I've since changed to bamboo skewers.
This was for two reasons. Bulk dowels were inconsistant. Some broke on landing and many were warped.
The bamboo skewers are very strong! They are also sharpened on one end which makes it easier to insert into the pre-drilled holes in the styrofoam ball.
Bamboo also adheres well using white and yellow wood glues.
Those tapered ends are very sharp.
I sell a lot of Sputnik kits to school groups. I don't want a young builder to hurt himself with the sharpened bamboo.
The sharp tips are taken down by sanding four at a time on some 100 grit sandpaper.
Here's a hundred or so of the skewers with the tips sanded down to a blunt end.
I'll go through the bunch and throw away any rough and warped antenna.
Any discolored sticks are also thrown out.