Friday, September 28, 2012

Add Seam Allowance {when you don't have a pattern or your pattern doesn't have it}

How to add seam allowance to a sewing project if you don't have a pattern or the pattern doesn't have it
I have never sewn from a pre-made pattern before. I don't know whether I'm just stubborn, intrigued by a challenge, or lazy (maybe a bit of all 3) but I've always just tried to envision how something would fit together, and then make it.

In one of my sewing escapades, I created a pattern for something but realized I hadn't accounted for the seam allowance. Oops. If I had made it as-is, it would have ended up too small.

When joining two fabrics together, that important extra allowance of fabric (generally 1/2" all around), prevents your creation from falling apart at the seams. Literally. As well as preventing fraying from occurring right on the joining seam.

If you forget to add seam allowance and realize it after you've cut out your fabric? Move your breakables and tell your husband to exit quickly, because you'll want to punch something.

If you forget to add seam allowance to your pattern before you've cut out your fabric? No problem! Everybody's safe! I have an easy solution.

First let me tell you about my go-to cutting tools.

I love my Fiskars Rotary Cutting Set. It comes with a self-healing mat, rotary cutter and acrylic ruler. If you don't have these three things? Get them. I use them all. the. time.
Fiskars Rotary Cutting Set is essential for any seamstress and comes with a self-healing mat, rotary cutter, and acrylic ruler
The Acrylic ruler is what I use to add and cut my fabric with seam allowance when my pattern doesn't have it. It has little measurement lines that help you see exactly where 1/2 inch is, so you can add it easily before cutting. And it's the perfect straight edge.

Acrylic rulers help measure seam allowance and can be used as a precise straight edge

For something straight, it was simple to add 1/2" and simply cut with the acrylic ruler in place. The white paper is my pattern without seam allowance. With the ruler in place, I added 1/2" on each cutting point.

Place acrylic ruler on top of fabric, adding seam allowance of 1/2 inch to all sides

For adding seam allowance around a curve, you can use a regular ruler, or cloth measuring tape. At the 1/2" mark, go slowly around the curve, making marks directly on your fabric every so often to keep it even, with a disappearing ink pen (this photo is of me adding it to a pattern, but if you've already cut your pattern, write directly on your fabric).

*disappearing ink pens allow you to write on fabric and then blot off color with a damp cloth. They come in very handy!

Add seam allowance to a curve by using a ruler at 1/2 inch and mark spots with pencil

Don't fret if you made your own pattern or bought a pattern that doesn't have seam allowance! It's easy to fix BEFORE you cut...or husbands be warned. :)

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  1. Great advice. Now where can I find one of those disappearing ink pens? LOL


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