Go Back  Quiltingboard Forums >
  • Main
  • Could someone explain something to me, please? >
  • Could someone explain something to me, please?

  • Could someone explain something to me, please?

    Thread Tools
     
    Old 05-22-2012, 11:32 PM
      #1  
    Member
    Thread Starter
     
    Join Date: Nov 2011
    Posts: 57
    Default Could someone explain something to me, please?

    I have been reading an article about organizing your stash and came across a line that said, basicallly- a finished square is 1/2 inch smaller than the original cut square. So if I have a 4 inch square, taken out of my red box, after sewing it to other squares, it should measure 3 1/2 inches - that is using 1/4 inch seam allowance. The accompanying illustration has the original square attached on all 4 sides.

    ****Why is the finished square only 3.5 inches and not 3 inches if you are sewing all 4 sides using a 1/4 inch seam allowance? After all, you are taking 1/4 inch off all 4 sides and 1/4+1/4+1/4+1/4=1***

    I know math is not my strong suit, but am I that weak in it?

    thank you so much! the things you think about when you have insomnia

    Debbie
    callie8799 is offline  
    Old 05-22-2012, 11:40 PM
      #2  
    Super Member
     
    katesnanna's Avatar
     
    Join Date: Aug 2010
    Location: Brisbane, Australia
    Posts: 3,453
    Default

    Because you only take 1/2inch from the length and 1/2 inch from the width.
    katesnanna is offline  
    Old 05-22-2012, 11:44 PM
      #3  
    Super Member
     
    Join Date: Feb 2010
    Location: Maryland
    Posts: 3,586
    Default

    Because you are only taking 1/4" off EACH of the 4 sides. left and right, top and bottom.
    virtualbernie is offline  
    Old 05-23-2012, 02:19 AM
      #4  
    Super Member
     
    sandyl's Avatar
     
    Join Date: Mar 2010
    Location: Delaware, Ohio
    Posts: 1,355
    Default

    OH, I love this! This is indeed something that would keep me awake nights, too. It sure makes sense that 1/4 x 4 is 1. But when you split them up (1/4 on each side) it does boggle my mind, too. ......I hate math and always have-I usually call in help (DH).
    sandyl is offline  
    Old 05-23-2012, 04:25 AM
      #5  
    Senior Member
     
    happyquiltmom's Avatar
     
    Join Date: Jan 2012
    Location: NE Indiana
    Posts: 564
    Default

    Try it on a scrap of fabric and you'll get a visual of why it is true. You take 1/4" off the left, and 1/4" off the right, which adds up to 1/2" horizontally. Then you take 1/4" off the top and 1/4" off the bottom for a total of 1/2" vertically. So, your 4" square ends up being 3 1/2" at the end.
    happyquiltmom is offline  
    Old 05-23-2012, 04:41 AM
      #6  
    Banned
     
    Join Date: Mar 2010
    Location: Sturbridge, Ma
    Posts: 3,992
    Default

    A similar case happened to me many years ago about the 7/8" added to a triangle.
    I had to cut a square - say 6", then divide it diagonally into a triangle, then add the 1/4" all around and then measure the base to the tip of the diagonal line. It was 6 7/8". Then it all came clear to me.
    Holice is offline  
    Old 05-23-2012, 04:59 AM
      #7  
    Power Poster
     
    Join Date: May 2008
    Location: MN
    Posts: 24,643
    Default

    Originally Posted by Holice
    A similar case happened to me many years ago about the 7/8" added to a triangle.
    I had to cut a square - say 6", then divide it diagonally into a triangle, then add the 1/4" all around and then measure the base to the tip of the diagonal line. It was 6 7/8". Then it all came clear to me.
    This is the one I had to draw out for myself, too.
    Attached Thumbnails triangle.jpg  
    bearisgray is offline  
    Old 05-23-2012, 05:38 AM
      #8  
    Super Member
     
    Join Date: Jul 2010
    Posts: 1,789
    Default

    Yeah the 7/8 was confusing for me too. Once I drew it out i became clear.
    bakermom is offline  
    Old 05-23-2012, 07:15 AM
      #9  
    Super Member
     
    Join Date: Nov 2010
    Location: MS
    Posts: 2,624
    Default

    This reminds me of my sister and I calculating measurements for an isolette cover. She's a nurse and I do accounting. We both calculate things in opposite ways. We just cracked up laughing while laying out our measurements...To hear us "arguing" over how to do it and both of us said this isn't rocket science!!
    Nanamoms is offline  
    Old 05-23-2012, 09:05 AM
      #10  
    Member
    Thread Starter
     
    Join Date: Nov 2011
    Posts: 57
    Default

    First, thank you for the responses... I'm coming to the conclusion this is something I just need "to do" and not think about. if I need a certain size finished square, I just need to cut the fabric 1/2 inch larger than I need for I am taking a 1/2 inch off the width and length. If I need 1/2 square triangles, I need to add 7/8"... (going to make a cheat sheet at home)...

    but I just can't get my head around the reasoning (tell ya, I'm not good at math reasoning) if I taking a 1/4 inch off each side (1/2 " total for width and 1/2" total for length) that still gives me 1" taken off for seam allowances. why isn't that calculated- for 1/2 off width + 1/2 off length = 1").

    ugh. guess there are some things I will never understand and that's why we have cheat sheets.... but now I know why my current quilt has gotten wonky...

    thank you! :
    callie8799 is offline  
    Related Topics
    Thread
    Thread Starter
    Forum
    Replies
    Last Post
    dreamer2009
    General Chit-Chat (non-quilting talk)
    31
    06-19-2011 07:07 PM
    Margie
    Main
    4
    02-03-2010 02:46 PM
    grma33
    Main
    11
    01-26-2010 06:15 AM
    minstrel
    Main
    26
    09-15-2009 06:54 AM
    middysmom
    Main
    8
    09-22-2007 03:39 AM

    Posting Rules
    You may not post new threads
    You may not post replies
    You may not post attachments
    You may not edit your posts

    BB code is On
    Smilies are On
    [IMG] code is On
    HTML code is On
    Trackbacks are Off
    Pingbacks are Off
    Refbacks are Off



    FREE Quilting Newsletter