Monday, January 05, 2015

Limits to spinning speed

One limit to spinning speed is how fast one can draft.  I would say that the limit imposed by drafting is on the close order of 8 to 10 yards per minute.  Certainly, one can draft much faster, but the quality of the yarn goes down dramatically.

One can draft woolen much faster, but woolen requires more twist, so the flyer/bobbin must rotate much faster.  1,700 ypp singles require only 4 to 6 tpi, so one can easily draft and spin these yarns well in excess of 8 yards per minute with a wheel that has a flyer/bobbin assembly running at 1,200 rpm.  I have little interest in these yarns, and have not explored the limits.

Thus, here you see that modern commercial wheels will allow one to spin worsted weight yarn as fast as is useful, and this is a rational for making wheels designed to spin at 1,200 rpm.

Lace weight singles (10s, 5,600 ypp) need 9 to 12 tpi depending on whether they are spun worsted or woolen.  Thus, a 1,200 rpm wheel spinning woolen lace singles is down to ~100 inches/min or ~2.7 yards/minute. However, lace weight singles can also be drafted at 8 yd/min, but you need a flyer bobbin assembly  running at 3,500 rpm to insert that much  twist and form a woolen lace single into a  competent yarn.  Looking at the last post, we know you are not going to get here with small whorls and a "screw tensioner" on your wheel.

Shirting weight yarn (40s, 22,400 ypp) was a common product made by traditional hand spinners for weaving.  A bolt of shirting fabric requires ~250,000 yards of yarn, so spinners spun a lot of this yarn. Typical twist is 17 tpi, so spining the 8 yd/ min that can be reasonably drafted requires a wheel running at almost 5,000 rpm.  These days my wheel has no problem running at over 4,000 rpm for sustained periods.  With my wheel, spinning the yarn for a bolt of shirting would be 6 months sustained and continuous full time work.  Having a fast wheel is no assurance that a spinning project can be done quickly. The amount of spinning required to support the weaving of fine fabrics is stunning. Shirting was also plied into hosiery yarns.

Yesterday, during the Dowton Abby bingewatch, I was spinning 10s from (commercial) combed long wool at between 5 and 8 yards per minute.  This was using DRS, so if my drafted grist drifted off spec., I would break off.  Thus, a yard of finished 5-ply yarn costs me ~ a minute, but during bingewatch, the minutes are free, so the yarn is free  :  )  Spinning 10s at 5 to 8 yd/minute can be easy.

Some lace spinners talk about spinning 30,000 ypp lace singles.  Worsted spun, such singles require ~20 tpi, so  I am happy to spin 5 or 6 yards / minute on my wheel, and a 1,000 rpm little Shetland wheel running at 1,000 rpm will produce ~50 inches or 1.4 yards per minute.

30,000 ypp (54s)  is far, far beyond cobweb. As a knitting yarn it needs to be plied, so finished yarn production is on the order of  22 yards per hour.  Much of what many lace spinners claim to be 30,000 ypp is no more than shirting weight. In fact, at one time the best Shetland lace sold to Victorian ladies was knit from 3-ply made up from shirting singles.  That has a grist of ~7,500 ypp compared to the 7,000 ypp of modern cobweb (e.g., http://www.shetlandwoolbrokers.co.uk ).  However the 3-ply is more stable, stronger, more durable, and more uniform. Compare also with the 12,000 ypp  Gossamer yarns from http://www.heirloom-knitting.co.uk/cart/ordergossamer_merino.php.  From this we see that commercial  "gossamer lace" is just 2 plies of shirting.    

Spinning shirting singles quickly and easily was, and is, a broadly and deeply useful skill.  However, it takes a wheel that inserts a lot of twist, fast.  Working on a slow wheel means the yarn tends to drift apart between drafting after drafting. It takes a lot more skill to spin shirting on a slow wheel than on a fast wheel.   I have great sympathy for anyone and everyone that spins such yarn on a slow wheel.  Spinning shirting drove much of my effort in making a faster wheel.

Fines (70s and 80s, 45,000 ypp) require some 23 or 24 tpi to produce a competent worsted yarn. I am lucky to spin these at 4 or 5 yards per minute. These may be the finest yarns that can be drafted at a good pace. It is not that hard, there is plenty of time to draft, as one waits for enough twist to be inserted.  If twist insertion is too slow, then the yarn drifts apart.  This problem of the yarn drifting apart is a major barrier to spinning very fine yarns on slow wheels (or spindles) and a major reason why I think the old spinners had faster wheels.  My problems with these yarns is not in their spinning, but in handling the singles.

The question is not how fast can one spin, but how fast can one produce the yarn that is wanted.  The craftsman spinner dreams the yarn, and then develops the technology that makes producing that particular and specific yarn feasible.  And, differential rotation speed (DRS) is to the fine spinner, what a table saw is to the fine woodworker.  DRS makes spinning fine threads much easier and faster.




4 comments:

purplespirit1 said...

The question is not how fast can one spin, but how fast can one produce the yarn that is wanted.

Seriously, WHAT is the obsession with speed? What is it exactly about "how fast one can produce the yarn" is so vastly important? Especially since you've blogged that you're not making anything with all this yarn you're spinning, why is it so crucial to produce vast volumes of it quickly?

Also... I still don't understand your math about producing such fine yarn. I've bought yarn from spinners, and mind you it never crossed my mind to ask them how quickly they've produced their skeins, I've bought plenty of consistently spun warm yarn. Have you any proof that the yarn you produce is warmer or more durable or whatever than another spinner's?

Aaron said...

I make objects and go out and use them.

Try it. You will have less time for spinning knitting, but you will have more time for other things.

Doing other things is why I like to get my textiles done quickly.

I could just use store bought, but mine are better. Mostly of the time, I do use store bought, but sometimes, the best is barely good enough.

A handspun, hand knit gansey has ~150 labor hours in it, and at my billing rate, I could buy hundreds of Patagonia sweaters for the $ that I could make in that much time. However, the handknit gansey is much better than any store bought sweater. It is worth the effort - which is not to say that I do not try to find ways to reduce the effort.

purplespirit1 said...

Spinners and knitters do other things faster in order to have time for spinning and knitting. Spinning and knitting is an art and a skill that requires time, love, and attention. Anything handmade is not meant to be rushed to have it done properly.

If your focus is to do things faster, it doesn't automatically make it better. If you don't have or can't make time to do something properly and effectively, but rather trying to find shortcuts to making something, then you're doing it wrong.

That is the point that a lot of your responders are trying to make. Handmade should mean quality. You're more focused on doing things faster and - based on the few things you've shown - it clearly doesn't mean better.

"Doing other things is why I like to get my textiles done quickly."

Quickly, but obviously not well. Your emphasis is on speed. You keep posting about spinning faster, faster, faster - but rarely write about spinning better.

Faster is only better in a race. If you truly believe that quality handmade goods are only made based on the speed they're done in, then you're sorely mistaken. I'm not sure how to explain it in a way you'll get, since you're so obsessed with speed.

Aaron said...

Slower is not obviously better.

Slower is only better when the object is a conspicuous consumption of leisure - as in a rich lady in Queen Victoria's Court is bored and needs something to occupy her time.

The talented professional works quickly. Slower than an industrial factory, but much quicker than the merely competent amature.

Consider hand-spun, 5-ply gansey yarn. For some purposeses it is the better yarn, but it actually available! If I can spin fast enough to actually produce 5-ply for an object - then the object will be better. If I cannot get the yarn spun in time, then the object will be worse. Here, too slow is the worst of all worlds. In this case, making a better object depends on being able to spin faster. And, getting the singles actually spun, depends on having a wheel that will insert twist fast enough to actually produce the better singles. In this case, faster is better.

When one is spinning "fines" (30,000 ypp and greater) a faster wheel makes spinning easier because the singles get enough twist to become competent yarns before they have time to drift apart. Thus, a faster wheel makes spinning finer, easier. Again, faster is better.

Or, to say it another way, slower is harder. Why do I want to spin the hard way? And, you call me a Jackass? No, I am like a mule - I choose the easy path, and often it is faster.