Solenoid Mini Engine | Four-Cylinder Electric

It runs at a good speed at 7V 2A.

Parts Needed:

• 5mm steel rod (≥110mm long) https://a.co/d/i9PcLPT
• Copper wire 0.5mm (~80g needed for each coil) https://a.co/d/8sGAtHW
• (2) 16x5x5mm bearings https://a.co/d/6BE9lIB
• (28) Cylindrical magnets (28x 10x3mm https://a.co/d/1pj4dlN) 
• (2) Limit Switches https://a.co/d/0hFRVpu
• M3 Bolts and Nuts
• (1) capacitor at least 25v and high capacitance https://a.co/d/7JtPDyL
• (2) Diodes at least 25v 5A rating https://a.co/d/hw464Bk

1. Cut the 110mm steel rod into 2 30mm, 2 15mm, and 1 20mm sections then glue together with the ShaftConnectors to make the shaft.
2. Push 7 magnets into each piston (don't fill the whole piston with magnets there should be extra room)
3. Attach the PistonConnectHooks to the pistons with M3x10mm Bolts.
4. Attach the other side of the hooks to the shaft.
5. Push bearings into the front+back sides. 
6. Glue the coil caps onto the CoilBody parts.
7. Wrap wire around the coils ~80g each coil.
8. Glue the CoilBodies into the left and right sides.
9. Put the shaft through the bearings, the pistons in the CoilBodies, and put the sides together with M3 bolts.
10. Put the bottom on with M3 bolts.
11. Wrap something heavy like copper wire around the flywheel then glue the cover on. (may work without wire inside or use different flywheel)
12. Put the Flywheel and Ignitionwheel on the shaft (don't glue the Ignitionwheel down yet) may need to add spacers.
13. Put the switches on the side with holes attatch with M3 bolts.
14. Wire the switches, capcitors, diodes and coils together. (see circuit diagram)
15. Make sure the ignitionwheel is turned so it activates the coils when they are ready to be pulled in.