Bobbin Case History of the Singer Featherweight 221 and 222

Many bobbin cases look alike, but there are a few differences worth noting.  There were a total of five different stamping sequences used to mark the Singer Featherweight bobbin cases.  The number (45750) was consistent through the years, but the order and location of the stamp varied.  

Let's begin with the Bobbin Cases made in the USA.

The first stamp was used from the beginning of Featherweight production through the very early 1950s. 

The stamp read:

Simanco USA
45750

1933-1950 Approx.

The next stamp was used for just a few years and was marked:

45750
Simanco USA

Approx. 1950-1954

The last US bobbin case was stamped similar in order to the first one, but the lettering was far lower on the bobbin case.

Simanco USA
45750

Approx. 1954-1957

In the UK there were two bobbin cases; both of which were stamped, "Simanco 45750."  

The first case had its number on the outside, and it was stamped upside down.

Simanco
45750

UK 221K and 222K from 1947-1954 Approx.

The final UK bobbin case was stamped on the inside.  The case was used on all later Featherweights in the UK including the white 221s.  

Simanco
45750

1954-1969 Approx

 While each bobbin case had its own era, all original Featherweight bobbin cases are interchangeable.  If the bobbin case in your machine happens to be from a different era than the machine itself, no worries; it is better to have a vintage original bobbin case than a replica any day!  After all, proper stitch formation is of most importance.  

That said, is your machine having trouble with stitch formation?  It could be that your Featherweight has a replica bobbin case as opposed to a vintage original bobbin case.  Here is a link to our tutorial on troubleshooting stitch problems.