I'd like to say hi to everyone, long time lurker, first time poster. I've sewn fabric and worked with leather since I was little and I'm in no way a pro.
I'm starting to accumulate quite a few spools of industrial thread bonded nylon/ bonded poly #69- #207 and I have a few different brands to personally access what I like. One thing that I have noticed is that one brand of #69 looks almost identical to another brands #92. I can feel a slight difference when I break the thread although this method lacks any accuracy. I could thread it through a needle and gauge how it slides. Visually they are they are pretty much indistinguishable.
Is there a good way to identify unknown thread? Is there a good way to permanently mark the cones for easy identification because the stickers are terrible?