The walking foot for your 301 is not helping much. There are no walking feet made that fit the 301's feed dogs. Look at the walking foot and compare it to your feed dogs and you will see they don't match up. Many people quilt with it by simply reducing the pressure. Similarly, if you don't have a straight stitch walking foot for your 201 and 15, the walking foot teeth are not meeting up with the feed dogs and aren't helping much. The correct tools for the job help immensely. Sew Classic carries the straight stitch walking foot for the 15 and 201.
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