Hard to believe something so simple can have such a huge impact the success of one’s project, yet it’s so true. Ever had the quilt binding come loose in the washing machine? I learned the hard way and now use waxed, hand-quilting thread to hand-stitch my bindings. 
That is, unless I machine stitch the binding.
I like to use 50wt cotton thread for machine piecing. Many of my quilt guild members prefer Aurifil thread. I tried to like it, but Pfaffie pitched a hissy fit whenever I tried to use something other than Superior Threads products. Now that I have Jewel, (my Janome 6600), I can sew with just about anything. What a relief! Superior Threads products are excellent, but are a little difficult to find in my area. I have to order them online or buy at one of the big consumer sewing shows. Aurifil is more readily available (yes, it is a little pricey!).
I’ve also found that the same weight thread can vary widely in thickness. Connecting Threads offers its own brand of thread, which is a good quality “sturdy” thread that my Featherweight absolutely loves. When precision matching and scant 1/4″ seams aren’t required, I like to use this thread. I’ve also had satisfactory results using it in the top for machine quilting when paired with a “thinner” bobbin thread.
My favorite combination for piecing is to use Superior Threads’ Masterpiece/So Fine in the top and Bottom Line in the bobbin. I know they say not to use polyester thread because it’ll rip through the fabric over time, but this stuff is really soft and fine. If my longarm quilter (who has won numerous awards by the way) uses polyester thread to machine quilt, why can’t I use it myself?????? A large cone of John Flynn’s So Fine costs about the same as a medium size spool of Aurifil. And it lasts a whole lot longer, too!
In my experience, rayon and silk thread are great for applique work, but I’ve not had any luck at all using them for machine quilting.
Which thread(s) do you like best and why?
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