So, my first question, how do I calculate how many yards of each type of fabric I need? I have drawn out several of 'my own' ideas, but don't know how much fabric to buy for each type. Thanks!

I have EQ5, which calculates the amount of fabric needed. But I found that sometimes inaccurate, and for borders they calculate it the full length with no cuts.

EQ7 may be better. Also, there are so many different methods to making some blocks, some using less fabric. Half square triangles can be done so many different ways.

What I have done is work out the measurements, size and number of strips needed, with graph paper. Then I always add a little extra.

If you have a tablet or smart phone, there is a terrific app by Robert Kaufman called QuiltingCalc.

I use EQ7 which gives me yardage (like Patti says, it's not real accurate but is helpful).

One of the things I like about the QuiltingCalc is I put in the dimensions of the quilt and width of the border. It not only gives me yardage but tells me how many strips I need to cut. It lets me compare various sizes of borders side by side.

The best way I know to figure out your yardage
without a software program is to go through your design and see what size
pieces you need for each fabric. I would break down the drawing of my design
into blocks and see which ones repeat. Figure the yardage for one block and
then multiply it times the number of blocks you have in your quilt.

For example.....

Suppose your quilt is
made up of sixteen 12" squares.

This quilt uses six different colors but for the
purpose of this example, we are just going to look at colors 1 and 2.

One block looks like
this:

You have a 12" finished block that contains four
4" HSTs, you need to figure in the size square you need to create the half
square triangle. I always add 1" though the books say you need only add
7/8" to the finished size. If all HST's are from the same two fabrics, I
would need two 5" squares of Fabric 1 (purple) and two 5" squares of
Fabric 2 (yellow) or one rectangle 5" x 10".

Then Fabric 1 and Fabric 2 are also in the center
square. For color 1, you need 1 unfinished square that is 2-1/2". For
color 2, you need four rectangles that unfinished are 2-1/2" x 1-1/2"
or a strip 10" x 1-1/2".

Find out the area of the pieces you need. To find
that, multiply length times width. Then you need to figure what percentage of
each fabric you need from a yard for the one block. A yard typically has 1512
square inches if it is 42" wide.

So, for color 1, you
need 50 square inches plus 6-1/4 square inches. That comes up to 56-1/4 square
inches. Take that and divide it by 1512 and you get 0.0372..... I round that up to the nearest
percent so that is 4% of a yard for 1 block. Since that is for 1 block, you have to multiply it by 16 to find out
what you need for the quilt.

You get almost half a yard of Fabric 1. (.04 x 16
= .64).

You do the same thing for each color you have in
the quilt.

I'll do Color 2 and then you can ask any
questions that you want. We figured that we would need one rectangle 5" x
10" and one 10" x 1-1/2". That's 50 square inches plus 15 square
inches or 65 square inches total. Divide 65 by 1512 and you get .04298... or .05.
Now consider that you have 16 blocks. After multiplying .05 times 16, you get
.80 which sells as 7/8 of a yard.

So, for Color 1, you need 3/4 a yard and for Color 2, you need 7/8 a yard. Once you figure Color 3, you'll need the same amount of yardage for Colors 4,5, and 6. And remember since we rounded up, we may have a little more than we need. That's something I like in case I cut wrong or something like that. This figure also depends on the method used to make HST.

I hope this helps. If someone has a better way, let me know.

Thanks everyone for your answers! And thanks Roxana for the very in depth walkthrough! That helps alot!

Please note, Angel22, that I had to change my figures because I figured 12 blocks instead of 16! So take the version that is there now! Hope it helps you.

See Angel I told you this site is very supportive and knowledgeable. Roxana going to have to save this for when I loose my phone again and don't have my quilt and block fab.