Wow, it works!

  

  
I made a Rube Goldberg Machine, and it actually works! I've been knitting a lot lately, and given that decent yarn is terribly expensive, I took a notion to recycle the yarn out of sweaters from Goodwill. Which is all well and good, but it takes forever using a drop spindle.

Back when I did my initial experimentation, I had tried to figure out a method for using my treadle machine base to spin yarn, but my engineering was for crap and I abandoned the idea for several months. I was even seriously considering buying an actual spinning wheel to speed up plying the yarn I got out of secondhand sweaters, until I came across plans for building your own.

That's when I learned about scotch tension. See, when you spin yarn, 2 things need to happen. First, it has to get twisted. Second, the twisted yarn has to get wound up onto a spool or something. With the most basic type of spinning mechanisms, you spend a couple seconds twisting, than stop twisting while you wind up the string you just made. Scotch tension is a method for getting these 2 things to happen simultaneously!

As you can see, the gadget above has a spool (bobbin, in the parlance) mounted between 2 arms. The thing with the arms is the flyer. The flyer has a little wheel stuck on it, and the belt from the treadle table goes over the wheel and turns the flyer. This is what twists the yarn.

Well,  if the bobbin is sitting on the flyer, that means the bobbin is turning at the same speed as the flyer, and if all the flyer does is twist the yarn, how do you get the yarn wound up?

It is ridiculously easy: all you do is loop a little piece of string over the end of the bobbin, causing a teensy bit of drag. The bobbin will then turn just a little slower than the flyer, so that not only does the flyer twist the yarn, it rotates around the bobbin, thus winding and twisting at the same time.

The first time I read about how that works I thought well dang, that is just brilliant. I'd been looking at plans for spinning wheels that work using complex arrangements of drive belts and wheels with multiple grooves in different diameters calculated to cause various ratios of twist and take up, and it was all just too daunting. Scotch tension is so perfectly low-tech it's foolproof. Want your yarn less twisty? Tighten the string. Want your yarn to be more twisty? Loosen it. Want to make yarn faster? Pedal faster, silly!

Edit! Featured Instructable! Squeeee!!!!