I just got a Singer 15-87 with the RAF decals, and have started cleaning it up. When I removed the bobbin case, I had a problem with the latch lever opening too far, which then allowed the latch lever to simply slide completely off the case. It appears that the mechanism to hold the lever in place was just the head of a very small screw sticking up, which obviously didn't do it's job very well.

In the process of all of this, I noticed that the bobbin case (the 1 o'clock variety) did not have the SIMANCO name stamped on it anywhere, just the letters "JHI". The bobbin case on my 15-91 does have the name and part# (125291) stamped inside its case.

Being new to vintage machines as a hobby, and noticing the name stamped on virtually every part I come across, big or small, I'm wondering if the absence of SIMANCO on the bobbin case is an indication it is an aftermarket part.

I'm also wondering if problems are common with replica cases. Original bobbin cases that are not already attached to sewing machines seem to be a very rare commodity.