Hope you find an organizational system to manage these - one thought, of course I have two machines that use the same plastic bobbin and one that uses the metal, so I don't have the problem. But, I do have embroidery bobbin thread on some and normal thread on others. To distinguish, all embroidery bobbins have a black dot on them. Maybe you can color code them by machine. The other thing I got rid of was having so many bobbins filled with thread I may never use again, or anytime soon. Some one on this board, many moons ago, mentioned using up the bobbins, using them as the thread and the bobbin when piecing. So I have done that and it has become a very manageable thing in my sewing room.