Saturday, July 05, 2014

Spinning productively

Why, Oh Why, comb top, and then knock the fibers out of alignment before spinning?  It is doing the work twice.  No professional does the same job twice, unless they did a poor job the first time.  No the comb/diz did their job, but the spinner destroyed the alignment when held the fiber to keep the flyer/bobbin assemble from pulling the whole top into the orifice all at once, like a hungry grizzly bear eating a Big Mac.


Silly!! The spinner that knows their craft simply keeps the fibers straight, and aligned parallel all the way through the process. The combs /diz can align the fibers better than fingers hurriedly inch-worm drafting.  More, better, faster drafting to realign the fibers is not the answer. The Answer is: Do not mess the fiber up!

The answer is use differential rotation speed (DRS) so that fiber is drawn into the orifice only as fast as twist is added..When, I am spinning 10s at 9 tpi, my flier/bobbin assembly draws in 1/9" of fiber stream and inserts 1 twist.  I do not have to pull back on the fiber stream to retard its entry into the orifice, because it is only going to take in as much fiber as is needed for the twist that is being inserted.

Alden Amos and others have tried selling such wheels but there was no market.  Modern spinners do not have the skills to operate such wheels.  That is stupid because the concepts and math are fully explained in the spinning manuals from the beginning of the 20th century.  And, Alden Amos in his Big Book of Handspinning walks us through the math and concepts.

Still modern spinners insist on messing up their top by using Scotch Tension wheels, and in the discussion of what kind of wheel to buy there is no discussion of  DRS.Even Alden does not discuss the advantages of DRS in his big blue book.

When, I started using DRS, I thought that it was faster because there were 2 drive band contact areas, and hence more friction to drive the flyer/bobbin assembly faster.  And, that is certainly part of the story, but it does no explain the full increase on productivity.  The other side of the story is that DRS speeds spinning by making fiber in take much more efficient.  And, instead of a fiber drafting process there is a very efficient top/roving attenuation process.

So here is the deal. A DRS wheel is inherently faster than single drive wheel - and that includes e-spinners.
A double drive wheel that does not use DRS is somewhat faster than a single drive wheel, but not nearly as fast as a true DRS wheel.  And the difference between a not DRS DD wheel and a true DRS wheel is only millimeters - you cannot tell without measuring unless you work with DRS all the time.

My take is that any spinner that wants to spin productively, will put the effort into learning DRS; the concepts, the math, the tools, and the technique.  How productive is DRS?  Well, it will let me spin 560 yards of lace weight worsted spun single in ~70 minutes.  How long does it take you?  Yesterday, I was tuning my whorls, and running back and forth between the wheel and the lathe.  In the process, I spun a couple of thousand yards of lace weight singles.  How much did you spin yesterday?



4 comments:

Anonymous said...

Interesting. I can do the same thing with my bobbin lead, a fast whorl and long draw. I'm certainly not alone.

Aaron said...

Anonymous,

Do you really spin worsted yarn long draw?

Really? !!

The key words are "combed top".

Combed top held with one hand and fed into a single drive flyer/bobbin assembly will become disorganized due to the tension on the fiber bundle during "yarn lock" as twist is accumulated. Always!!


Woolen spun yarn can be spun long draw with one hand, but then the fiber preparation has a different fiber alignment which is not impaired by fibers being orthogonal to the line of yarn formation. In fact, more orthogonal fibers improves the woolen character of the yarn.

Anonymous said...

Yes, Aaron, it is combed top. Yes, Aaron, I know precisely what combed top is, having been in the fiber producing and processing business for over twenty years. And no, it doesn't become locked and no, the fibers don't become disorganized, because I know exactly how to do it.

It is not woolen. It is worsted. I know several other spinners who do the same. It takes skill and practice.

Just because you can't do something... don't assume it can't be done. Just because "people" have told you it can't be done, don't assume they're right. Isn't that your motto?

Aaron said...

Do the physics.

If the top is not disorganized, then there is no need for drafting, only attenuation.

Single drive wheels and DD with slippage apply a constant tension on the drafting triangle. Holding the fibers to oppose that tension disorganizes the fibers. There are a number of engineering solutions (including DRS)- used by mills. Most hand spinners do not solve the problem, but merely whine about the effort required to spin worsted singles finer than 11,200 ypp. I freely admit that the problem is less with low grists and slow speeds.

As you spin finer gristes and work at higher speed the problem becomes more acute. It is a problem that must be solved before one can spin 22,400 ypp worsted singles (40s) at 2 yards per minute. I spin 40s at twice that rate on a routine basis.

Now, how fast do you spin 40s? (Easy test: spin 100 yards, and it should weigh ~2 grams.) The test takes me less than 30 minutes, and I come out it with a bobbin of hosiery single.

We may have discovered why you do not spin finer and