thread count

[mournac]

I have to translate into French things like "320 thread count Egyptian cotton".

The problem is that the thread count in English is expressed in square inches, but it is in square centimeters in Europe.

How do I convert this, given the fact that the number of threads per square inch has to be different from the number per square centimeter?

Thanks,
René

[Knight]

I have to translate into French things like "320 thread count Egyptian cotton".

The problem is that the thread count in English is expressed in square inches, but it is in square centimeters in Europe.

How do I convert this, given the fact that the number of threads per square inch has to be different from the number per square centimeter?

Thanks,
René

There are 6.45 square centimeters in one square inch.
(one sqaure inch is 1 in x 1 in = 1 in², convert one inch to 2.54 cm, and you get 2.54 cm x 2.54 cm = 6.45 cm²)

Hence if you had 320 counts per square inch, (c/in²) that would be

320 c/in² / 6.45 cm²/in² = 49.6 c/cm²

[mournac]

Thanks for responding.
However, my problem is that I need to have the thread count per cm2.
If the thread count is 320/inch2, what would that count be for a cm2?

[Knight]

Thanks for responding.
However, my problem is that I need to have the thread count per cm2.
If the thread count is 320/inch2, what would that count be for a cm2?

There are 6.45 square centimeters in one square inch.

As stated above, to convert from threads per in² to threads per cm² you need to convert in² to cm²:

If you had 320 counts per square inch, (c/in²) you would lay that out as follows:

Code: Select all

320 threads | inch²    |
------------|----------|
      inch² | 6.45 cm² |

Now, Cancel like units. Inch² over inch² cancels out leaving you with:

320 threads
------------
6.45 cm²


Dividing 320 by 6.45 gives you 49.6 threads/cm²

[mournac]

Thanks William, that's just what I needed.

René

[Wiz.au]

Knight (William?), you need to be careful that you haven't used an "area" calculation for Thread Count.

Thread count is defined as the number of horizontal threads per measure, _ADDED_ to the number of vertical threads per measure. It is a "Count" of lines, not intersections as an "Area" or "Volume" calculation is.

Example:
A weave of 120 vertical threads in 1 inch and 150 horizontal threads in 1 inch gives the "Thread Count" of 270TC/SqIn (NOT 18,000)

In metric countries it has become the standard to use "10SqCm" (A square measuring 3.16cm x 3.16cm) instead of the "Inch Square" (A square measuring 2.54cm x 2.54cm) for Thread Count, mostly due to marketing reasons, as it makes the product look higher quality compared to the Imperical measurement.

So you would first have to find the number of threads per cm and extrapolate from this.

So from the example above:
120 vertical threads per Inch becomes
47.244 threads per cm => 144 Threads per 3.16cm

_ADDED_ to

150 horizontal threads per Inch becomes
59.06 Threads per cm => 187 Threads per 3.16cm

Giving a total Thread Count of
106TC/SqCm or 331TC/10SqCm

Your calculation gives the result of 41.86 which is incorrect.

The quick method used by a lot of textile mills is a conversion rate of 1.25 which in my example above gives a Metric Thread Count of 337TC/10SqCm from the orginal 270TC/SqIn, which is close enough for their grades. (80TC, 120TC, 140TC, 180TC, 200TC, 300TC, 400TC, 500TC,...)

[hkkc]

Can someone explain the thread count conversion quoted from the Chinese websites?
For example, T/C: 133*72,40s*40s and how it relates to the 300's 400's & 480's we have in Canada? Thanks.