All the wheel makers indicate the "ratio" of their wheels in various configurations. However, because of drive belt slip, it is not a very useful indicator of anything. In fact, I did not really begin to understand my wheel until I got my digital tachometer that told me how fast my flyers and bobbins were really spinning.
Higher ratios should indicate that more twist is being inserted to into the yarn. IN THEORY, for any wheel, the diameter of the drive wheel is fixed, so smaller whorls should mean more twist is being inserted?!?!?! NO! Smaller whorls mean there is more slippage. When you get down to the tiny whorls of "lace flyers", a lot more slippage! My tachometer told me that my fancy lace kit did not spin any faster or insert any more twist than my standard bobbin, and the double drive kit inserted more twist than the lace flier, but when I tried to speed up the double drive, by making smaller whorls, speed actually went DOWN, DOWN, DOWN. Deep thought indicated that there are good physical reasons for this related to vibration waves in the drive belt so smaller whorls have much less contact with the drive belt and much more slippage. This is an effect that dominates lace flyers in modern spinning wheel making.
You get a big wheel with fancy lace flyers, and lace production is -- disappointing. First, they are Scotch Tension, -- the drag of the tension system must be overcome before you can spin anything. And, that fine lace yarn that you want to spin must absorb enough twist to become strong enough to overcome the drag of the Scotch Tension, and that is a huge hurdle. I often spin yarns that are so fine (grist greater than 30,000 ypp) that they need more than 15 tpi to have any strength. Certainly some twist can be stored in the leader, and that can be transferred to the proto-yarn before the proto-yarn must overcome the drag of the tension system, so the proto-yarn can maintain yarn lock and receive twist from the spinning bobbin. I took my tachometer around, and most modern wheels with Scotch Tension insert twist at much less than 1,000 rpm. I can do much better with a drop spindle, and I am not even very good with a drop spindle.
Modern DD wheels are a bit better in terms of delivering twist to the proto-yarn, but are desperately tricky to adjust the drive belt tension so the bobbin spins faster than the flyer, but drag on the whorls does not slow the whole system to a crawl. However, a lot of things can go wrong in a DD system that will slow the system way down: too much drive belt tension, too little drive belt tension, wear on the drive belts, wear on the whorls, lack of drive belt dressing, drive belt dressing accumulating on the whorls, are all things to monitor every few hours of spinning. DD systems have rightfully earned a reputation of being high maintenance. Which is not to say that I did not LOVE my DD, when I got it.
The obvious solution is to design a clockwork system so the bobbin spins fast to insert twist, and the flyer spins slower to wind the yarn onto the bobbin, and to wind yarn onto the bobbin no faster than twist is inserted. Such a system was invented in Florence, Italy in the 13th century for use in the silk production industry. It was the size of a room, and required a man and a boy to operate. A century later it had been reduced in size so one person would use it for spinning worsted, and it remained one of the most valuable trade secrets in the world.
In essence, a DRS wheel is a double drive spinning wheel set up as a clockwork mechanism with the bobbin whorl just enough smaller than the flyer whorl, that the bobbin spins fast enough to insert twist as the flyer winds yarn on to the bobbin at the proper rate so each segment of the yarn has the correct twist. This concept has THREE important advantages. 1) It relieves the spinner from having to control twist, so all spinner needs to do is draft to the correct grist. 2) It reduces drag and slippage in the spinning system, so much less labor is required to insert twist. 3) It can be true bobbin lead, so the bobbin can spin faster than the flyer, and some of the problems of a flyer spinning at high speed are reduced. The net results are that one can easily spin 560 yards of 5,600 ypp (75 wpi) single with 9 tpi in an hour, and spinning/plying a 500 yard entry for the longest thread contest is an easy day's work. (E.g., one can easily spin 45,000 ypp singles at 150 yards per hour.)
The downsides with DRS are:
Higher ratios should indicate that more twist is being inserted to into the yarn. IN THEORY, for any wheel, the diameter of the drive wheel is fixed, so smaller whorls should mean more twist is being inserted?!?!?! NO! Smaller whorls mean there is more slippage. When you get down to the tiny whorls of "lace flyers", a lot more slippage! My tachometer told me that my fancy lace kit did not spin any faster or insert any more twist than my standard bobbin, and the double drive kit inserted more twist than the lace flier, but when I tried to speed up the double drive, by making smaller whorls, speed actually went DOWN, DOWN, DOWN. Deep thought indicated that there are good physical reasons for this related to vibration waves in the drive belt so smaller whorls have much less contact with the drive belt and much more slippage. This is an effect that dominates lace flyers in modern spinning wheel making.
You get a big wheel with fancy lace flyers, and lace production is -- disappointing. First, they are Scotch Tension, -- the drag of the tension system must be overcome before you can spin anything. And, that fine lace yarn that you want to spin must absorb enough twist to become strong enough to overcome the drag of the Scotch Tension, and that is a huge hurdle. I often spin yarns that are so fine (grist greater than 30,000 ypp) that they need more than 15 tpi to have any strength. Certainly some twist can be stored in the leader, and that can be transferred to the proto-yarn before the proto-yarn must overcome the drag of the tension system, so the proto-yarn can maintain yarn lock and receive twist from the spinning bobbin. I took my tachometer around, and most modern wheels with Scotch Tension insert twist at much less than 1,000 rpm. I can do much better with a drop spindle, and I am not even very good with a drop spindle.
Modern DD wheels are a bit better in terms of delivering twist to the proto-yarn, but are desperately tricky to adjust the drive belt tension so the bobbin spins faster than the flyer, but drag on the whorls does not slow the whole system to a crawl. However, a lot of things can go wrong in a DD system that will slow the system way down: too much drive belt tension, too little drive belt tension, wear on the drive belts, wear on the whorls, lack of drive belt dressing, drive belt dressing accumulating on the whorls, are all things to monitor every few hours of spinning. DD systems have rightfully earned a reputation of being high maintenance. Which is not to say that I did not LOVE my DD, when I got it.
The obvious solution is to design a clockwork system so the bobbin spins fast to insert twist, and the flyer spins slower to wind the yarn onto the bobbin, and to wind yarn onto the bobbin no faster than twist is inserted. Such a system was invented in Florence, Italy in the 13th century for use in the silk production industry. It was the size of a room, and required a man and a boy to operate. A century later it had been reduced in size so one person would use it for spinning worsted, and it remained one of the most valuable trade secrets in the world.
In essence, a DRS wheel is a double drive spinning wheel set up as a clockwork mechanism with the bobbin whorl just enough smaller than the flyer whorl, that the bobbin spins fast enough to insert twist as the flyer winds yarn on to the bobbin at the proper rate so each segment of the yarn has the correct twist. This concept has THREE important advantages. 1) It relieves the spinner from having to control twist, so all spinner needs to do is draft to the correct grist. 2) It reduces drag and slippage in the spinning system, so much less labor is required to insert twist. 3) It can be true bobbin lead, so the bobbin can spin faster than the flyer, and some of the problems of a flyer spinning at high speed are reduced. The net results are that one can easily spin 560 yards of 5,600 ypp (75 wpi) single with 9 tpi in an hour, and spinning/plying a 500 yard entry for the longest thread contest is an easy day's work. (E.g., one can easily spin 45,000 ypp singles at 150 yards per hour.)
The downsides with DRS are:
- you need to know what yarn you want to spin
- you need the correct whorls for the yarn you want to spin
- you need to be able to draft to a consistent grist
- you need to keep drafting as long as the drive wheel is moving or the yarn will break off
I have 5 whorls containing about a dozen "grooves" that I store on the wheel, and which allow me to spin almost any yarn I might want to spin, and I have more whorls in the spin chest. It takes me about 3 minutes to swap whorls. I can spin the singles for all of the knitting yarns that I commonly spin with just 2 whorls containing 6 grooves.
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1 comment:
Hi, Aaron.
Please DON'T post this - this is the only way I have to ask if I could possibly arrange to see your wheel/needles/sheaths in January in conjunction with another trip from the East coast, where I live.
First, some asides:
1. Really appreciate all this hard work and sharing - thanks so much. :)
2. The latest ONE - TWO - THREE posts were a nice summary.
3. I have left several thoughts as I read through chronologically. These were just reactions - I really don't care if you don't post them (reactions to years-old posts, after all), and I hope I don't seem a clueless pest. I was just moved to say something now and then as I read through the notes.
4. Your theories about fiber handling make sense to me. I tuned out the no-content, unhelpful static coming from some who commented - it simply doesn't seem helpful to take sides at this late date or ever. The extreme emotional static was sad, but sometimes there were some useful bits of content continuity in your responses. You experience continuous progress but the posts are intermittent notes to the file when you have something worth noting, and it is hard to put all the relevant details into posts, I'm sure. Plus, this is a blog, not a work for publication... :)
5. Regarding DRS - I really hope you take a look at the twisting device (named the "ewespinner") that Rav "easyspinner" has created and talked about in an espinner Ravelry group thread this fall (2018). The design almost looks like your DRS thoughts inspired it - two motors (DD), a controller to vary the rate at which each runs, the net result being an attempt at electronic control of the DRS.
He doesn't spin, so he doesn't understand that in addressing pet spinning peeves of his ex-wife (an easy-to-change bobbin and digital readouts of bobbin and flyer motor RPM so that she had some idea of her "ratio" to share) he has created something of potentially great value.
Put that together with your know-how of how to control for yarn buildup that affects DRS, and how to rapidly offload that fiber, and I am ready to propose a side trip on a transcontinental road trip to see my son in Berkeley: see your needles and wheel as well. He is a new 2018 PhD in Physics (Cornell), but I had to miss his May '18 ceremonies because my husband developed a serious set of health challenges (pacemaker/lead malfunction being the key factor). Spouse is better now.
Airfare is low in January. Might you be available in January 2019? At a guild meeting or just a coffee shop somewhere convenient to you? I have an unused Southwest Airlines fare from when I was going to go to a step-grandson's high-school graduation in Mountain View at about the same time as the PhD ceremony in Ithaca. (It all happens in May with kids... :) ). I'm thinking that I might be able to stop off at Clemes and Clemes, as well. I will comment again with the timing.
I'm dreynold1 on Ravelry - not a great spinner, but a practical one, and an open mind.
Have a happy December. Thanks again for your notes here.
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