I use story sticks when doing renovations or fitting trim or when building a 'one off' project, usually from available wood. If I am making a serious project I use purpose acquired materials and even a plan. (sometimes) For me it is just easier to copy a measurement with a story stick than take a measurement with a tape.
After checking out a number of commercial sticks I decided to make a set for myself. A while ago I bought a bundle of 18 inch graphite dowels 3/8 inch in diameter. I had no idea what they were for and really had no plan but couldn't pass them up at the cheap cheap price.
I could have made my stick using wooden dowel but since I had the graphite stick that is what I used.
The end was really easy to shape in my belt sander.
The centre section has two bolts that provide friction to keep the rods from sliding in or out once set.
If these sticks prove to be too short, too often I will be easy to add and another wooden section and make them three dowels long. I'll jump off that bridge when I come to it.