Friday, September 18, 2015

Raging Ignorance

The great thing about wraps per inch is that the square of WPI (when done well) is grist in yards per pound (ypp). With small corrections, it will also work for cotton, hemp, and silk.

Then the square root of grist (in ypp) is the diameter of the yarn in inches.

This relationship is useful in knitting and weaving because if I know the grist, I know how thick the yarn is.  It is useful in spinning, because if I know how thick the yarn is then I know the grist.  It is an easy calculation.

However, it requires that in measuring WPI, the yarn must be packed to refusal.  Learning to do WPI correctly takes real practice.  It is a "SKILL"!  One starts with yarns of known grist and practices measuring WPI until the WPI is the square root of grist.

Now there are a bunch of knitters that claim wpi should be measured more loosely, then they have a little chart to show them the class thickness of the yarn.  Well, if they measure WPI loosely, then they have lost the relationship with grist. All they have is their silly little chart, and their silly little chart does not help spinners and weavers.  It does not even help serious knitters.

Many, many knitters have put their loosey-goosey approach on their blogs until the first few pages of a search for WPI only brings up that silliness.  Now, the authoritative information is buried. 

Here is a good example where hobby knitters have managed to lose and bury useful, traditional knowledge about textile production.  Isaac Asimov told us at the Institute of Man and Science, "Americans think their ignorance is as good and anyone else's facts!".  Today day I would rephrase that to "Knitters think their ignorance is as good as traditional knowledge"!

My favorite single is 5,600 ypp (10s) or 75 wpi.   I have a little brass gauge that I can set to a gap of 0.25 inches.  I can be spinning, and if when I pack the gauge to refusal, and there are ~19 wraps, then the grist is very close to 5,600 ypp.  It works.  I have done this hundreds of times.  I check grist as I spin, and wind hanks of 560 yards, and the hanks are within 5% of the desired weight. It is faster, easier, and more accurate than a McMorran Yarn Balance!  Sometimes I spin 40s (22,400 ypp), then I know that when packed to refusal and there are ~38 wraps in the 1/4" gauge, and the hank of 560 yards will weigh very close to the desired 11 grams.

I ply the 10s up into 5-ply, and sure enough I get ~30 wraps per inch and I know the grist is very close to 1,000 ypp. It works for  sock yarns, gansey yarns, and Aran years.  However, it only works with a wpi gauge and "PACK TO REFUSAL".  It does not work when you wrap the yarn around a ruler or a dowel.

It is less suitable for "art" yarns, but that is no reason to throw the whole concept away.  Some day, we will want to go back to practical knitting and we will have forgotten the traditional knowledge that make it possible.

1 comment:

08ca768e-6860-11e5-81c9-f3919a0beea2 said...

I'm interested in your research but don't understand why you put energy into demeaning other fiber people (eg, repeated use of the word "silly"). Your approach is very scientific, but that isn't the only way to gather or quantify knowledge. The combination of scientific approach and rather immature defensive attack on "inferior" methods is confusing and makes it harder to pull out the useful info from your blog. I tend to straddle the scientific/intuitive line and often see a gulf of misunderstanding between the two types. A lack of respect for others' learning and teaching styles can leave us blind to lots of good information. Today I didn't want to work on filtering out the bias against other (women?) fiber people so I won't have the benefit of the knowledge you intended to share. Maybe another day...