My favorite double drive wheel is the CPW (Bordua) where I adjust the tension by "whacking the maidens" while spinning and don't lose any time or momentum. That said, I have quite a collection of wheels and the real difference that I find in the various tensioning methods is actually in the yarn. For medium to fine yarns that need a firm twist - double drive is lovely as it twists right up until the yarn winds on. For lofty knitting yarn that will be plied, the Scotch tension is my preferred wheel. The Irish (think Louet) tension pulls so quickly that it is very easy to produce softly spun yarns - even at large diameters. And that is only talking in terms of "sweet spots" - an experienced spinner can draft the fiber in nuanced ways to influence how the wheel is handling things. The endless discussions about slippage, measuring twists per inch, whether the wheel keeps turning when you stop, starting without using a finger to start the wheel, double or single treadle are all secondary to the yarn being produced. Yes, in a spinning mill, the tpi must be set prior to the spinning process for consistency - they are also using predrafted fiber that is practically the right diameter for the intended yarn. In a mill setting everything needs to be in proper adjustment or the machinery will produce garbage yarn far more quickly than with a hand spinning wheel. Applying industrial thinking to a spinning wheel in your living room isn't so clear cut. When a spinner drafts fiber by hand, there is NOT a consistent amount of fiber going to the bobbin from a machine. The hardest part of spinning consistent yarn is less with the wheel but with the spinner. Once you have developed a smooth method of drawing out fiber into the diameter of yarn desired with the "right" feel - you "just do it". Believe it or not, you can actually feel how much twist is in that yarn and when to let it in without firm counting methodology - but only with considerable practice and experience. Funny is that the relationship between producing yarn on a spinning wheel and the control of the process with a simple treadle mechanism and simple drive band with slippage seems to be a healthy one. When there is little or no slippage and constant speed - as with most modern electric spinners - seasoned spinners often complain because they cannot instinctively coordinate hands and feet to adjust for, say, a clump of fiber that doesn't draft as well as the rest of the batt or roving. (I realize that especially for anyone with a disability, the e-spinner is a great tool). And just FYI - over the years Ii have tried and even owned wheels made by the latest "popular" wheel makers, the "special" ones, and quite frankly they all spin, most spin well, but there is some point where the prices exceed the perceived advantage of such wheels. My current collection are all "factory" wheels by companies that procuce(d) many wheels - like the old Beetles, they don't carry that Porsche image but they do get you where you want to go.
Sara von Tresckow, Fond du Lac, WI sa...@powercom.net http://www.woolgatherers.com Dutch Master Loom/Spinning Chairs/Öxabäck Looms, vendors at Wisconsin Spin In
