I have two 301s (a black one and a beige one) and I love the way they sew. When I got my first 301, it sewed but was bunching up the fabric and stitched really tight. I thought it was the tension but after downloading an adjuster's manual I found that part of the gib (I think that is what it is called) was broken off. I ordered a replacement from Glenn Williams, replaced it, adjusted the tension and then it sewed great. Look at J Miller's photos. The gib is the curved piece with the number and screw on it. The very tip of mine was gone. I don't know if that is your problem but worth checking. Don't give up. You will love the 301.