First introduced in 1935 and continued in production up until 1962 Despite the differing body shapes and apart from it's smoothness, the 201K can be recognised by the large disc with the stitch length lever protruding from it.The tension unit was directly in front on the needle which in turn threaded from right to left.
This machine has the "Acanthus Leaves" decal set which was used by Singer on the 12K and 13K models.Actually, there are lots of variables to estimating the worth of an old sewing machine, so let's look at the most important; the make/model and date, the condition, and any extras that may be included with the machine.the long bobbin/shuttle was inserted into its case which looked like a bullet, then the case was located into the machine and lay in a frame that looked like a boat hull.When the machine was running it most likely was quite noisy because the shuttle moved forward and backwards at great speed, at times it made the machine vibrate.Its bobbin had to be inserted into a bobbin case, then the case was inserted into the machine vertically to the left of the needle.
When threading the needle it had to be threaded from left to right.
It was manufactured between 1907 to 1920 the early machines were only Black and Gold with no colour.
The 66K has a bed size of 14-1/2" so is much wider than the 99K The Singer 28K had what was called a vibrating shuttle or boat shuttle or bullet shuttle...
How to Identify an old machine without a serial number..?
If your sewing machine does not have a model number, but has a serial number similar in location to the image above, use the images below to help identify the sewing machine model number.
The Singer 99k sewing machine is small in size measuring only 12-1/2" wide, this image shows an early version the 99K (99K21 - 26) made between 1924 to 1954. The stitch length was adjusted via a screw and the machine did not stitch backwards.