Singer Slant-O-Matic Sowing machine
Mum had a junior single thread sowing machine when I was a small boy, she had made dresses with it. Later in the 1960s she bought an Electric Singer Sowing machine which had the same foot controller as this 401. You help it start gently by rotating the drive wheel with your hand whilst pressing the foot speed control.
The foot speed controller is not like a drill speed controller the motor does slow when the machine is working harder, that is there is some feel fed back to the operator. After the required oiling, the Slant-o-matic is in perfect order, much as you would expect of any Singer sowing machine of any age in 2024. It should be oiled with barbers cutter oil, this is the same very thin as Singer oil and veteran Bicycles use. Don't use 3-in-one it leaves a black residue which becomes a problem after a few decades, cyclist find. If you don't have the correct oil, thin mineral engine oil is a better option than using 3-in-one (that oil has some harm to many veteran bikes)
Although the motor should not be lubricated normally but now after 55 years greasing the bearings is due. Also checking and cleaning the brushes and the commutator.
I think mum purchased it in 1970. It was the best of the last Singer Sowing machines, that could be treadle foot driven or electric motor driven. No electronics, but has clever mechanical computing and 6 programme wheels for various features. There are a number of sowing attachments such as buttonholes, zigzag, pattern stitching, one two or three threads with one or two needles.
User Manual for the Slant-o-matic, The greatest sowing machine ever made - model 401 96 pages
https://amandawynn.com/2016/01/31/sewing-machines-slantomatic-401/