Sewbeadit,
Threading the bobbin case on the White Rotary takes practice. I've had mine since December 2014, it took me about 3 months to figure out the bobbin case. Join the Facebook group "Treadle Quilters". In their files is a manual and also pictures showing how to thread both the machine and bobbin case. I'm a member of that group, its been a huge help for me.
Sharon in Texas