This post is part of the Sewing Back-to-School series, 30 days of helpful sewing articles by guest bloggers. Feel free to check out the original Sewing Back-to-School post for schedule and previous posts!
Gwen is visiting today from the blog, Gwenny Penny. In the spirit of things back-to-school, how cute is this Pencil Pouch tutorial that she designed?!? The tute was also featured on Craft Gossip!! Visit Gwen’s blog for tons more fun tutorials!
Hi, everyone! My name is Gwen, and I blog over at Gwenny Penny. This is such a wonderful idea for a series, and I’m so flattered that Sara asked me to be a part of it. Today I’m going to talk about the importance of maintaining the proper seam allowance when sewing.
Let’s start at the very beginning… What does seam allowance mean? Seam allowance refers to the area between your stitching and the raw edge of your fabric.
Seam allowance varies from pattern to pattern, so make sure you read through all of your pattern instructions first before you begin sewing. Many commercial patterns use a 5/8″ seam allowance. Quilt patterns use a 1/4″ seam allowance. Some patterns and tutorials may call for a 3/8″ or 1/2″ seam allowance, that’s why it’s so important to check first. Even though the differences between these fractions may seem small, it actually makes a big difference.
For example, if a quilt pattern calls for a 1/4″ seam allowance, and you use a 3/8″ seam allowance, you’ll lose 1/4″ on every seam, which can make a big difference in the overall size of your finished quilt. The reason you lose 1/4″, even though the difference between 1/4″ and 3/8″ is only 1/8″, is because you are actually losing 1/8″ from each piece of fabric! And those lost quarter inches add up quickly.
The diagram above really illustrates what a big difference variations in seam allowance can make. Now imagine an entire patchwork quilt that was supposed to be pieced with a 1/4″ seam allowance but was pieced with a 3/8″ seam allowance. A baby quilt could end up being more than 2″ narrower than it is supposed to be. A larger quilt could end up being 5 or 6″ off. It really does make a difference!
And that’s simple patchwork. What if you are sewing a shirt, and you use a different seam allowance than what the pattern calls for? If you use a smaller seam allowance, your shirt will be too big. If you use a larger seam allowance, your shirt will be too small.
It is also important to be consistent with your seam allowance. If your pattern calls for a 3/8″ seam allowance, you must use a 3/8″ seam allowance when sewing every single seam, unless the pattern calls for a change. For example, you can’t use a 1/4″ seam allowance for one part of a quilt square and then a 3/8″ seam allowance for another part. Your seams will not line up, and if you are working with triangles, your points may end up cut off or hanging out in space (Check out this video). If each seam is off a little bit, you’ll struggle with getting everything to line up, and we all know how much fun that is 🙂
So how do you make sure that you are maintaining the proper seam allowance throughout your project? There are several ways:
- When your needle is in the center position, your standard presser foot will not give you a 1/4″ seam allowance when you align the edge of the foot with the edge of the fabric. Many beginning quilters are shocked to hear this. But you can buy a 1/4″ piecing foot (which I highly recommend :). Measure your standard presser foot to find out exactly how wide it is from the needle to the edge of the presser foot. Most are a little less than 3/8″.
- If you can adjust the needle position on your machine, you can play around with it and measure to the edge of your presser foot to get the proper seam allowance. Make sure you write down which setting and presser foot you used to achieve that seam allowance so you don’t have to go through the same thing with your next project.
- There are lots of ways to create a seam guide on your machine. Use tape, a rubber band, a
small stack of Post-It notes, etc. Just measure the distance from your needle to where you need to place your seam guide to achieve the proper seam allowance.
If you have any questions, please feel free to email me. And, of course, you are welcome to stop by my blog anytime. Sara, thank you so much for this wonderful series and for asking me to be a part of it!
Thanks again for having me today, Sara 🙂
Rubber bands! That’s such a good idea. I usually use painters tape, but I’m going to try a rubber band next time. And I didn’t know that about the presser feet not being 1/4″. (I’m not a quilter, so I guess it doesn’t matter quite as much!)
The rubber bands are perfect! I will try it when quilting my borders!
Thank you for your great tips!
Thanks for this! This is something I struggle with. Mostly, it’s a matter of not taking the time to be super accurate. I tend to speed through things. And if you’re going to carefully maintain a seam allowance, you can’t really do that. I also thought my presser foot was 1/4 inch! Gah! Thanks for that revelation!
Love the illustration of the 1/4 versus 3/8 inch seam! Great post 🙂
You are the best Gwen!
Okay, this explains SO much why I’ve not had great quilting results… My seam allowances are consistent… but consistently WRONG! Oops. Thanks for the enlightenment, Gwen 🙂
Thanks so much for this seam allowance refresher Gwen! Great stuff!
Great tips Gwen! I tend to rush my sewing which usually means inconsistant seam allowances, I think I will try to be more patient and sew slower and pay closer attention 🙂
that is the best explanation of seam allowance I have ever seen..moving the needle over never occurred to me..thank you very much for this gift of knowledge…Bill ,a man who sews..