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    Old 08-21-2017, 07:31 AM
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    Default Mathematically Challenged...

    And, I can't "conceptualize" either.

    Maybe someone can help.

    I need a backing for a quilt and the backing needs to be 80" by 56". I want the seam to run horizontally, across the width of the quilt, not vertically, along the length.

    How much fabric, at a regular 45" do I need to buy?


    Thanks, Watson
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    Old 08-21-2017, 08:16 AM
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    Originally Posted by Watson
    And, I can't "conceptualize" either.

    Maybe someone can help.

    I need a backing for a quilt and the backing needs to be 80" by 56". I want the seam to run horizontally, across the width of the quilt, not vertically, along the length.

    How much fabric, at a regular 45" do I need to buy?


    Thanks, Watson
    Try looking at some of the backing material at Marshall Dry Goods. Backings come in 90 and 108 wide, so a couple of yards will do. No seams.
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    Old 08-21-2017, 08:17 AM
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    My method. Most fabrics have usable about 40 inches wide. Most times it doesn't matter whether you do WOF or LOF.

    So divide 80/40 = 2 widths to make your length.
    2 widths x 56 inches = 112 inches total length of fabric
    112 inches divided by 36 inches in a yard = 3 yds (108 inches) + 4 inches = 3.11 Yds.
    Round the .11 up 1/8 (4.25") or 1/4 (9 inches)

    Edited to add: When I make my backings like this, I use a 1/2 inch seam allowance and iron the seam open. This takes most of the bulk out of the seam.

    Last edited by Barb in Louisiana; 08-21-2017 at 08:21 AM.
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    Old 08-21-2017, 10:03 AM
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    Using Barb's calculations, I'd buy 3.5 yards. It might shrink a little when you launder it before use and you need extra on the ends - I like at least 2 inches (4 inches for 2 ends) , sometimes 3 (6). With a longarm, you might need more. (Remember to double the amount you allow for each end). 3.5 yards = 126". You need 112 + 1 for seam + 6 for ends=119", so 3.5 yards doesn't too allow much for shrinkage.
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    Old 08-21-2017, 10:35 AM
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    For starters, I would also "assume" that the fabric only had 40 inches usable width.

    Are you planning to have it long-armed? How much "extra" will you need?

    If I was doing the backing and needed 5-inches extra all around, I would buy 5-2/3 yards of fabric and would have leftovers.

    I would also wash it before cutting it.

    But I just checked - and you live in Canada where fabric is more expensive (usually) than in the USA.

    I don't remember if you are in the wash before cutting group or not -

    Anyway - I have found some fabrics have shrunk over two inches in width - some have shrunk over two inches in length - very very few that have not shrunk at all.
    Attached Thumbnails backing.jpg  

    Last edited by bearisgray; 08-21-2017 at 10:40 AM.
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    Old 08-21-2017, 10:51 AM
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    I also would choose a wider backing. Would save money in the long run. There is a lot of 90" and even 118" at reasonable prices.
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    Old 08-21-2017, 10:57 AM
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    I agree that the wider backing would be easier - and probably less expensive, in the long run.
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    Old 08-21-2017, 11:01 AM
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    Cotton sheets from the thrift store...no seams and less $$$.
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    Old 08-21-2017, 11:52 AM
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    I use the Robert Kaufman quilt calculator app. It gives yardage for both vertical and horizontal piecing.
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    Old 08-21-2017, 11:56 AM
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    Thanks everyone.

    I had already figured in the extra for long-arming, so I'm OK that way. I bought everything they had....3.7m, so that's just over 4 yards.

    Thanks, again!

    Watson
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