Our material is MDF and PVC flexible,  for the other 2 excises we used MDF only, so this time we wanted to do something different.

We started from thinking what is the biggest difference between these two material.  Well, one is hard, and the other is soft, and can be bent.

So we decided to use this property, and tried to form a sphere.

What we did is cutting a sheet, and then it could be stretched, then became a semi-sphere.

Then we used the joints we printed to connect 2 semi-sphere.

To provide the force to maintain the shape, we made a another bigger joint to hold a stick in the middle.

We used MDF sheet 4mm. thickness to make a sphere which is self-structure by the connecting of outer rings (vertical) to inner rings (horizontal).

For us. less is more. One single vertical ring can make other ones together, so we don’t need another ring.

For inner rings, MDF sheet was lasered cut into each pieces in different radius but for the outer ring, we have divided it precisely and laser cut it to connect with inner rings.

To make the over structure be more rigid, we need to laser cut the joint between end point of each outer ring in the locking shape by itself

Finally, we connected all pieces together then we got the minimal clean sphere diameter 12 cm. which is  the hollow core without any supporting element.

Luban ball is a kind of traditional Chinese toy, a kind of 3D puzzle. It is made of 6 pieces, and together they locked inside.

The diameter of ur ball is 120 mm,  much bigger than normal Luban balls, but this size is maybe better for milling, for the milling machine is not good at small scaled details. The material is 19 mm MDF.

Click here to watch the video → BALL~1