I'm thinking of using some of the fabric I already have and doing like a disappearing 9 patch quilt.

My only problem is how do I figure out the size of the quilt, or do I just make pieces as I go until I get it to the approx size I want it?

If you use 5" squares to make it, the finished block is 13". The one I'm making now is 4.5" squares that finish up to 11.5" blocks. You can make them any size, but those are 2 sizes I've done them.

these 2 sizes, are the sizes i use most for the D9P.

then with the 13 (which will actually be 12.5" finished)..i went 5 blocks across (62.5") by 6 down (75")
= 30 blocks. add a border or 2. so basicly, thats how you figure it out..

what size finished quilt were you thinking about doing?

13" is the finished size. When looking at the D9P block, there are 3 seams in the middle, which "eats" 1.5" from the block, plus 1/2" allowed for seam allowance around the block (1/4" each side) means that you have 2" taken from the total inches (15" for 5" blocks). That would make your example 65" x 78".

thanks ..i was actually just trying to help her figure out a quilt size,and how to calculate. i should of known when you put "finished" size..what you meant. lol

i usually just make the blocks,lay them out, and go from there on the quilt size..adding here, adding there... :roll: no real measurements! :shock:

So, How many squares do I need to make the quilt this size? I am wanting to do this with a group and are not sure what to tell them. If it is a planned one how much yardage do I need? Please help.

Unless you are working with an exact finished size of the quilt I have to calculate based on the ease of cutting the initial square for the 9 patch. If you work from the other direction then your cut pieces may require weird sizes which I don't want to have to do. So consider this:
If you want a 12" finished block, then the D9P will end up being 11.5" Therefore you loose 1/2" on the finished size when making it D9P.
In your example of wanting a finished 13" finished block (13.5" unfinished)
Each square for the initial 9 patch should be cut 4.83" which is a little over 4 3/4". So the decision when cutting should be to cut the squares at 5" (up a bit) or down to 4.34". So your decision whould be to make the quilt a couple inches larger or smaller than intended.
So my point is to make it easy and make your calculatations based on the regular 9 patch and not what it will be as a D9P. Is it time to take an Excedrian at this point.
I'm wrestling with this right now for a project for a class and trying to decide how many squares to cut and what size.
Regardless of the size you still begin working with a block that is divided by 3.

exactly! if it is a regular pattern..then i know what size i will end up with and fabric yardage.

picking out a block,i want to do, is another thing. i wouldn't know how to figure out yardage..someone here with an EQ program can tell you..

It's a whole lot easier to adjust your final size of the quilt with borders than to drive yourself nuts with crazy measurements on the block itself. Make it easy on yourself and do 4.5 or 5" squares.

Thanks everybody!

I originally wanted to make a quilt from a pattern in a book for my baby, but can't afford to buy the fabric, so figured I could use what I already have in my stash to do like a D9P and make it crib sized or about there.

For each d9p block you make, you need 9 5" squares. I would either make it 3 x 3 (for about 39" square) - which would use 9 D9P blocks or 81 5" squares- or make it 3 x 4 (about 39" x 52") - which would use 12 D9P blocks or 108 5" squares.

If you wanted to add borders to make it a different size, you can. You can also make the center less - say 2 x 3 (or 26" x 39", 6 D9P blocks or 54 5" squares) and add borders to get to your desired size.

Thanks. Now to figure out which fabrics to use :)

This chart was posted on here a few days ago about D0P sizes & it may be helpful to you (& others!)

http://www.quiltingboard.com/t-150081-1.htm