… three-dimensional space, to be precise.

[This is post #15 in a mini-blog-post series for NaBloPoMo 2015. Jump to the first, previous, or next post.]

Now that the scaffold is complete, let’s use it! Find your straws; today we’ll use just one of the five colors. Make sure they are already cut or creased as described in Step 1 few days ago.

To insert a straw into the scaffold: the long end of the straw enters at an arrow,

and it tracks the dotted gray line, emerging only when this line ends:

This is important: each and every straw will be inserted with this same recipe, and you don’t want them in backwards, so here are those steps again:

Insert the long straw end at an arrow, and follow the dotted line to the exit.

Let’s do the same to the other two arrows on the same hexagonal face:

Now there are four faces touching these three straws: the one whose arrows we entered with, and the three we exited from. The pink straws will touch only these four faces! So all that’s left to do is repeat with these other three. Here I’m using three more arrows on a second face (before and after):

And here’s the result with all 12 straws inserted into all 4 faces:

Tomorrow we’ll close up the corners to finish our first tetrahedron!