Tuesday, December 02, 2014

Rabett Run: Ozone Photochemistry - Part 2

Rabett Run: Ozone Photochemistry - Part 2



Real science from an well known academic scientist who is near the top of  the publish or perish world.  Note: No citations.


Also note that (commenter) Dave did not pay attention in Atmospheric Chemistry (or bother to Google) and HO2 is a real entity in the real world.

History is longer than we thought

See: World's First Computer

http://link.springer.com/article/10.1007/s00407-014-0145-5
and
http://www.huffingtonpost.com/2014/12/02/antikythera-mechanism-older-than-thought_n_6254146.html?utm_hp_ref=science

It was well built.  Somebody had built prototypes.

Ah, Heck!!

EVERY branch of knowledge and technology has its own vocabulary.  It may use words from common language or from other branches of technology, but each branch of learning is likely to use the words differently.  Every branch of technology has its own terms of art.

The vocabulary of a technology is an index to the thoughts and concepts used in that branch of technology.  Without understanding the vocabulary, you cannot understand the technology.  Without a command of the technology's vocabulary, you cannot even ask intelligent questions.

Spinning is an archaic technology.  It's vocabulary has become obscure. However, if one is going to understand the concepts of spinning, then you need to know the vocabulary.

A beginning spinner may use an off the shelf wheel, but an advanced spinner will have goals that cannot be achieved with an off the shelf wheel and thus must know enough of the craft of wheel making to intelligently specify the wheel required.  At some point the advanced spinner needs to learn the vocabulary of the spinning wheel maker.


On the right, a hook that is not a heck.  On the left,  hecks that are not hooks and a hook that is a heck.

Knitting sheaths and knitting pouches revisted

For most of the last couple of years, I put aside my knitting sheaths and gansey needles in favor of  my leather knitting pouch and various other needles.

I like the knitting pouch with light, flexible needles  (stainless steel tubular) needles for lace. Certainly, cable needles offer some convenience, but for fast, low effort knitting the pouch wins over cable needles for lace.  The the pouch is very nice for soft fabrics knit from soft woolen yarns with needles in the range of 3 or 4 mm. (I no longer use needles larger than 4 mm, and thus am not speaking to their use.)

However, for fine, worsted spun yarns, nothing beats solid, spring steel used with a knitting sheath for fast low effort knitting. Above about 2.5 mm solid steel needles get very heavy, and then you are better off with tubular or wooden/bamboo needles and a knitting pouch.  At sizes below 1.75 mm the steel needles do not have enough spring force and  it does not matter whether  the needles are used with knitting sheath or a pouch. (However, a knitting sheath will always tend to damage tubular needles.) Thus, the virtue of the knitting sheath / spring steel needle is most apparent with needles in the size range of 1.75 mm -> 2.5 mm.

At this point, I design my yarns to be knit on needles in this range. My 5-ply sport weight is not as tightly plied as the commercial gansey yarns, so it is more splitty to knit.  Thus, my needles have gotten blunter, my stitches have less "pop", and things like bobbles are harder to knit.  However, the fine plies spread, and produce a more weatherproof fabric. These days, I knit hand spun, worsted 5-ply sport weight on rather blunt 2 mm spring steel DPN held in wooden knitting sheaths. Cast on for a snug fitting gansey to be worn against the skin is more than 400 stitches.

Gloves and boot socks get swaved using short curved needles that are rotated into the stitch using the same yarn.




Friday, November 28, 2014

Gold and Silver in Tapestries

The best argument for the timing of the spread and use of DRS spinning technology is the use of gold and silver in tapestry yarns.

Spinning such yarn is difficult to produce with good quality using the various kinds of spindles, or single drive flyer/bobbin assemblies, but is easy to produce using differential rotation speed controlled spinning equipment.  This can be easily demonstrated experimentally using the wire manufactured for wire wrap prototyping.  It is not cheap, but it is less expensive than real gold or silver wire, and has many similar physical properties to well annealed silver or gold (see for example https://www.hooverandstrong.com/bezel-strip-specifications).

Spindles and single drive flyer/bobbin assemblies tend to accumulate twist on a stop and go basis depending on the fiber's capacity to accumulate and distribute twist.  Metal wire does not accumulate twist.  The properties of  wire require a continuous process with no periods of yarn lock.  This is very difficult to achieve with spindles or single drive flyers, but is the normal and standard operating condition of DRS controlled flyers.

Thus, where we see industrial quantities of tapestry yarns being produced containing gold and silver, we can presume that DRS spinning technology was available.  This is reasonable, as such tapestry yarn production also used silk, which provides a direct link back to origins of the DRS technology in the Italian silk industry.

Anywhere you see gold or silver as part of the material in a tapestry, you can be sure that DRS spinning equipment was used to produce or wind the yarn.

Certainly wire can be core spun with fiber as in  http://myspinculture.blogspot.com/2012/10/fiber-wire-how-its-done.html or

Intertwined: The Art of Handspun Yarn, Modern Patterns, and Creative Spinning

 By Lexi Boeger.

However, one purpose of gold and silver in tapestry yarn was to provide more luster to the textile. Frequently, the gold or silver yarns were prepared by wrapping a silk core with a spiral of a flattened band of the metal.  This is the opposite of the modern "fiber-wire" craft.

Producing such yarns with a single drive system requires the takeup from hell, and some kind of a braking device on the silk core. However, once the width of the metal band is defined and whorls made, with DRS, the process is easy and fast.  Both the silk core and the metal band are supplied from reels. The metal band is wrapped around the silk with no twist inserted into to the metal band upstream from the point where the metal is wrapped around the core.  Twist is inserted into the core and must up run up stream from the point where the metal is wrapped around the core.  If the metal band is ~2 mm wide, then about 12 tpi are likely to be inserted into the core. The twist issue limits the use of short fibers such as wool and cotton.  With silk, one can start with -6 tpi, add 12 tpi and end up with 6 tpi which is reasonable. Short fibers cannot go through 0 tpi and remain competent. And a short fiber core with enough twist to be competent, will be over twisted if 12 tpi is added.

The elasticity of silk with the extensibility of the metal spiral make the metal wrapped, silk core lighter, stronger for its weight, and more weavable than solid metal or twisted filigree metal wire constructions. The need for elasticity for weaving limits the use of the bast fibers such as linen or hemp (a spiral metal band around a no-stretch core results in a rigid structure.)

The next time you see a "history of spinning", ask yourself if the history is consistent with the manufacture of yarn for tapestries.  The history of  tapestries with their known provence, industrial scale of production, and severe technical challenges are a good test for any history of spinning.

Do you really think some contract spinner in her cottage is going to have large amount of gold, silver and silk sitting around for making tapestry yarns?  Any history of spinning that does not include the production of tons and tons of tapestry yarns is incomplete.



Thursday, November 27, 2014

Stating the obvious and elucidating the trivial.

Everyone knows the two dowel technique for rolling rolags off of a drum carder.

However, when one is spinning finer, one needs thinner rolags.

I use the steel doffer as one dowel and a steel gansey needle as the other. This makes a smaller, thinner rolag.  Even when the rolag has been wound rather tight, the gansey needle slides right out, giving enough slack for the doffer to easily slide out.

My rolags weigh just under 5 grams, these days I spin them into about 50 meters of single. The rolags below do not look very uniform, but they average out.

When I have spun 2 rolags, I have about 100 meters on the bobbin and  I wind off before the effective diameter of the bobbin changes too much.  When I have done 10 rolags, I know I have about a hank, and I rewind, measure, and weigh.


40 rolags with doffer and 
knitting needle use to make them

I am sure that EVERYONE else has already worked out this trick, but just forgot to post it so the rest of us would know how to wind a smaller rolag that works better for spinning fine.

I am still a little surprised at how fast the process goes.  Working from batts that have been carded twice, it only takes about half an hour to card and roll the 40 or so rolags needed for an afternoon's spinning.  The result is some 2,500 yards of 5,600 ypp woolen single in ~6 hours.



Wednesday, November 26, 2014

Speed

I like cooking breakfast for my wife, but I do not spend all day cooking breakfast because breakfast must be done in time for work and play.

I like spinning, but I intend to get it done, so I have time for other things.   That means spinning fast.

It is not the speed that is important, it knowing how long it will take, and the "getting it done" that is important.

For me, spinning is just one step on a path to better textiles.

If you spin just for the purpose of using spinning to take up time, that is fine.  I do not care.  I am not writing for you.  I am writing for folks that want to make better textiles.  Just go spin and leave me to make better textiles.

This blog is written for myself and a very few, smart spinners. It is an audience that understands the naming and function of all parts of spinning tools including cap and ring spinning frames.

It is an audience that knows how to find information resources.

It is an audience that knows how to do all the math for spinning and weaving.

It is an audience that has (mostly) seen and touched my work at one time or another.  They give comments and suggestions in person.  I have found these to be of great help. The comments and suggestions of "Anonymous" have not been helpful.  My feeling is that Anonymous  is just an older version of one of those stupid teenage cliques that stand around being rude to everyone that is not just like them.  These are people that think their ignorance is as good as other people's facts.

However, spinning is performance based.  Facts always win out.   Someday, you will be walking around a fiber festival with your kids, and they will see me spinning, and they will ask, "Mom, how can he spin so fast?"   And, the truth will be out, some people spin faster than others.  Facts always win out.


Tuesday, November 25, 2014

Cross check

When I make a change to my wheel, I go back and check how it performs Scotch Tension and Irish Tension (single drive, bobbin lead).

Thus, I setup the new mother of  all  for Scotch Tension. RPM was about 65% of what I get with DRS, but net productivity was only ~ half for the 5,600 ypp woolen weft I am currently spinning.

Productivity for single drive, bobbin lead was better, and in the range of 70 % of  DRS. It must be noted that productivity was not as high as I would had expected for the achieved bobbin rotation speeds.

With the accelerator wheel and large whorls,  there was not as much difference between the performance of the #1 and #0 fliers as there is without the accelerator wheel and large whorls. The moral of the story is that: Small whorls have large slippage!

A second moral to the story is that gravity is a very good way to tension the drive belt, and that when the flier/bobbin assembly can move, vibration in the system is reduced.

However, the uniformity and grist control from DRS was distinctly better.  This may have just been a function of my spending more time spinning DRS recently, but given the higher productivity and better grist control of DRS, I am not going to put the effort into keeping my long draw and inch worm skills sharp.

Is the extra effort (and math) for DRS worth while? It means that I can spin/ply a hank of  5-ply gansey yarn in a day.That means I can spin the yarn for a sweater in a week and have a couple of days of knitting rather than spinning.  And, for big projects where I budget a thousand hours for spinning, it means that I have an extra 300 hours for weaving rather than spinning.    That is almost 8 weeks,  That is enough time to weave the yarn from (700 hours of fast spinning) or (1000 hours of spinning slow).  Thus, by spinning 30% faster, my weaving time is free. And, the quality of the yarn that I produce with DRS is much better, so my cloth is better.

The greatest comparative advantage in textiles is in better spinning.


Monday, November 24, 2014

The Balloon

If the yarn being spun is not under tension, it will "blow" out of the hecks on the flyer.

This is a matter of centripetal forces rather than aerodynamic forces.

It is not a problem with Scotch tension, and not much of a problem with Irish tension.

However, with DRS, if one drafts faster than than the yarn is being wound on the bobbin, then there will be slack in the yarn between the drafting triangle and the bobbin.  If one is spinning slowly, and working a good distance from the orifice, then the yarn may hang slack between the drafting triangle and the orifice. Onlookers accustomed to other spinning systems will be surprised.

At higher speed, the slack yarn will be pulled out of the flyer hecks and balloon  around the flyer.  This is only visible with a strobe.  In normal light, it looks like Scotch Tension with taut yarn between the drafting triangle and the orifice. In practice, it is very different because with DRS the yarn only winds on as the proper amount twist is inserted whereas with ST the yarn can wind on regardless of the twist.

On the other hand, DRS  wind-on can easily  generate enough tension to break off the yarn. With DRS, if one pauses drafting while the flyer/bobbin assembly is turning, the yarn will break off.  This can be frustrating to the point of tears, particularly as the spinner first begins to work rapidly.

However, at higher speed, one can draft, and store an extra foot or so of yarn as a balloon flying around the flyer.  This gives the yarn extra time to level and settle before being wound onto the bobbin. This yarn will be wound as the proper twist is inserted.   It also puts some slack in the system so that break off is not instantaneous if there is a pause in the drafting. At my current spinning speed of ~7 yd/minute, this gives me 2 or 3 seconds to fix a problem in the yarn.  At slower spinning speeds the balloon of  yarn around the flyer is less well formed, and more likely to tangle with the other arm of the flyer, bringing everything to a catastrophic stop.

With DRS, spinning faster may allow spinning some recalcitrant fleeces with fewer tears.


Saturday, November 22, 2014

Distance from drafting triangle to bobbin.

I am going to blandly assert that it takes some time for a drafted stream of fibers to "level" and "settle" into a competent yarn.

If one spinning slowly, this time is small enough to be ignored. However, as one spins faster, it becomes a consideration.

Then, one advantage of long draw spinning is that it gives time for this leveling and settling process to occur.  However, in a DRS system, one does not wave the yarn around, to give it time to level and settle. When spinning fast with a DRS system, one simply has to allow more distance between the drafting triangle and the orifice.

One can estimate the required time, by scaling off of Victorian texts on  (power) spinning and doing basic calculations.  At some point, the cap spinning technique of using a "balloon" becomes useful.  Balloons require a clear volume of space to operate.