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CindyinNY 03-19-2011 07:47 PM

I am having a really hard time with block sizes.
I want to make 9 squares that will make a finished block of 12 inches. Sooooooo to practice, I cut out some scraps at 5 inches thinking that would make 4 inch blocks. Just to be on the safe side I asked dh if it would work..........NOPE!

Is there a chart here or somewhere that tells what size to cut to get the size you want?
I did a search here but all I found was this one http://www.thequiltedsnail.com/scale.html and it was of no help at all! May as well be written in Greek. :lol:

charmpacksplus 03-19-2011 07:53 PM

You need 4.5 inch squares to make a nine-patch that finishes up at 12 inches. Formula is 12 divided by 3 = 4, plus 1/2 inch for seam allowance. Unfinished, your block will be 12.5 inches.

MTS 03-19-2011 07:55 PM

So you want to make a 9 patch block that will finish at 12", right?

So since the 9 patch is a 3x3 layout, you need each block to finish at 4", which means you need to cut them 4.5" square. You only add .5" to the finished size (two 1/4" seam allowances).

Make sense?

milp04 03-19-2011 07:56 PM

Hi Cindy,

OK. You want your finished block to be 12 inch.

You want the block pattern to be a 9 patch block.
That's 3 rows of 3 blocks, so each block is 4 inch finished.
So 1 row, 3 blocks, 4 inch each block, 3 x 4 = 12 inch finished

For each section or square of the block you need to add
your seam allowance to all sides, which is generally 1/4 inch.

So your 4 inch finished square is 4 1/2 square to start.

So for whatever size block finished you have, then add 1/4 inch seam allowance at each seam.

It sometimes helps to sit with a piece of paper and draw it out then add the measurements and add the seam allowances at the seams.

Hope this helps.

Pam M

CindyinNY 03-19-2011 07:58 PM

Yes, thank you. I had my dh help me figure that out. I really would like to have a chart to refer to in the future though. Maybe it doesn't exist. lol

candi 03-19-2011 07:59 PM

Cindy, the link you posted is for enlarging/reducing patterns on a copier, not cut sizes, that is why it confused you.

So you are trying to make a nine-patch square that finishes at 12"? Is so, you cut the squares at 4.5". Every time you join the seams with a quarter of an inch seam, you loose a total of half and inch, so 4.5 times 3, you loose and inch and half. Note that your actual block will measure 12.5", but once you join it to other blocks or bind, it'll finish at 12. Hope that didn't confuse you :)

Edited to add: wow see you already got multiple responses, I guess I took my time, lol.


Originally Posted by CindyinNY
I am having a really hard time with block sizes.
I want to make 9 squares that will make a finished block of 12 inches. Sooooooo to practice, I cut out some scraps at 5 inches thinking that would make 4 inch blocks. Just to be on the safe side I asked dh if it would work..........NOPE!

Is there a chart here or somewhere that tells what size to cut to get the size you want?
I did a search here but all I found was this one http://www.thequiltedsnail.com/scale.html and it was of no help at all! May as well be written in Greek. :lol:


MTS 03-19-2011 08:05 PM


Originally Posted by CindyinNY
Yes, thank you. I had my dh help me figure that out. I really would like to have a chart to refer to in the future though. Maybe it doesn't exist. lol

But every block is different. Suppose you were making a Churn Dash - the math on that is a bit different because the layout of the block is different (4x4).

The basic premise is you take your finished size block, break it down to your finished size components, and then add 1/2" to each of those measurements. Or do it in the reverse. That will work for squares.

Really, I've got to say though, that there are some basics that at some point you really just have to learn.

Here's a book by Joen Wolfrom
http://www.amazon.com/Make-Any-Block...0593740&sr=1-1
You can pick up a used copy for $6. Maybe that will offer you some sort of guidance.

CindyinNY 03-19-2011 08:16 PM

"Really, I've got to say though, that there are some basics that at some point you really just have to learn."

Ohhhhhh I AM learning! :lol:

I think I have it now. Cut blocks 1/2 in. bigger than what I need,for this one anyway.
Thanks for the book suggestion, I just wish I had the $'s to buy all the books sugested to me. I am keeping a list though just incase my ship ever does comes in. I think my ship was the Titanic though. :lol:

Scissor Queen 03-19-2011 09:09 PM


Originally Posted by CindyinNY
I am having a really hard time with block sizes.
I want to make 9 squares that will make a finished block of 12 inches. Sooooooo to practice, I cut out some scraps at 5 inches thinking that would make 4 inch blocks. Just to be on the safe side I asked dh if it would work..........NOPE!

Is there a chart here or somewhere that tells what size to cut to get the size you want?
I did a search here but all I found was this one http://www.thequiltedsnail.com/scale.html and it was of no help at all! May as well be written in Greek. :lol:

The simplest way to keep from doing the math and having your blocks come out the right size is go get yourself a 12.5 inch ruler and paper big enough to draw full blocks on. Use the ruler to make a square and then draw your seam lines in the block. Measure your parts and add seam allowances. Don't forget the outside pieces already have a seam allowance on one side. To simplify things, for half square triangles add a full inch and then square them up.

You can get plain newsprint in Wal-Mart in the aisle where they sell boxes and tape.

Painiacs 03-19-2011 10:20 PM

Glad to know I'm not the only math challenged quilter!!


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