Welcome to the next post in the #QuiltLikeABoss series! After the last post by Sarah on cutting, today we will be talking about piecing. The vast majority of quilt designs will require you to piece your fabric, with the main exception being paper-piecing that Abby will talk about in a future post for the series.
The standard seam allowance for quilting is a quarter inch. There are some times where this is super super important and other times where this specific measurement is less important, which I will discuss below. I will also provide some tips for achieving an accurate 1/4″ seam allowance and for checking if your seam allowance is right.
The (Un)Importance of a 1/4″ Seam Allowance
As I mentioned, some quilt designs it is imperative that you sew with a 1/4″ seam allowance. If your design has pieces of different shapes or sizes, if you don’t sew an accurate seam allowance the pieces won’t fit together properly and you won’t be able to make the seams match and/or the quilt top sit flat.
However, for some designs the 1/4″ isn’t quite as important, consistency is more important. For example strip quilts or quilts made from squares all the same size, as long as you sew a consistent sized seam allowance it technically doesn’t matter what size the seam allowance is. HOWEVER be warned, if you use a different seam allowance in these cases your quilt will turn out a different size so you need to account for that (bigger seam allowances = smaller quilt).
Having said that though, I still recommend aiming for the 1/4″ seam allowance even if it doesn’t matter for your design as it’s good practice for any future projects you may make that do require the precise 1/4″.
What is a Scant 1/4″
If you’re reading information about piecing quilts you may come across the phrase a “scant 1/4 inch”. What this means is that your 1/4″ should be a tiny bit smaller than a 1/4″, so that when you account for the thread and the thickness of the fabric the finished pieces are exactly 1/4″ smaller than the cut pieces. I have drawn up this diagram to try and explain this:
So, when anything says to use a 1/4″ seam allowance, it’s best to use a scant 1/4″ for the best accuracy.
Tips for sewing a 1/4″ seam allowance
Before you start your actual quilt you should check your seam allowance. Even though I’ve made plenty of quilts I always do this at the beginning of a project just to double check.
First, get your machine set up with it’s 1/4″ foot (or if you don’t have one, try this method with a few feet to work out which is the best one to use). 1/4″ feet are designed for you to either line up your fabric with the edge of the foot, or to butt it up against the guide (the black metal in the below picture). If you don’t have a 1/4″ foot here are some alternatives to help you with the accurate seam allowance.
Then grab a piece of paper or thin card and un-thread the needle of your machine. On this piece of paper, grab a ruler (I have a great 1×12″ ruler that I use for this, but any imperial ruler will work) and carefully mark a (thin) line 1/4″ from the edge of the sheet with a mechanical pencil (or a fine pen would work).
Then put the piece of paper in the machine as if it were fabric, lining up the needle with the right hand edge of the line (so it’s just to the seam allowance side of the line). Check where this lines up with the foot and take a mental note. Then carefully sew along the line; as there is no thread in the machine it will just make a line of holes in the paper.
Next, remove the paper from the machine and examine where your holes are in relation to your drawn line, and also re-measure the distance from the middle of the holes to the edge of the paper; it should be 1/4″ or a tiny bit less (remember the paper side of the line is the 1/4″). If it’s not, repeat the process until you’re happy.
Tip: If the 1/4″ seam allowance isn’t quite right when using your foot as a guide, you may be able to move your needle slightly to account for it, as it’s easier to use the foot/guide if possible. This is what I do with my Janome in Australia, if I use the black guide with the 1/4″ foot I have my seam allowance is a little large, so I move the needle a tiny bit over to the right to account for this.
Once you’re happy with your measurement I suggest checking it without the drawn line; pick another side of the paper and sew another line of holes, this time without drawing the line first, and measure it. If the measurement is still accurate then you’re ready to move onto sewing fabric!
This may seem a lot of effort and you might want to skip it and get sewing right away, but it’s worth the few minutes now rather than messing up your quilt top because your seam allowances weren’t right.
Methods to check your accuracy
There are some pretty quick methods for checking the accuracy of your seam allowance using your fabric. I recommend spending a few minutes completing one of these exercises to get the feel of the seam allowance and check your accuracy before starting your quilt top. This tutorial by Pat Sloan takes you through the process well.
One Last Note on Quilt Piecing
The only other thing I want to note is about backstitching; generally you don’t backstitch at the beginning and end of your seams when making a quilt, as all the ends will be enclosed by another seam, either within the quilt top, or the binding.
As always, any questions please ask away in the comments!
Click here to go to the #QuiltLikeABoss page for links to all the posts in the QuiltAlong and other information!