Roly Poly Egg  METAL LATHE MACHINE EXERCISE
 
...is a toy that rights itself when pushed over.  In order for this to happen, it needs to
have a heavier bottom hemisphere piece with a low center of mass. Different center of masses determine the time it takes for the egg to seek the upright orientation.
 
the roly poly is made up of 3 parts: the acrylic top, all thread, and steel bottom
Fabrication Process   ⇣⇣⇣⇣⇣⇣   (all taps= 5/16 - 18'')
 
The lathe is usually used to make larger items so I thought it would be a good challenge to try to make something palm size. I made a jig and had to work precisely with the excess materials.
Part 1 ARBOR (JIG)
Center piece, face off, drill and tap 
Part 2 - ACRYLIC 1'' ROD (Thank you Jane for teaching me how to maneuver the radius cutter)
Use radius cutter to form egg shape, part off smaller section, flip around to face then drill and tap end all the way through and .8'' into the egg 
PART 3 - COLD ROLED STEED 1'' ROD
Face off, drill and tap as far into the end without hitting the end
Part 4 - FINISHING STEPS
1. Finish rounding off steel by attaching it to the arbor with small enough piece of all thread, part off wanted piece and grind flat surface til smooth
2. Attach acrylic to arbor with all thread and part off the wanted part. Make sure to oil lots and not hit the all thread with the parting tool
3. Put it together! Done!
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