For some projects, I set out to make something very period, buy the best materials I can get my hands on and away I go with it. Other projects, however, do not have as much pre-planning or time to collect the appropriate resources. I am using a piece of my weaving (using my hand-spun weft) as an A&S entry soon and needed to hem the edges. I have no linen or wool thread in neutral colors (nor any uncolored) and most of the colored thread is actually part of other projects, so I could not justify it for this even if I didn't mind, for example, bright red thread.
Unfortunately, the idea of using regular Gutermann also made me twitch.
I came up with a solution that I like well enough now to later expand upon! I made my own handsewing thread.
Sewing thread, however, is not single ply, rather it is a strong plied yarn that can hold up much wear. My solution for this, was to make my own thread. I took the 12/1 (the thinner of the two) and plied it more tightly (Z spun, as is the original direction of the yarn's twist) with my spinning wheel onto two bobbins. I then plied those with the wheel in the opposite (S) direction. I used a small plastic hank from some camping rope to wind and block it by submerging in hot water and allowing it to dry.
The result is unevenly spun (I was varying my amount of twist as I went so that I could determine how much to use in the future) but the result is still a nice, strong thread for heavy sewing.
I actually am considering ordering the 20/1 Vaxbo linen yarn and making a more fine thread for general purposes. I also am not confident that the very fine weft in my current weaving project will ply nicely into a thread that I can use to sew the final garment.