Sunday, February 26, 2012

Bobbin Winder

I spin on a little spinning bobbin, and then I suck the spun yarn off  (technical term meaning wind off  : ) with a bobbin winder that is a bobbin stuck on a tapered dowel that is chucked into a cordless electric drill.  It is fast and it works.

At Stitches, somebody wanted a bobbin winder to wind off (Suck yarn off of) her little wheel.  I told her my solution and she said, "But I do not have a tapered dowel !"  So I went home and turned her a nice tapered dowel.

 However, This morning at the Chinese market a chopstick would work.  And they do!




Here I show use of wooden takeout chopsticks, but the cheap plastic re-usable are even better.

Monday, February 20, 2012

Spindle vs. wheels


I say, " wheels can be faster than spindles." That is not a value judgment, that is a demonstrable fact. Spinning slowly may be a meditative activity, like yoga, and I do not say that meditation is bad.  I only say that, "I want the most thread in the least time."

Humans use toys to learn skills. Toys are an essential good. Children use dolls to learn child care skills without endangering an actual baby. I used spinning toys to learn basic skills. The Traddy as it come out of the box was a toy.  As tweaked and fixed, it is a very fast wheel.  Playing with that wheel, taught me how to "fix" a wheel. That was good.  I used spindles with a wooden whorls to lean basic spindle skills.  That was good.  However, basic physics told me that there where ways of getting a (drop) spindle to go faster, and to spin finer.  I looked, and did not see such spindles on the market, so I made faster spindles myself.   (http://gansey.blogspot.com/2011/10/spindles-and-spindle-whorls.html )  Playing with wooden spindles taught me to make faster spindles that spin finer.  And, I will say that such spindles spin disconcertingly fast and are not suitable for beginners. I do not say they are better, I only say that they are faster and allow spinning finer.

How can anyone dismiss this technology without trying it?  I cannot patent it, this technology is at least 3,000 years old.  It was in use in the Highlands of  Scotland within living memory. And, it is in use in South America today.  Anyone that talks about South American spinning tools and does not mention removable metal whorls is not telling the whole story.

Spindle advocates say, that if I would just practice, then my spinning with a spindle would be as fast as my spinning with a wheel. OK!, let's assume that I practice until I have perfect spindle technique and my wind-on operations require zero time.

With respect to supported spindles, if one is spinning 6,000 ypp, then 5 yards per minute requires ~180 revolutions per minute. If one is spinning 12,000 ypp (110 wpi) at 5 yards per minute than one needs about 400 rpm on a sustained basis. That approaches the upper limit of hand spindling. Yes, you can get instantaneous speeds in excess of 2,000 rpm, but that is not the sustained average speed over a work day or work week. (Of course, the flier on a stock Ashford wheel cannot sustain such speeds either.)

However, I have fliers for my wheel that will sustain average speeds of more than 2,500 rpm. My wheel has produced more than 2,000 yards of worsted 12,000 ypp singles in an 10 hour day. No spinner with a spindle can do that. When we get to serious lace at 35,000 to 40,000 ypp (200 wpi), then a spindle will produce twist for a maximum of about 2 yards of single per minute, while spinning at my wheel,  I am still limited by my drafting ability to about 5 yards per minute.

The the numbers above dramatically understate how much faster a wheel spins compared to a spindle. If we look at reality, even the best spindle spinner must take some time to wind-on. Thus, in reality a hand driven spindle is very much slower than a properly setup wheel. Anybody that says differently, likely does not understand how to select and setup a wheel to achieve good spinning speed. Anybody that says differently should be ready, willing, and able to show that they can use their spindle to produce more than 2,000 yards of worsted 12,000 ypp singles in an 10 hour day. I am perfectly willing to show anyone how to hand spin 2,000 yards per day of 12,000 ypp worsted singles in 10 hours on a wheel. Let me use a Studio Gaustad Motor Spinner, and I can go much faster. The numbers above prove that no amount of practice will make any hand driven spindle as fast as a properly setup wheel (or driven spindle). This is not about me or you, this is physics.

People say that I do not like spindles and that is just not true. After I had a good, fast wheel, I put a lot of effort into finding a spindle design that allowed me to spin much faster than I could on the stock/standard wheels at a LYS. Given my choice of of those strictly stock wheels or a spindle of with a removable metal whorl, I would take the spindle because it is faster. However. let me put new bobbins on those wheels and do a couple of other tweaks, and suddenly the “fixed” wheels will be much faster than the spindle. Anybody that says a spindle is faster than a wheel does not know how to set up a wheel for faster spinning.

If we look at garment weight, worsted thread (9,000 ypp to 15,000 ypp) and consider ergonomic factors for a full time spinner over a period of years, then the wheel will spin a great deal more thread. In the 18th century, when all spinning was done by hand and there were huge numbers of full time professional spinners, it was a common rule of thumb that a spinner with a wheel could produce 7 times as much thread as a spinner with only a spindle – and that was a spindle with a removable metal whorl. To me, that number seem a little high, but it could be correct because professional spinning wheels in those days had two fliers allowing spinners to spin a thread with each hand. See for example http://gansey.blogspot.com/2011/10/double-flier-spinning-wheels.html .

I am old, and my wrists are weak. I must consider ergonomic factors. If I want as much thread as possible over my remaining years, a wheel is my best choice, but that is just me.

Saturday, February 18, 2012

Science, spinning, and illusion

For a long time, one of my jobs was to evaluate technologies, first for Bechtel and its clients, and later for the US Department of Energy.  Large capital investments and the health and safety of large numbers of people were on the line, so the reports had to be correct.

As I started spinning, I looked at the technology technology of spindle spinning with all of the rigor that years before I had applied to technologies related to disposal of hazardous oil refinery wastes and zinc refineries.

One of my conclusions was that the use of a half hitch as taught by Abby Franquenmont (and as she learned as a child in South America) limited the fineness of the yarn that could be spun with such spindles and/or limited the the size of the copp that could be managed.  I reported my conclusions below and somebody asked on a thread on Ravelry, if those conclusions were correct.  There was a lot of back and forth.

Abby had to defend her long held style of  spinning, so she set up an illusion, purportedly to test the physics, in the same way that 19th century snake oil salesmen purported to test the laws of medicine.

Her little test did prove two things.  Unless one takes special care, hand spun yarn is not uniform.  She should have taken Amos's class on spinning to a standard back in the days when it was offered.  The second is that when loosely spun wool singles are subjected to tensile stress to the point of failure, first the single stretches, then the fibers drift apart.  Every spinner that looks at what they are doing knows this.  Abby used this to present an illusion that pretended to be science.

Physics says that a half hitch will reduce the strength of a half hitch by about 40% in an  axial load, and this is based on the difference in load on the inside and the outside of the radius as the yarn wraps around itself  in the knot.  Abby choose a load direction that minimized the difference between the inside and the outside radius.  However, this is not the direction of the load that occurs during spinning.  This is physics, and in physics, the direction of the forces matters.  That is why we learn to use force vectors. Abby should  have paid more attention in physics and calculus.

If you have a fairly uniform wool yarn, tie an overhand knot in if and pull on both sides, the yarn will break at the knot.  However, with a half hitch the force on the spindle side of the line is reduced by friction as the yarn spirals down to the copp.  In the case of the half hitch  the failure starts at the knot and runs between fibers away from the spindle (and half hitch.)  The actual break occurs a few fiber lengths away from the knot.  Thus, the failure of the yarn appears to be 1-6 inches away from the knot depending on the twist, ratchet, and  staple length. This is indeed what Abby found.

I would say that Abby's little illusion absolutely demonstrates that a half hitch reduces the strength of  a woolen yarn, despite her attempt to minimize the effect by changing the geometry of the stress to minimize the knot effect.



Tuesday, February 14, 2012

Large needles

I like the fabrics produced by fine needles, and thus I have not been making the needles/adapters for large needles.  I have suggested that users of large needles can reduce the stress on their hands by simply dropping  down a needle size.  I was wrong, and I am sorry.

I do not do commissions, however my SIL's 60th birthday is coming up and she wants a cowl.  She has been asking for this for a couple of years, now she is saying that I must do it for her big birthday.  The pattern calls for large needles.  I got out my old cables and swatched. It did not look very good. I was up until midnight making adapters to use those big old  DPN in the bottom of the stash needles with a knitting sheath.

Next morning, sure enough, it looks my knitting again.

I will make adapters to use large needles with knitting sheaths. 

Thursday, February 09, 2012

Esty

I have stopped obsessing over spinning, and am again making knitting sheaths and needles that are listed on Esty.

There are some new tools in the shop and I have learned to do some things faster meaning that prices are down.