Service - How Often
If you are a sewing machine user, the last thing you want is to start a project and find your machine is not working properly. Most of these situations are avoidable with a little care.
For every few hours sewing, you need to clean out the bobbin area and place one drop of sewing machine oil on the race (the track) on which the hook moves. It is also a good idea to change needles frequently. Using quality thread and fabric will also prevent problems. All of this should be done by the user. But there is more.
Sewing machines are machines. They require cleaning, lubrication, and adjustment. Did you know that the oil in you machine deteriorates over time. Within six months, it begins losing its viscosity (oiliness), becomes sticky, and eventually hardens. Unlike your car, the oil is exposed to dust, dirt, lint, heat, cold, moisture, everything in the air. Unless these old lubricants are removed, the machine will eventually fail.
For this reason, the average user must have their machine professionally serviced annually to maintain it. Heavy users need more frequent service. The occasional user should always have their machine serviced before starting a new project even if it has been in a closet.