1) Feed Dogs are normally provided with either coarse or fine cut teeth, single row or double row, depending on the material you are sewing. Generally, the Feed Dogs should be set as low as practical to allow the work to feed. The length of feed can be changed by removing the Feed Eccentric and substituting an eccentric of shorter or longer stroke. Feed Eccentrics (6-82-#) are marked to indicate approximately the number of stitches per inch produced at the edge of the fabric.
2) The Feed Dog and Needle Plate must match each other and it may be necessary to change Feed Dogs to prevent interference with the Needle Plate when very few stitches per inch are used.
3) Machines designated by the letter D in the style marking contain a differential or gathering feed. The differential feed contains two separate Feed Dogs, with separate Feed Carriers and separate Feed Eccentrics. This separation allows the front Feed Dog to be set up to travel farther than the rear Feed Dog. This gathers the fabric and prevents it from being stretched or lengthened while it is being sewn. The difference in the throw of the two Feed Eccentrics creates the differential feed. The difference between the two can be very little or quite large depending on the number of stitches per inch you desire and on the elasticity (stretch) of the fabric.
4) On certain fabrics it may be desirable to tilt the Feed Mechanism. To make this adjustment loosen the Set Screw 48 5/32, then slowly turn the Feed Carrier Block Pin to the desired location and tighten the set screw. When the screw slot in the F.C. Block Pin is level with the base of the machine, the feed dogs will be in their standard position. It is never necessary to remove the Set Screw 48 5/32.