What should I do to maintain my Singer 1120 sewing machine?

Always unplug the machine before cleaning. Remove the needle plate and clean out lint or dust from the bobbin area with a brush, then wipe the exterior with a soft, dry cloth—do not use harsh chemicals. The Singer 1120 is designed to require minimal lubrication; over-oiling can attract dust and lint, so avoid excessive oiling. (Page 1 — Maintenance)