Math gurus please help. How do I cut my fabric?

I have finally decided on a pattern for a quilt for my own bed. I've been quilting for the years now. It's about time. I want the quilt to be made from one block. I have figured out what size pieces to cut to make the block finish at 10" square. I have 20 fat quarters each measuring about 18"x 21".

Can someone help me figure out how to cut each fat quarter to get the most yield? How many blocks can I make? I have a king size bed. I think I need at least 90 blocks. I will add some length and width with a wide border. I have an extra yard and half of a one of the prints that can be incorporated into the blocks if needed. I won't be using the fat quarters for the background (snowballs).

Each block requires
4 - 4 1/2" squares for the main fabric
4 - 2 1/2" squares for the contrast squares
1 - 6 1/2" rectangle for the plus sign
2- 2 1/2" squares for the plus sign

and 8 - 2 1/2 " squares from background fabric for the snowballs. Bonus points if you can tell me how much fabric I need for snowballs for 90 blocks and to border the quilt to make big enough for a king size quilt.

Here's a picture of my test block. These are not the fabrics I will be using.

Before you get into this, I am concerned that 20 fat quarters is not going to be enough for a king size bed. 20 fat quarters is really only 5 yards of fabric. I think you will need more than that. Most king size bed quilts require at least 9 yards of fabric for backing, I think you would need near that amount for the top. You will have waste cutting the fat quarters.

I calculate how much will be needed by looking at square inches. 20 fat quarters is 8316 square inches. Your 90 10" blocks will require 9000 square inches. So at the very least you will need 3-5 more fat quarters. Then you need to figure out what colors you need for each section of the block. Then factor in that there will be waste with curing from fat quarters.

No bonus points for calculating yet for me!

Thanks Jean. I have two extra pieces of fabric that can be used for the blocks. One is 1.5 yds, the other is 1 yd. I was going to use the 1 yd cut for binding, but I can use all of it it in the blocks. The "blades" for the main part of the block don't all have to be one color per block. I'm okay with the blocks being somewhat scrappy in that sense. The quilt I will be making is similar to the X and Plus quilt from Zen Chic pictured here. I don't have the pattern, plus I don't want my blocks to be too small, so I figured out what size to cut the pieces on my own.

I can also add more fabric from my stash if needed. I am sure I have something that will coordinate. Or worst case scenario, I can try to find more fabric from the same line.

I'm pretty good at math, and I have no clue how to figure this out. But I do have an idea for you.

Cut the pieces you've listed out of paper. Then play with the paper pieces on the fat quarters until you have the least waste. It will give you a good visual, and you'll know when you're using the fabric well.

Let us know how it goes!

Quote:

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Originally Posted by GuitarGramma

I'm pretty good at math, and I have no clue how to figure this out. But I do have an idea for you.

Cut the pieces you've listed out of paper. Then play with the paper pieces on the fat quarters until you have the least waste. It will give you a good visual, and you'll know when you're using the fabric well.

Let us know how it goes!

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Great idea, Toni!

Here's my whack at it.

Main fabric: Cut 4.5" strips across the 21" side (you'll have a little strip left over at the end), then subcut 4 from each strip at 4.5. You can get 16 4.5" squares from a fat quarter (4x4.5=18).

Contrast squares: You will need to cut 2.5" strips along the 21" side. You will get 8 strips (8x2.5=20), then subcut 2.5" on each strip. You will end up with 7 from each strip for a total of 56 2.5" squares from each fat quarter.

Combine the 6.5" and 2.5" blocks for the plus sign. If you add those it is 9", so cut along the 21" side the 18" width. You will get 8 18" strips that you will then subcut into the 6.5 and 2.5" pieces. So each fat quarter will yield 8 plus signs.

If you are using yardage (not fat quarters for the snowballs, you can get 16 2.5" squares out of WOF (assuming 42" wide). If you need a total of 720 total (90 blocks using 8 each) then you will need 45 strips at 2.5 each. That is 3.125 yards or 3.-1/8 yards. I'd get 3-1/4 or so just for squaring up.

Okay, someone else check my math!!

Quote:

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Originally Posted by LRM

Here's my whack at it.

Main fabric: Cut 4.5" strips across the 21" side (you'll have a little strip left over at the end), then subcut 4 from each strip at 4.5. You can get 16 4.5" squares from a fat quarter (4x4.5=18).

Contrast squares: You will need to cut 2.5" strips along the 21" side. You will get 8 strips (8x2.5=20), then subcut 2.5" on each strip. You will end up with 7 from each strip for a total of 56 2.5" squares from each fat quarter.

Combine the 6.5" and 2.5" blocks for the plus sign. If you add those it is 9", so cut along the 21" side the 18" width. You will get 8 18" strips that you will then subcut into the 6.5 and 2.5" pieces. So each fat quarter will yield 8 plus signs.

If you are using yardage (not fat quarters for the snowballs, you can get 16 2.5" squares out of WOF (assuming 42" wide). If you need a total of 720 total (90 blocks using 8 each) then you will need 45 strips at 2.5 each. That is 3.125 yards or 3.-1/8 yards. I'd get 3-1/4 or so just for squaring up.

Okay, someone else check my math!!

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You da math guru! Looks good! It would be easier and less waste to cut this from yardage.

I hate to admit it, but I find the math part fun. Yes, I'm a propeller head like that!

Thank you ladies the help. I ordered another yard and half in fat quarters. I think I have enough fabrics for blocks. I am concerned that I don't have enough fabric for the background and border. Gotta do some shopping.

Please post photos as you progress. This looks like a fabulous quilt!

Quote:

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Originally Posted by GuitarGramma

I'm pretty good at math, and I have no clue how to figure this out. But I do have an idea for you.

Cut the pieces you've listed out of paper. Then play with the paper pieces on the fat quarters until you have the least waste. It will give you a good visual, and you'll know when you're using the fabric well.

Let us know how it goes!

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That is a terrific idea! I never thought to do it with fake fabric...hehehe! Thank you for this post.

I googled your question about cutting FQs. I also remembered I'd printed off a FQ cutting diagram & found that in my notebook. Go to nickelquilts | Quilting Blog by Pat Speth. Since I don't know how to do the link, enter May 17, 2012 in the search box. On another web site, UCreate, they list how many squares you can get out of a FQ:

6 - 6.5" squares
9 - 6"
12 - 5.5" or 5"
16 - 4.5"
20 - 4"
30 - 3.5"
42 - 3"
56 - 2.5"
99 -2"

I've made several Turning Twenty quilts; these use 20 FQs, which makes ~ a twin size quilt.

Good luck with your project.

Just an update, I bought more yardage and fat quarters. I think I have enough fabric now. Thanks for the input ladies.

Give this calculator a try....
Quilter's Paradise - The Leader in Laser-Cut and Pre-Cut Kits and Services for the Quilting Market

Thanks Cheri- the problem I have is that I am cutting several different sizes from each fat quarter. I have decided to just wing it and proceed. So far, I have had good luck cutting with not much waste. I thought about buying the pattern, but the quilt size of the pattern is 83x83 which is smaller than I need. I also already had the fat quarters and I don't know if the pattern calls for yardage or FQ's so I decided to figure out the block on my own and go from there. I will post progress as the blocks start coming together.

That calculator is great though, so I will bookmark it. Thanks.

Have you ever tried the quilting calculator? It will tell you how much binding , how many blocks, and the yardage to buy all you do is put in the width and the length of the fabric and it does everything else for you . Math is not my subject so I found this app by RK it's a free app, and it helps me so much, If you want to buy one you can but I must warn you the R about $40.00 so I opted for the free app. I luv it, good luck