eeraemore

Thank you everyone for all of your input!! If it helps, this is what I am trying to make as the final block: http://www.quiltingboard.com/t-141590-1.htm. With this question (post), I'm focusing on the middle "diamond." I took a 4 7/8 square of the light green, made a half square triangle, and did the same for the dark green...then sewed them together to make the middle diamond! I've been thinking about this for over an hour. My head hurts. :)

sushi

Call me crazy, but this is one of reasons I loved piecing quilts! Color, creativity, and the challenge of figuring it all out! And yes, I am a believer that math is beautiful! (If you doubt it, check out tessellations, fractals, et al.)

PaperPrincess is correct in reducing the starting lengths of sides A and B of the triangle by 1/2" to 4 3/8". (I was wrong in reducing them by only 1/4".) Her calculation of 6.18" (~6") looks right to me as the finished size of the block. (While I enjoyed reading it, I don't agree with the next step she took, however, which reduced the block to 5".)

I am thoroughly enjoying the other ways that people are approaching this question! Vive les differences! (One proof of math's beauty is that it works no matter which way one comes at it.)

eeraemore, PLEASE let us know what you learn from experience!!!

Thanks!

LyndaOH

I think you're having trouble because you are trying to find a math formula for using half square triangles to make a quarter square triangle square. The two don't easily mix.

I think what you should do is use quarter square triangles. Take two squares that are 7 3/4" square - one of each fabric. Cut them diagonally twice. This will still give you the 4 7/8" triangles, but the bias edges will be in the right place. I used 7 3/4" because it's 6 1/2" plus the extra 1 1/4" you add as per the standard formula for quarter square triangles. Your center block will finish at 6 1/2" which is just a smidge larger than the 6.45" that your center should be, based on a 12" corn & beans block.

Does that make sense?

LyndaOH

Actually there's only 1/4" from each triangle, because there's only one seam on one leg of the triangle, so you were right that it's 4 5/8" and about 6.5" finished.

sushi

Now I love this discussion even more! :-)

Holice

I'm glad I took too Aleve because all this makes my head hurt. To begin with there does not appear to be complete information. However, in rereading your original post which says you cut a square of 4 7/8 inches and then cut the square into a triangle. My quiltmaking knowledge tells me that the intention is to sew two of the triangls together back into a square. With the 7/8" the assumption is that you are going to sew them together with an accurate 1/4" or scant 1/4" seam which will make your square 4.5"
However your illustration does not show a half square triangle square. So something is missing. So I don't understand your original question related to what size you should square up the square, according to your description it should be 4.5". Your illustration does not match your description. To my knowledge no instructions assume trimming down unless they tell you to. 7/8" is the basic addition to sewing triangles into square. I've talked enough.

LyndaOH

Just to clarify, this will make a finished square of 4" - unfinished it will be 4.5".

If you look at her illustration, what she's doing is taking half square triangles and sewing four of them into a square.

Val in IN

I'm with Holice, this gives me a headache :-|

GrannieAnnie

Actually there's only 1/4" from each triangle, because there's only one seam on one leg of the triangle, so you were right that it's 4 5/8" and about 6.5" finished.[/quote]


I've loved math all my life HOWEVER--how do you take a square that is 4.835, cut it in half ---even with the other square attached and get a square that is almost 2 inches larger?

I've still not been able to see her picture, so that may be part of my problem.

LyndaOH

She is taking two squares that are 4 7/8", cutting both in half and then making a larger square out of the four triangles from both squares.