Takedown arrows are quite easy to make. I have been making demonstration darts for atlatls for years by taking the idea from Atlatl Bob, aka. Bob Perkins, who sells such a product.
To make a takedown arrow would entail the following steps.
1) At the archery shop have them cut an aluminum arrow blank in half
2) Glue the threaded inserts normally used for points into 3 of 4 ends.
3) Glue your nock into the 4th end.
4) Cut the head off a machine bolt, touch up the threads, I believe 8-32 is the correct thread size
5) Use lock-tite to permanently glue one end of the machine bolt into a threaded insert.
6) Fletch the arrow
7) Thread in your choice of point (target, broadhead,etc.), thread the two pieces together and you have a takedown arrow.
The reason for having the archery shop cut them is to ensure a perfectly square cut on the end by using their jigs/cutting machine. For touching up the threads I have a pair of wire strippers with a threading tool built-in to the frame.
Using a similar mechanism I have made several dozen atlatl darts that come apart for easy transport from home --> range --> schools --> scout meetings, or wherever there is a request for the local caveman to put in an appearance. It may not be authentic, but it makes a wonderful demonstration set of equipment that I don't worry about kids/adults breaking or messing up. And for a bonus they come in camo patterns.
