I hope someone can help me. I recently bought a Brother CS 6000 machine. The first thread I tried using was a 100% Glased Cotton Quilting thread. I could never get the stitches looking right. I tried to adjusted the tension but it didn't work. I thought it might be because it was a cheap glased cotton. I bought some good Coats & Clark cotton machine quilting thread but I got the same results. I figured that I could always use this thread for hand quilting. Then, I put on some old thread that I've had for years and that worked perfectly. I didn't need to adjust anything. What is the best thread to use for machine quilting?