Thursday, August 10, 2017

Getting the Gist of Grist



I have been spinning not quite 4 years.  I have spun miles of yarn and enjoyed every inch of it.  I have knit with it and woven some and am pleased how forgiving the yarn seems to be.  All my hiking socks are knit from handwoven.  They fit well, breathe well, I get far fewer blisters and they last.

BUT there is one thing that eludes me.  In all my reading and video watching, the following statements are made: handspun is more dense than commercial and if you want to make a specific yarn you have to pay attention to grist.  These statements are contradictory AND no one really seems to address how to really control grist.

Grist is basically yarn density and is usually described in terms of length per weight, such as Yards Per Pound (YPP) or Meters per Kilogram.  Since I have knit decades more than I have spun, I prefer to express grist as meters per gram, because I can then relate that more easily to skeins, which usually come in 25, 50 or 100 gram weights.  (M/Gr = YPP/496.5)

So after I have spun, plied and washed a skein, I measure the length in meters and divide by its weight in grams.  Unfortunately, although it looks and measures perhaps as a fingering weight (16-18 wpi), the grist more often tells me that it’s more a sport or even a DK weight.  Fingering weight usually is somewhere between 3.5-4.5 m/gr, sport weight is more like 3-3.5 m/gr, DK ranges from 2.5 – 3 m/gr and worsted weight is 1.5 to 2.5 m/ gram.  These are approximate and don’t totally jive with the Yarn Council numbers, but they work for me.  The problem comes when knitting with yarn.  The gauge and resulting fabric behaves more according to grist than according to yarn diameter.  Makes sense – you can only compact fiber down so far.  So basically the novice spinner substitutes twist to achieve diameter rather than concentrating on grist.  I have come to the conclusion, if you spin to grist, the diameter takes care of itself.

So how do you achieve desired grist?  The McMorran balance often is mentioned, but that is only a spot sample.  I have done something similar – created a little balance from wire, put a length of a sample yarn of desired grist on one side and the same length of my project yarn on the other.  If they balance, their grists are the same.  But that’s only a spot sample.  Not really useful over the course of a project.

So here what I have been doing.  I haven’t done this enough to know if this consistently works, but it should. First I decide what grist the final yarn is to have.  For example, I want a sport weight of 3m/gr.  It’s to be a 2 ply, so 3*2 means the singles grist should be 6m/gr.  Since I prefer a backward draw – whether short for worsted draft or long for woolen – I can measure a comfortable make – like 45cm (about 18 inches).  If 1 gram of fiber is to measure 6 meters, then 600cm/45 cm per make = 13 to 14 makes. I am aware that final length won’t be what the stretched length while spinning is – I figure at least 10% length reduction.  So I shoot for a slightly higher number of makes to take that into account – 15 makes would probably be better.  If you use a forward draw for worsted, you'd have to measure about how much you draw out each time and go from there.

  I play with this until I understand what this grist looks and feels like.  I repeat this every so often to make sure I am staying more or less at this grist.  I then worry about twist and do ply backs to see if I like what I see.  I adjust pedaling rate and/or whorls if I don’t.  I do not worry about diameter – I figure the grist will take care of that.  

The question is, if this is a reasonable approach or not – feedback most welcome!

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