Chalkboard sphere

This instructable will show you how to build a blackboard sphere to write on. Because sometimes a flat area is not enought!

Step 1: Assemble the polysyrene sphere

You have to glue the two pieces together. Pay attention to use a glue intended for polystyrene (some glues can dissolve/liquify it)

Comments

[freakyqwerty]

Using glue to dissolve polystyrene is a way to make simple once-use molds, you simply carve the polystyrene use it as a mold when the model is set use the glue or even better ethyl acetate to dissove the polystyrene to release the model.

[electfire]

You can also use plain old acetone (sold in most box stores and hardware store to cleaning) - this is also a cool way to "melt" (Doesn't technically melt it) Styrofoam... you can then use the liquified plastic to make things with...

[derte84]

Will it solidify later?

[electfire]

-oops! I forgot to add that in - Once the acetone is removed (usually just let it evaporate) It will solidify.... I wish I had heard of this method before I tried to melt Styrofoam over and open flame (a lighter)... not only did the Styrofoam not melt but in caught on fire and Styrofoam burns in an irregular way - the flame will worm it's way through the foam, all the while creating a nasty smelling smoke, which I am sure shouldn't be breathed in.

[freakyqwerty]

What were you trying to melt styrofoam for? Also I'm pretty sure most types of smoke is bad to breath in...

[derte84]

for casting maybe..

[electfire]

I was trying to melt Styrofoam to make it into usable plastic... as for smoke inhalation - some types of smoke smell good... like wood smoke, incense etc...

[freakyqwerty]

Yeah I like the smell of wood...

[derte84]

0_0 ... I'll try definitely with acetone

[derte84]

Worth a try!

[zazenergy]

this is a really fun project! what do you find yourself using this for?

[derte84]

conceptual maps :)