I am shopping for a new serger. What is differential feed?
Sergers equipped with differential feed have two feed dogs, one in the front and one in the back. When the differential feed is set at N the front feed dog will feed the fabric at the same rate as the back feed dog. When the differential feed is set at 1.3 to 2 the front feed dog will feed more fabric than the back . This is because the front feed dog moves a greater distance than the back feed dog. For example, when the differential feed is set at 2, the front feed dog will move twice as far as the back feed dog. In this case, the front feed dog is feeding in twice as much fabric as the back feed dog is feeding out. The result is that the fabric will be gathered. Differential feed settings from 1.3 to 2 are used for gathering and easing as well as compensating for stretch distortion of knitted fabrics. When the differential feed is set from 0.6 to 0.8 the front feed dog moves less than the back feed dog. For example, when the differential feed is set at 0.8 the front feed dog will fee
