Threadcount: bedsheets vs. shirts

[alchimiste]

This afternoon I've seen bed sheets with threadcounts in the 700 region. How is this calculated?

Mathieu

 

[Mike C.]

Thread counts for the most part are BS. Even high end makers fudge the numbers sometimes.

 

[Alexander Kabbaz]

This afternoon I've seen bed sheets with threadcounts in the 700 region. How is this calculated?

Using a dartboard and a blindfold.

 

[ROI]

When I was just a pup, I learned that the "count" measurements for apparel textiles and domestic (sheets, for instance) textiles were calculated differently. For quite a while I kept the entry from The Fairchild Dictionary of Textiles that explained the difference. I doubt I can quote it precisely now, but the gist of it was that the "thread count" number used in domestic textiles was what most of us intuitively think it is. You take one square inch of the cloth and count the ends vertically and horizontally. The total number of yarns is the thread count. You may have seen little devices with a magnifying glass perched above an inch square window that is used to count the threads in cloth.

The book explained that the method of arriving at the 60s singles, 100s two-ply, etc., that are commonly used on shirt fabric is entirely different. The measurement starts with a standard weight measure (an ounce, 100 grams, I don't recall) of combed cotton. The quantity of cotton is then spun out to the desired thickness measured by strength. The linear measure of the yarn produced translates into the familiar numbers. Say, spinning a yarn 100 meters long would be a 100s singles yarn. Longer staple and heartier cotton will produce a longer or stronger yarn, thus, a affecting the number. All the factors fit into a calculus of gains in fineness balanced against losses in strength, and so on.

After going through the arduous process of measurement, textile people doubtless developed analytical shortcuts. Sensitive measuring instruments (that Eli Whitney didn't have) have probably obsoleted the original method. The lone vestige is the now (as Alex Kabbaz suggests) the nearly meaningless system of awarding numbers signifying we-know-not-what and pricing accordingly.


Apparel counts

 

[Alexander Kabbaz]

Normally used to describe spun (staple fiber) yarns, the English yarn number or English cotton yarn number indicates the number of 840-yard lengths in a pound of yarn. The lower the cotton yarn number, the heavier the yarn.

The yarn number is usually shown in conjunction with the number of plies, e.g., 60/1 indicates yarn size 60, one ply (also referred to as "60's"), while 60/2 indicates two size 60 yarns, plied (also referred to as "60's two").

Yarn number has nothing to do with thread count. Most good broadcloths are made of two-ply yarn. Many good broadcloths have a construction of 144 warp yarns x 76 weft yarns per square inch. That is a total of 220 yarns per square inch. If those are two ply yarns, some makers will then say that there are really 440 yarns per inch. It is really all just so much B.S.

Yarn number is important.
Number of plies is important.
Thread counts? Dartboard & blindfold.

 

[ROI]

Yeah, like I said.

 

[alchimiste]

Yarn number has nothing to do with thread count. Most good broadcloths are made of two-ply yarn. Many good broadcloths have a construction of 144 warp yarns x 76 weft yarns per square inch. That is a total of 220 yarns per square inch. If those are two ply yarns, some makers will then say that there are really 440 yarns per inch. It is really all just so much B.S.

I guess this is how the very large numbers I've seen for bedsheets were obtained.