Amount of Twist

What follows is from a handout that Peter and Jaque Teal passed out at SOAR'95 during their woolcombing class. While there is not a copyright on the materials, it would be incredibly tacky to use or print their table and not acknowledge them.

As a personal comment, the Teal's were wonderful instructors. If you want to learn to spin the yarn you really need for fine weaving, machine knitting, or truly long-wearing socks, I would highly recommend a workshop from the Teals.

This table details a rough and ready guide to the amount of twist that might be needed to produce a reasonable yarn using a run-of-the-mill average sort of fleece. Remember: It is only a guide to point you in the right direction.

Examination of the yarn will soon indicate whether you need more or less twist.

Wraps in 1 Inch
(wpi)
Rounded TEX Worsted Twists per Inch
(tpi)
Yards per Pound
(ypp)
Miles per Pound
(mpp?)
14 1700 0.5 3 280
20 880 1 3.5 560
25 580 2 4 840
30 440 2 4.5 1120
33 360 2.5 5 1400
36 300 3 5.5 1680
39 260 3.5 6 1960 1.1
42 220 4 6.5 2240
45 200 4.5 7 2520
47 180 5 7 2800
50 160 5.5 7.5 3080
52 150 6 8 3360
54 135 6.5 8 3640 2.06
56 125 7 8.5 3920
58 117 7.5 8.5 4200
60 110 8 9 4480
62 103 8.5 9.5 4760
64 98 9 9.5 5040
65 93 9.5 9.5 5320 3.02
67 88 10 10 5600
69 84 10.5 10 5880
71 80 11 10.5 6160
73 77 11.5 11 6440
74 74 12 11 6720 3.8

It cannot be emphasised strongly enought that all the foregoing data is very approximate. For instance, how tightly do you wrap the yarn aroun the inch measure? A tightly wrapped yarn will include more turns than a loosely wrapped one, and you can see that only a few turns make quite a difference to the calculations.

Having said that, if you always wrap your yarn with the same tension, although it might not produce the count indicated in the table, you will still have a rough guide to a twist that will provide a starting point for further experiments. Once you have discovered a twist thast gives you the handle you require, and assessed its variation from the table, that variation ought to hold good when you spin other counts from the same fibre--provided, as we said, you always wrap your yarn with the same tension.

What we are seeking is some indication of the twist needed, where no information previously existed.

Achieving the amount of twist is simple once you know the ratio of spindle whorl to drive wheel on your machine. To do that, place the crank at the bottom dead centre and turn one arm of the flyer in line with the mother of all. Tie a twist of yarn about it so that you don't confuse which arm you are counting and then turn the wheel through one complete revolution of the crank. However many revolutions your flyer made during that time (say ten) is the ratio of your wheel.

If you wish then to produce a yarn of 10 twists per inche (tpi) you draft (extend) one inch of fibre at each press of the tredle. 5 tpi would require a draft of two inches a treadle. 8 tpi a draft of 1.25 inches. All you need to do to find the required draft is divide the twists you require into the wheel ratio... 10/8=1.25, 10/5=2, 10/6=1.6 which is a bit more difficult so try 1.5 -- it will probably be so close that the result will be satisfactory.

A formula giving very similar results is contained in the "THE WOOLEN INDUSTRY" by Alan Brearley and John Iredale published by The Woolen Industries Research Association in 1965.

Twists per inch (tpi) = 106/Square Root of TEX Count.

So, for a TEX count of 150 we have: 106/12.2 = 8.6 twists per inch.

And that agrees very closely with the table.

With all such guides it must be remembered that the type of raw material, its end use and the ability of the spinner will all play an important part in deciding the amount of twist required. However, using these figures as a guide, samples can be spun and adjustments made until the required handle has been achieved. The results will then be reasonably constant for THAT PARTICULAR FIBRE. A change of fleece might well require fresh adjustments before a similar handle has been found. Have Fun!

If you have comments, please send email to: Rosemary Brock.

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