder or V2 fidget toys and therefore I've made an assembly guide the best that I can. If you want it to run smoother you can use the bambu lubrication oil on both ends of the connecting rods, in the hole of the crankshaft/counterweight and also in the hole of the crankhouse.

Start by cutting 5 pieces of 1.75 mm filament to a length of 7mm (0.27 inches). Now take the parts shown on the following picture and assemble them as shown:

Now assemble the 5 pistons using each of their piston pins (The ones printed with a brim on my print profile) and connecting rods as shown on the following picture:

Now lay the 5 piston assemblies on the previous assembly as shown and assemble the other part of the crankshaft as shown:

Insert the assembly into the Crankhouse (Before doing this please turn the other crankshaft a few rotations on both parts of the housing to free up the tolerance and make it run smoothly. This is also a great time to lubricate if you want):

Now put on the top part of the housing and put on the 5 rings untill they meet resistance (They only go on one way so if it doesn't fit try turning it around):

Now find the ring that is a little bigger than the 5 rings you've just put on. Use this ring as a tool to push the rings fully onto housing until you hear a small click (Push straight down on a table like shown on the picture):

Now put on a knob on each side and it's ready to go: