I am currently working on canvas slipcovers for furniture using10 oz painter's dropcloths for the fabric. I am using 70W nylon upholstery thread and sewing on my 201-2. The only problem I have encountered is the super springiness/stiffness of the thread wanting to uncoil from the spool and the bobbin if not under some tension. I am using a size 16 Organ universal needle and my machine is not laboring at all and making normal stitches, even through 6-8 layers of heavy fabric (piping plus zippers plus basic parts). I did have to really crank up the upper tension to make it sew correctly though, as the setting I use with 40-50W thread left loops on the bottom. I also sewed through a leather dog harness a couple of days ago (repair for a friend) with no problem (that one I went quite slowly with)
This is the heavy thread I am using:
[h=1]Tex 70 150 yds Xtra Strong Nylon Upholstery S964 Thread[/h]
Coats Xtra Strong Nylon Upholstery Thread for machine and hand sewing. Great for Upholstery, outdoor, and heavy weight fabrics. This Bonded 3-Ply Nylon Thread is weather and UV resistant. For best results use a size 18 needle and increase stitch length. Tex 70, 150 yds. Please note: actual color may vary from picture due to computer setting. Use chart as a reference.
