by manuelgarcia, published
This is a working BB8 model whose internal mechanism is very similar to Sphero.
It is 96 mm wide and its easyer to asemble and faster to print than the previous one, as it is about a third part of "Version 1" and you can open and close the sphere without removing any screw.
I will complete the existing instructions soon.
Supports: No
Resolution: 0.2 mm
Infill: 25-30%
Notes:
Supports are required only in Ball_a. I strongly recommend to print it in abs.
a)3d printed parts:
Just print each one once or twice if the name of the file ends in (x2)
b)Non 3d printed parts:
2 standard flat side dc motors.
4x68 mm brass shaft (you can 3d print one)
2x10 mm wood screws.
Some magnets.
Super glue (or similar)
Acetone (If working with abs)
Silicone (Any kind)
Soap (Used to work with silicone)
An arduino nano, a L293D motor driver, a bluetooth module...
c)Asembly:
-The sphere:
Take one of this.(Ball_a)
Remove supports.
Disolve them in acetone, we will use that later.
Sand the inner side.
Brush it with the acetone +abs mix.
Glue that two pieces.
Sand the excess of material.
Brush all with acetone + abs.
Do the same on the inner side and repeat all the previous steps with the other halve of the sphere.
-The driving wheels:
Print that piece, brush the internals with acetone for better results, let it dry, then, brush some soap with water inside.
Fill the mould with silicone.
Flat the silicone with your finger and some soap.
Let it dry overnight and remove the tyres.
Glue them to the inner piece of the wheel.
-Internals:
Parts needed.
Glue the two motors in place.
Glue the small gears to the motor shafts.
Cut the brass rod, put it into the frame and then put the big gears on both sides.
Glue the driving wheels to the big gears.
Glue that stopper in place.
Screw that piece on the upper side of the frame.
Take one of this and put those shafts in place.
Place that wheels on there.
Place the other part over there.
Screw that to the main frame.
