MATERIAL NOT FEEDING CORRECTLY :--1.Stitch regulator set too close to ' o ' point .

2 .Dirt under needle plate near feed dog .

3 .Incorrect presser foot pressure .

4 .bent presser foot .

MACHINE RUNS HEAVILY :----

1.Lack of oil .

2.Thread wound round wheel or treadle bearings.

3.Belt too tight

4.Bobbin winder pressed down .

5 .Thread jammed in shuttle race .

6 .Gummed oil or dirt on bearings .