I have stuck with one thread (Aurifil 50 wt), both top and bobbin, and am ready to expand my horizons! Can different weights of thread be used for the top and bobbin? I'm pretty sure the answer is yes - but are there certain guidelines I should be aware of when experimenting?
Also, while I am not showcasing my quilting at this point (I tend to either stipple or other simple meandering stitches), I don't want it to be invisible either. I would like to try polyester (perhaps something like So Fine). I tend to like solid colors, so that rules out So Fine #40 from what I see. Would So Fine #50 disappear into my quilt?