Sewing with Sunbrella fabric
I'm locking the barn door after the horse has escaped, don't know why I didn't think to ask this question before I started my project...I've just finished sewing all of my patio cushions out of Sunbrella fabric (Buttercup yellow).
Q#1...Why is it that the top stitches are as loose as if they were a basting stitch, even with a normal stitch length of 2.5 and not a 6.0 basting stitch? The stitches aren't raised, yet I can pull it out much easier than if it were sewn on cotton fabric. It doesn't look right either, especially compared to the reverse side where the bobbin stitch does look normal, nice and tight. I've tried an 80 and a 90 needle, changing fabric weight setting from medium to heavy, tightening tension to no effect. What is it about Sunbrella fabric that makes it do this? I've compensated for this by stitching over twice to help lock in the stitches. I'm using 100% polyester thread. Doesn't seem to be a problem with the machine because it stitches normal when I go back to cotton fabric to test.
Q#2...since this is light colored fabric should I spray Scotchgard on it or is that not necessary with Sunbrella? I know it is water resistant already but could a spray help to keep spills from staining the fabric?