Originally Posted by
Neesie
If the dowels are just a little too big for your bobbins, just take a piece of sandpaper and sand/polish the dowels, until the bobbins will fit onto them. If you put the spools beneath the bobbins, you'll only have to sand/polish the tops of the dowels.
This was going to be my suggestion as well. Or possibly could your DH mechanically taper the dowels for you so it wouldn't be quite such a tedious sanding adventure?