Filet crochet

[wundermann]

About how much size 8 thread is needed to make a long sleeve filet crochet blouse?

[Granny Square]

There is no way to answer that question accurately, it would depend on the size, design of the blouse, and how lacy the fabric is, and your individual stitch tension.

I believe size 8 thread is a perle cotton size, or at least I've never seen a mercerized 'doily cotton' in that size, the latter comes in 3, 5, 10, 20, 30 and in higher numbers divisible by 10 but hard to find nowadays.  (the bigger the size #, the smaller the thread).

Here is a thread (ha!) here from 9 years ago that discussed the difference.

If the info there is correct, 8/2 perle cotton is the same as laceweight, so probably close to #10 mercerized bedspread/doily cotton (guessing?)

I'd suggest making a swatch say 6" square in straight DC, unravel it and measure the yardage you used.  Let's say 20 yards (no idea if that is reasonable, just a number to calculate with as an example, you'll need to do that swatch for the right number).  A 6" square is one-quarter of a square foot.  So you would need 80 yards for 1 square foot.  (the reason for swatching in DC versus a filet openwork pattern - it's better to guestimate on the high side of the thread requirement, it may be difficult to get the same dye lot - yes that matters in thread, even white.  

Take a blouse out of your closet and measure it, calculate how many square feet comprise the front, back, 2 sleeves, and multiply that by your real number that equates to my hypothetical 80 yards.

Edited August 26, 2021 by Granny Square

[Granny Square]

Some very rough yardage ideas from patterns using thread, could  not find any with long sleeves.

Short sleeve, pineapple pattern trim, sizes from 28 to 50" bust, 1200 - 2400 yards

Roxy, short sleeve, fairly open pattern, roughly same yardage as above

Cool, short sleeve, a bit of openwork, 2250-2850 yards, 36-48" bust sizes

Driftwood, open pattern, a bit long but still short sleeves, 1616 -4040 yards small to 4XL

Coral Popcorn, doily-like, 1800-2000 yards, 3/4 length sleeves

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