I learned to sew on an old Nicchi in the early 60s and often heard "leave the tension alone. The machine I have been sewing on for the last 30+ years is the New Home Combi . It served me with excellence until a small child played with the 'knobs' . The old repairman that got it straightened out said Never adjust the tension without the foot in down position. Has any one else ever heard this? Since practicing this I have been able to keep the tension right on track.