Which Singer model 15?
 

How do I figure out which model 15 it is? I need a bobbin case and there are different ones shown for different versions.

I have recently gone through the process of identifying my new model 15 Singer treadle. Had quite a time but finally figured out it is a 15-88. It is a treadle, flat side of needle faces left, and threads right to left. The bobbin case hinge opens on the right. Contact Jenny at Sew-classic.com and she will help you with bobbin case and bobbins. I was lucky, mine came with bobbin case and about ten bobbins. Don't try to use Sandman Collectibles to identify your machine. It will misidentify it as a 15-91. I am ordering a belt for mine today and in process of refinishing the cabinet. Can't wait to sew on it, tried it by hand turning the wheel and it makes a wonderfully straight, even stitch with no adjustments. Whoopee!! Good luck with yours.

So what is the difference between the 88 and the 91?

Although there are many similarities, and the needle does face flat left and threads right to left on the 15-91 as it does on the 15-88, the 15-91 is ELECTRIC. And I made a mistake in my earlier answer about identifying this machine through Sandman Collectibles. When you put all of the factors in it identifies it as a 15-96. Go to Sandman Collectibles and try to identify you machine based on your machines parts and structure. See what happens. You can pm me if you have further questions.

So if its a treadle it is a 96?

No necessarily. Here are some ways to tell the difference between 15-88 and 15-96:

15-88 has round stitch length control plate.
15-88 Bobbin case latch opens on the right. The finger is at 11 o'clock position (part #125291.)
15-88 Feed dogs drop.

15-96 has rectangular stitch length control plate.
15-96 Bobbin case latch opens on the left. The finger is at the 1 o'clock position (part #15277.)
15-96 Feed dogs do not drop.

Bobbins for both are the same #2518.

Both the 15-88 and the 15-96 have flat side of needle facing left and they thread right to left.

You can also go to The Needlebar website: They have a page for Singer Model 15 comparisons. This should help you identify your machine. Good luck to you. I am ready to order some items for mine tonight from Sew-classics.com (Jenny) and can't wait to start sewing on her.

http://needlebar.org/main/15chart/index.html and this discussion offers a little summary, too http://sewing.patternreview.com/Sewi...ns/topic/46613

It's sounding like mine is also a 15-88
Here are pictures of bobbin area and stitch length control.

The 15-88 can also be electric. The difference is whether the motor is directly attached to the upper plate on the back of the machine (15-91) or attached behind the machine with a belt drive (15-88). My mother's 15-88 (someday mine) was purchased new in 1935 as a treadle. Three months later Dad bought the Singer motor for it. Singer offered the 15-88 both with and without the electric motor, but both have the same treadle base. I have verified all this with the original manual, as well as my mother's personal story. I love Mom's/my 15-88 and know you will love yours.

Shirley that is good to know. I am almost certain that Mom-6 has a 15-88.