The stitch length lever was introduced around 1930 on model 15, or just before, around the same time model 201 was introduced. They were given the same stitch length lever and plate. On the older models like 15 and 99 you develop a feel for the stitch length setting, it's a minor issue when you get to know the machine better, and there's usually a bit of test sewing involved before starting to sew. The older type model 15 with out reverse were made up until 1950 at least, not too long ago a lady in the UK told me hers was made in 1950 and had the old type nut and bolt type stitch length setting with out reverse. Maybe it was particular to the Kilbowie factory in Scotland, I'm not sure.
Last edited by Mickey2; 08-14-2018 at 03:09 PM.