Did you kid/grands have one of the small microscopes they used to look at bugs, buggers, and whatnot? Find one at a yard sale and look at different sewing threads under it. You will be shocked! You can see the problems you'll have before you ever use it.

What you see is why I use King Tut for quilting and Aurofil for piecing. I hope you were talking about lose, ratty thready and fuzzies and not BUGS!
Connie

Never thought of doing that. It could be scary.

I was surprised that some of the more expensive threads looked bad, lots of slubs and thick thin spot throughout. The YLI thread was the smoothest looking of all the other brands I had on hand. Connecting Threads Essential was very even and looked pretty good.

Because I homeschooled my sons, we have a regular microscope used for high school biology. Like Bellaboo, I was surprised at the mixed results. Most of the mercerized cotton threads (including C&C) were uniform, but one of the very smoothest threads was the polyester serger thread. After all, it's plastic instead of a natural fiber. The fluffiest were the cotton-wrapped polyester. But really, I have used all of them without problem. I sew for hours at a time, so I keep a lint brush next to me and swab out the bobbin casing area every hour or so. Most of the lint comes from the fabric itself, or the batting if I am quilting.

Interesting that Connecting Threads Essentials, one of the cheapest threads on tjhe market, looks good and even as opposed to some of the more expensive brands.