The excellent online Singer identification guide from Sandman Collectibles is the current gold standard for identifying vintage Singer machines.
It asks you to check off a list of features seen on your machine, narrowing it down until you arrive at the model number.
Some fabrics especially light weight fabrics may require a stabilizer.
Some projects may require the conventional two piece wood hoop.
Set your machine for normal free-motion sewing according to your operators manual.
Note: For free-arm models works best with your sewing machine extension plate attached.
Case in point--the other day I clicked on a Craigslist ad saying only "Singer sewing machine" and saw this photo: The photo's small, dark, shot from a weird angle and shows no detail, but I immediately knew it was a model 99.
These are the models I find to be most common in my area (NYC).First I'm going to start with the model 15 because that has the most distinctive "lines," if you know where to look.When trying to identify a Singer from a crappy photo, the first thing I do is rule out whether it is or isn't a model 15.The third family machine "New Family" was manufactured form 1865-1883.In 1883 the "Improved Family" machine appeared and in 1885 the VS1 (Viberating Shuttle), in 1886 the 27 / 28 and in 1912 through the 1950's 128 / 128 were manufactured and sold.