Help with fabric calculations
 

Hi,
i am trying to figure out the fabric I will need for a whirlwind quilt. The directions to make a 12 inch whirlwind block say to cut 1 strip 5" X WOF fabric 1 and 2. Sew the 2 strips together. sub cut the strips into 9" squares, then slice each square in half diagonally. then use 4 triangles to create a 12" block.

I want to make a queen size quilt with sashing between the blocks. I am so confused!

Please all you seasoned quilters help out a newbie!

Can’t help but when cutting your angle, same fabric must always be on top or the “spin” will be the opposite way.

Ok, talking it out while I type. For those that have already had their coffee, correct me if I counted or multiplied wrong.

So with one WoF, you should get 4 9" blocks, plus a pretty good hunk of scrap. Very unlikely to get 5 blocks, most fabrics I figure with a usable 40-42" width. It will take 2 blocks to make the 4 triangles so you will get 2 blocks per WoF.

As Tranum said, watch the spin! Always cut from the same side of the fabric in the same direction. I just did a project and had I folded the fabric I would have gotten half the pieces unusable for my design. I write myself a big note on a full piece of typing paper with a diagram and something like "right side white on top, cut left to right" in big letters.

Ok, so there is no one set size for a quilt. I'm usually aiming for about 100 inches in length, and about 80+ inches in width for a queen sized.

6x7 12" blocks is a pretty good place to start. That would make it 72x84 without sashing or a border. Add 14" for 2" sashing across, for 86" wide. 16" for the length which puts you right at 100". You can use less blocks and wider sashing or add a border as well.

6x7 = 42, and you get two blocks per WoF, so you need 21 WoF rows, or 105" which would be 3 yards (108") of each fabric if you use only two fabrics -- note: That does not include the sashing. And that works out exactly to the 6-12 yards that I expect to use to make a queen sized quilt!

Otherwise, you should be able to get the two blocks out of a fat quarter (watching your cutting).

All I know is it will be beautiful.

Since this is a "math" question I will not be able to help you. However, I want to say that is going to be a beautiful block & if all the others are similar, I'm going to love, love, love that quilt. I'm not quite understanding about the spin of the block & how to cut the fabric but I'm not going to worry about that unless I decide to make a block like yours. :) Sometimes things just don't click in my brain like they should. :hunf: Can we see the progress of this quilt as you move on with it?

Thank you IceBlossom! I had a major brain freeze and could not figure this out! I got the pattern from a free site - I hope it is ok to post it here
https://www.sewcanshe.com/blog/2016/...nd-quilt-block

I haven't decided if I want the florals all the same or to have a variety. I am excited to have fun at the fabric store!

How did you cut the pieces for the block that you have pictured?

I tried to follow the instructions you gave - and I was unable to duplicate the look of that block.

Bearisgray, here's how this method works. Each 4 squares will give you two
Twin Sister blocks but one will be the negative of the other.

http://vroomansquilts.blogspot.com/2...-blog-hop.html

Found a different method to make all the blocks same instead of negative/positive
but it does not involve strip piecing. It can also be paper-pieced. :)
http://www.blocklotto.com/2019/03/ap...-twin-sisters/

That I understand . Thank you for the link.