I have made a chart of all my sewing machines from date of first acquisition down to latest. The info is as follows:
Make, Model, Serial No., Age, $ paid, Place acquired, Date acquired, Manual (yes or no), Needle position (F/L, F/B, F/R), Needle size, Thread (R/L, F/B, L/R), Bobbin (up or down), Bulb (push or screw), Belt (yes or no). I keep one copy in dining room with five machines, and one downstairs in sewing room with six machines. It has saved me so much time because I don't have to pull out a manual every time I can't remember something about each machine. Nearing 72 years of age, this happens quite often, especially if I have not used one of them lately.