A few rotary bobbins and bobbin cases
Bobbins
The White Rotary, Kenmore 117 series Rotary, and Domestic Rotary machines, all made by the White Sewing Machine Company, use the White Rotary Bobbin – Part# 744.
The Kenmore 120 Series Rotaries (Manufactured by New Process Gear), Free-Westinghouse Type E (Manufactured by Free Sewing Machine Company), and New-Home Type F (Manufactured by Free Sewing Machine Company) all use a smaller rotary bobbin that I believe to be part number “10025”. This smaller bobbin can be substituted with bobbins used in the Singer 221, 221, and 301 sewing machine.
Just as a reference, above are the two most common bobbins you will find, the Singer class 15 and class 66 bobbins flanking a White Rotary bobbin.
Bobbin Case
Over the years the White and Domestic Rotaries used two different bobbin cases, while the Kenmore 117 series Rotary hook sewing machines used only the older style of the two bobbin cases.
The older style bobbin case is often referred to as the “Wishbone” style bobbin case, and the later bobbin case is often called the “New Style” bobbin case. In more technical terms, the Wishbone bobbin case is part number “836”, and the New Style case is part number “69727”. Obviously these two bobbin cases are not interchangeable.
The bobbin case for the Free-Westinghouse Type E, and New-Home Type F use a smaller Wishbone style bobbin case, part number “3368”. Please note that I’m not 100% sure this is the correct part number, but that’s what I’ve found so far.
Note: It’s quite possible that you have a sewing machine that has a rotary hook, and it may have even been manufactured by the White Sewing Machine Company, but does not use any of these bobbins or bobbin cases.
