Wednesday, July 20, 2011

Corner Triangles and Setting Triangles....

My Log Cabin On Point - Critter Community Quilt is pieced and I am hand quilting....but I thought {in case you want to make a log cabin on point of your own} I should post the formula for figuring up those pesky corner triangles and setting triangles....

For the Corner Triangles...I needed to cut a square in half once on the diagonal.  This way my stretchy bias would be on the long edge which was sewn to the 4 corners of my quilt...

to figure out what size you should make the parent square {which will be cut once on the diagonal} follow this formula:
1. Take your finished block size X 1.41
2. Divide that answer by 2....and ADD 0.875".....then round up to the nearest 1/8th. inch to find the parent block size
3.  Take the parent square and cut it in half once diagonally to yield two corner triangles.  You will need two parent squares cut once on the diagonal to yield four corner triangles.

I had a 10" finished block my parent square was 8"

Now, along the sides I needed to add Setting Triangles.  For Setting Triangles I needed to take a square and cut it twice diagonally.  This gave me four triangles with the straight of grain along the long edge {which would be my outside edge}. 
To figure the size for the parent square in the Setting Triangles....follow this formula:

1. Take the finished block size X 1.41 and round this answer up to the nearest 1/8"
2. To the  answer in step 1....ADD  1.25 inches....this is the size of your parent square for Setting Triangles
3. Cut a square this size and then cut the square in half twice diagonally.

So for my 10" finished block size....I needed a parent square for my Setting Triangles that was 15 3/8 inches.

Hope this helps if you decide to do a quilt on point!

For today...I am going to try to finish quilting this baby and maybe **fingers crossed** get it bound!

Here is a little peek at the back....I am lovin' the back!!!

Have a great Wednesday!


  1. You know my eyes just glazed over with all those calculations, right? Just kidding. This is such a cute quilt, and the black polka dots are perfect for all the bright colors!

  2. Thank you very much Mary! This is very helpful.

  3. Looking fabulous indeed. Can't wait to see it finished.

  4. That was WAY too much math :) but the quilt is fabulous!!

  5. I am so glad you posted the formulas. With such pretty pictures too!

  6. I married an accountant so I wouldn't need to do sums - Mary I need to get him to do me a chart!

  7. Good on you for posting this. It took me a few quilts to realise why people talked about bias, half trianges, quarter triangles etc. I am really loving your quilt!!

  8. Oh, dear! I better go write that all down....hopefully, I'lll remember where I put it when I need it! The quilt is darling and, of course, what wouldn't be with dotty setting triangles...can't wait to see the whole shebang!!

  9. very useful info.. to be filed in my "how to " folder. Thank you so much. It might help fix a quilt i didn't get right the first time and with my "Farmers wife"

  10. Your lovely hand quilting is really going to finish this off beautifully! When my mind recovers from a serious case of jetlag, I'll have another look ! Thanks fro doing all the maths!

  11. I only have one quilting book!!
    And it doesnt cover hand piecing.

    In fact I just recently got 'the' book off the shelf, and it currently resides on my lounge floor.

    I thought of you actually, because you asked what inspires me, this book does.

    I shall write a post soon.

    Just sewing up my patchwork cushion!
    (still taking me all day, between the digging and cake eating!)