DRS Overview

 

I started into differential rotation speed (DRS) spinning with the simple goal of using 2 drive bands to get the flyer/bobbin assembly to spin faster – thus I did not want either drive band to slip. Physics and Alden Amos’s Big Book of Handspinning,(page 390 and seq.) told me that if there was no slip, yarn had to be wound on to the bobbin as fast as it was twisted, and it had to be twisted continuously as fast as it was wound on to the bobbin. DRS is a kind of clockwork.

This was very different from Scotch tension, Irish tension, or double drive with slip, which all have two phases; “yarn lock” and “wind on”. This two-phase process slows the spinning process down – a lot.  I have and sometimes still use Scotch tension and more commonly Irish tension flyer/bobbin assemblies.  My DRS (and accelerator) allows me to spin several times more yards per hour.  The DRS makes the accelerator worth while.  Without DRS, I cannot draft fast enough to make the accelerator worth while.

A single continuous yarn formation phase that combines twist insertion and wind-on, allows a change in the physics of the draft triangle. The yarn “self-assembles”. It is physics, but when one does it, it seems like magic. It seems as powerful as anything in Harry Potter. Suddenly, every spinner that does not use the technology seems like a “muggle”. Those muggle spinners seem to hate all of us that learned our physics and math. Those muggles call us trolls and worse.

Physics and math are learned by paying attention to what is going on. Spinning demands focus, and paying attention to what is going on. Thus, it does not surprise me that the spinners of old discovered DRS. It astonishes me that most modern spinners cannot see DRS. 

Today, with my “accelerator”, I can spin an Irish Tension flyer/bobbin assembly much faster than I can draft – my spinning speed is not limited by the speed of my flyer/bobbin assembly, but by the speed at which I can draft. With DRS and yarn self-assembly, I can spin 4-times faster. It is that yarn self-assembly that allows me to spin 560 yards 9 tpi yarn in one of Alden’s “Golden Hours” of 48- minutes.

The self-assembly of the yarn is an interaction of the rapidly rotating yarn as it is withdrawn from the drafting triangle. My experience with low crimp commercially processed wool tells me that the crimp in the wool fiber is important. However, when Stephenie Gaustad came over, and repositioned my hands so that my DRS system really worked for me, I was spinning cotton. I know my DRS system works for flax as well as any wheel in the local guild. My 2-flyer linen wheel has DRS, but it has some corrosion issues.  Crimp may be more important at the twist/grist ratios of wool.

The mechanics of the system are not new. There are drawings of similar devices in Leonardo de Vinci’s notebooks, along with sketches of treadle systems. The woodworkers and metal workers of LdV’s time, made all kinds of spinning tools and they used various treadle devices in their own tools. If needed, they would have put treadles on the spinning tools that they made.  Sewing machine treadles were not the first treadles used in industry.

You can be sure that both the silk threads and the wool threads in fabrics worn by LdV’s patrons were produced using some kind of a DRS mechanism driven by treadles.  While art uses symbols of heritage and tradition, LdV’s sketchbooks document then current technology. When you look at the sketch books, note that historical objects (from other’s old sketch books) are drawn in one perspective, current technology is drawn in another perspective, and ideas for the future are drawn in another perspective. Devices that are trade secrets are framed by a window or door.