Why doesn't my math add up?

[ericksonmelanie]

I am working on the Twist & Shout quilt. The first step in making a block is to sew three 2.5" strips together lengthwise and then cut them into 4.5" x 6.5" pieces. No matter how many times I have sewn the strips together, I can never get to the magical 6.5" wide required. I have measured my needle placement to make sure I am getting a 1/4" seam. I have tried shorting the seam. I am quite flummoxed. I ran into this same problem when I put together a Keyhole Quilt. For both quilts, I used 2.5" precuts. Any suggestions on how to get to 6.5"?

[Caroline T.]

Several things I can think of for you to check.

1. Measure the width of the strips, it could be they aren't true to size (not uncommon), also if the edges are pinked you need to understand some manufactures consider 2.5 inches from the valley (of the pink) and others consider 2.5 inches from the peaks.

2. Thread thickness can have an effect on your finished product. If your thread is thick, when you press your seams the thread can cause a difference in your finished width, if this is the case, you should move your needle over a bit to compensate (this is referred as sewing a "scant 1/4 inch seam" )

[Rhonda K]

Check the measurements of each strip after it is sewn.

Left one should measure 2 1/4 inches, Center strip should measure 2 inches, and Right strip again at 2 1/4 inches.

Check your pressing methods to make sure there isn't fabric left in the seam line (a wrinkle).

[KPH]

Welcome to the forum!

I can't think of anything to add to answer your questions. The replies you've already gotten are excellent!

[Caroline T.]

I'm so sorry, I just noticed you are a new member to the forum, welcome. We're practically neighbors. I'm in Puyallup, and there's a few others in the area too.

There's a Sew, Craft, quilt expo next month @ the Puyallup Fairgrounds. If you've never been, you might want to check it out.

[bubba]

And me....I'm in Tacoma!!

If you have three 2.5" strips and you are sewing them with 1/4" seams, in my head they turn out to be 7" (2.5 plus 2.5 plus 2.5 equals 7.5, minus .25 and .25 (half inch) would take it down to seven.

[GuitarGramma]

And me....I'm in Tacoma!!

If you have three 2.5" strips and you are sewing them with 1/4" seams, in my head they turn out to be 7" (2.5 plus 2.5 plus 2.5 equals 7.5, minus .25 and .25 (half inch) would take it down to seven.

Pat, you correctly subtracted the 1/4 inch from the two outside strips, but the inside strip loses 1/2 inch (1/4 inch on each side).

So add the three strips (2.5+2.5+2.5=7.5)
Then subtract the 1/4" from the leftmost strip, 1/4" from the rightmost strip, and 1/2" from the center (-.25-.25-.5=1.0")
7.5" - 1.0" = 6.5"
Voila!

Welcome, Melanie. And I concur with earlier posters: double check the width of the strips you have, and move your needle a bit more to the right so that you're sewing a bit less than 1/4" seam. When your fabric folds over your thread, you lose a little bit of fabric and your seam actually acts as if it's MORE than 1/4".

One more trick: Set your seams before ironing the pieces open. When someone finally told me to do that, it made a world of difference in my accuracy. "Setting a seam" means that you sew your two pieces of fabric together and iron the seam while your fabric is still "right side to right side." Then, and only then, open the fabric and iron/press. The heat on the newly sewn seam relaxes the thread and makes it kind of sink into the fabric. You end up with a more accurate 1/4" seam.

[bubba]

Pat, you correctly subtracted the 1/4 inch from the two outside strips, but the inside strip loses 1/2 inch (1/4 inch on each side).

Ooppppppsssss!!

[Star lover]

You’ve gotten some fantastic advice, so I have nothing else to add........except to welcome you to the forum from Michigan! So happy you’ve joined us!

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[Bubby]

Welcome to the forum from Missouri.