Thread Sizes, Systems and Conversions

All threads and yarns (with the exception of monofilament 'fishing line' threads and some glittery metalised polyester threads) are made by spinning lots of individual fibres together to make a 'singles' yarn which is inherently unbalanced. To make the thread balanced 2, 3, 4 or more singles are then folded (plied) together to make a balanced thread. Occasionally this second spinning is intentionally tight and a second folding/plying takes place to create a very firm but balanced thread.

The size of a thread is indicated by the thickness of one of the 'singles' used to produce it, and modified to indicate the number of plies. There are several systems in use for measuring the thickness of a thread or yarn, and historically many more systems were used, especially in the wool producing areas of Britain.

With threads measured by an indirect system the number will be divided by the number of plies, ie:
60/2 Nm which means a two ply thread; one 1,000 metre length of each ply will weigh a sixtieth of 1Kg, so a 1,000 metre length of the plied thread will weigh a thirtieth of 1Kg.
30/3 NeC means a three ply thread; one 840 yard length of each ply will weigh one thirtieth of one pound, so 840 yards of the plied thread will weigh one tenth of a pound.

Some manufacturers of cotton threads state the thickness as 2/60s or 3/40s - which means the same as 60/2 or 40/3.

With threads measured by Tex or dTex the number will be multiplied by the number of plies, ie:
Tex 35 x 3 which means a 3-ply thread and each 1,000 metres will weigh 105gms

Threads measured by denier do not usually account for the number of plies, ie a 60 denier thread will weigh 60x9000gms per 1,000 metres regardless of whether it is a singles, a 2 ply, 3 ply etc.

Traditionally filament silk and its synthetic substitutes (rayon and nylon) are measured by denier. Cotton and spun silk threads are measured by English cotton count (NeC or CC) and linen threads are measured by English linen count (NeL). The textiles world is slowly moving to the metric count (Nm) and Tex/dTex systems.

Then there is the thorny issue of Ticket numbers!
A ticket number is a manufacturer's way of identifying a thread product but it is not an accurate way of denoting the size/thickness of the thread.Ticket number can be based on cotton count, metric number or tex and it 'assumes' that the thread is 3-ply. Thus ticket number 30 could mean a 30/3 thread - or it could be a 20/2 or it could be a 60/6 they each contain the same amount of fibres per metre. Add to that the fact that Tex and Nm sizes are bracketed into groups for ticketing purposes and the size is rounded down to the smallest of the bracketed group. It should come as no surprise that two threads from different manufacturers can each have the same ticket number but be rather different in size.

Because there are so many different systems in use lacemakers and other textile hobbyists have a need to compare the thicknesses of threads and yarns with a single formula.
My'Threads for Lace'book uses the informal wraps per cm system, derived from the wraps per inch used by weavers. It is also fairly easy to measure the tex of a resultant (plied) thread or yarn.

K n o w n s i z e	C o n v e r t t o
		Tex	dTex	Denier	Metric No	Cotton No	Linen No
	Tex	-	Tex x 10	Tex x 9	1,000 ÷ Tex	591 ÷ Tex	1,654 ÷ Tex
	dTex	dTex ÷10	-	dTex x 0.9	10,000 ÷ dTex	5,910 ÷ dTex	16,540 ÷ dTex
	Denier (den)	den ÷ 9	den ÷ 0.9	-	9,000 ÷ den	5,314 ÷ den	14882 ÷ den
	Metric No (Nm)	1,000 ÷ Nm	10,000 ÷Nm	9,000 ÷ Nm	-	0.59 x Nm	1.65 x Nm
	Cotton No (NeC)	591 ÷ NeC	5,910 ÷ NeC	5314 ÷ NeC	NeC x 1.69	-	NeC x 2.8
	Linen No (NeL)	1,654 ÷ NeL	16,540 ÷ NeL	14,882 ÷ NeL	NeL x 0.60	NeL x 0.36	-

Measuring Wraps per cm

All that is required to determine the wraps per cm (w/cm) of any thread is a piece of paper about 8-10 cm long with two parallel lines drawn exactly 1cm apart.
I use the computer to draw the lines but careful hand drawing would work. Fold the strip ofpaper several times so that the drawn lines run across the folded paper.
Wrap the thread around the paper strip, outside of the lines, several times to anchor it then make the first wrapping on a line. Continue to wrap so that the
wrapped threads lie parallel, just touching each other but not overlapping and with no gaps. Count the number of wraps needed to completely fill the space between
the two lines. Repeat the exercise as many times as necessary to be sure that you have counted correctly.

If you need to know the thickness of the thread for lacemaking purposes refer to the charts on this page.

Measuring Tex

To measure the Tex of a yarn (the resultant plied yarn rather than of a single ply) you will need a balance or scales capable of weighing accurately in milligrams. Usually
sold as jeweller's scales one of these costs about £20. Ordinary kitchen scales are not accurate enough.

To determine the Tex of any thread carefully measure 10 metres of it and cut from the reel. Now weigh it.
Tex = weight in grams of 1,000 metres of thread, so multiply the weight of your 10 metres by 100. That figure is the Tex of the yarn.

In her book Contemporary Lace for You Jane Atkinson has recorded the Tex along with a lot of other useful notes about a wide range of threads
suitable for lacemaking. The tables of her findings are available on her website along with a lot of other observations about the threads, although I
suspect that most of theTex sizes stated are those quoted by the manufacturers rather than her own findings.

MainLacePage§ LaceGallery§ LacePattern§ Bibliography§ PaperBobbins§ LaceLinks§ ColouredThreads§ CurlyLace§ SnakesGallery§ VariegatedThreads§ BookmarkVariations