The Myth of The Quilting Holy Grail

We’ve all heard it a million times – keep a consistent quarter-inch seam when piecing quilt blocks.  That was the first quilting “rule” drilled into me as I started quilting nearly 30 years ago.  And at that time, it was really important for me to remember because I also sewed my children’s clothes, and those seams were 5/8-inch seams.  Quilt seams, compared to those clothing seams, looked so small.  I had to be careful, too, because during those days of machine piecing, there were no quilter’s foot or any type of quarter-inch foot available.  You either eye-balled it or used a seam guide.

That quarter-inch seam appears to be one of the few Holy Grails of Quilting…


Except it isn’t.


So now that I’ve just blown a gasket in the quilting part of your brain, let’s look at this in detail.  Remember, this is our year of Quilting with Excellence.  A large component of this is paying close attention to the basics and that quarter-inch seam is truly one of the basics.  Let’s first begin with the sewing machine.


Even the most avid hand quilters and piecers usually have a sewing machine.  Most quilters I know have several.  I have five that take up residence in my quilt studio:  A Juki 2010Q, a Featherweight, Janome 7700, Juki 810, and Loretta the Long Arm (who really doesn’t enter into this conversation of the quarter-inch seam).  All of the machines are used for different purposes, but the Juki’s, the Featherweight, and the Janome are used primarily for piecing.  All but the Featherweight were designed with quilters in mind.  Each has a quarter-inch foot.  But you know what?  Each of their quarter-inch seams are a little different – even if it’s just by a thread or two.  That’s why most quilting instructors will tell you to start and finish a quilt top on the same machine – so your blocks will remain a consistent size.

So, what does a thread or two matter?  On one block, certainly not a great deal.  But if you carry that difference over the entire quilt top, it can add up to as much or more than a half-an-inch difference in your rows coming out even.  And that is frustrating beyond belief when you’re putting your top together.  Even a walking foot can’t ease in so much difference.

However, if you’re like me, I’m not always able to start and finish a quilt top on one machine.  Big Red, my Janome, is my primary piecing machine.  I love that machine.  But she is a big girl and highly computerized, so she doesn’t get out of the house much unless I’m going on a quilt retreat that lasts several days.  If I’m attending an all day Sit and Sew or a class, I take my Marilyn (the Featherweight) or Jenni (my Juki 810).  Marilyn’s and Jenni’s quarter-inch seams are different from each other and different from Big Red’s.  I may begin a quilt on my Jenni and then finish it at home on Big Red.  How does one handle the seam difference?

Let’s consider the quarter-inch feet first.  These feet are also called quilting feet, although a better name for them would be piecing feet, since you don’t actually quilt with them.  Most sewing machines made with quilters in mind come with one of these feet.  This is the foot that came with Big Red.



It has a phalange on the right side.  If the fabric is lined up touching the side of the phalange, and the needle is in the center position, I should get a quarter-inch seam.



Which I do.  The blue tape in the right-hand side of the ruler is at the half-inch mark.  When I press the seam open to check to make sure I have a half-an-inch seam allowance, it measures correctly (1/4 + 1/4 = 1/2).

There is also a seam called the “scant quarter-inch.” This simply means that the seam allowance is actually a thread or two less than an entire quarter-inch.  Some quilt patterns call for this seam allowance and there is a foot made for this.  The Little Foot Quilt Shoppe ( makes this scant quarter-inch foot for all makes of machines, including Featherweights!

If you check out the seam below that has been sewn with the Little Foot on Big Red and then pressed open, you can see that it’s just shy of that exact half-inch mark.  It is a true scant quarter-inch.



All of this leads me to one conclusion:  That if I sew either a true or a scant quarter-inch seam on my Janome 7700, it is a true or scant quarter-inch.  But like I said earlier, I don’t always start and finish a quilt on Big Red.  So, what’s a girl to do?


There is a “test” you can run – and should run – on each of the sewing machines you piece with.  First, rotary cut three strips of fabric.  Two of these strips should be of the same color and the third of a contrasting color.  Make sure they measure 2-inches by 7-inches, they are of the same type of fabric, and they are cut on the crosswise grain.


Sew the three strips together, using what is deemed by your sewing machine as the quarter-inch foot, with the contrasting strip in the middle.  Press the seams to the darker fabric.  Now measure the strip.  It should measure exactly five inches in width.


The middle strip should measure 1 ½-inch across.


If the middle strip is wider, then your seams are a bit less than a quarter-inch.  If the middle strip is narrower than 1 ½-inches, then the seam allowance is more than a quarter-inch.

I ran into this problem on Jenni – my little Juki that I take to class and day-long sew-ins. Her quarter-inch foot’s seam is several threads larger than a true quarter-inch.  I would have run into serious trouble switching a quilt top from her over to Big Red.  The first thing I had to do was figure out exactly how much I needed to adjust Jenni to get that exact quarter inch.  There are several different ways to do this, but the easiest and most convenient way I’ve found to deal with this problem is a notion called Perfect Piecing Seam Guide by Perkins Dry Goods in Bloomington, MN (  This little notion is also sold in many quilt shops.


I’m not sure if you can see it clearly or not, but on the rim of this small, yellow ruler there is a tiny hole.  I put a piece of green fabric under the ruler, hoping it would make it more visible.

Raise the presser foot up on your machine and position the tiny hole so that your needle can go directly through it.  Please do all of this manually.  Do not try to do this by depressing your foot pedal or using the sew button on your machine.  You will break a needle.  When the needle can go cleanly through the hole, lower your presser foot to keep the ruler firmly in place on your machine.  The right side of the Perfect Piecing Seam Guide is exactly where the edge of your fabric will need to go in order to get a perfect quarter-inch seam.


At this point, you can either mark this location with a permanent marker or use something like a strip of moleskin to use as the fabric guide.  Whaaaala….perfect quarter-inch seams.  I use this method on Jenni and I have had no trouble transferring anything over to Big Red and keeping consistent quarter-inch seam allowances and block size.

Now I know what some of you are saying…”I have the option of changing needle positions on my sewing machine.  Isn’t this just easier?”

Big Red has that option, too, and I’ve used it sometimes.


And this is a viable choice, just remember to do two things.  First, do the strip test to make sure you’re getting an accurate quarter-inch seam allowance and second, if you have to change your needle plate position when you move your needle, be sure to remember to change it back to the normal factory setting or you’ll break a needle, which can play with your machine’s timing…which is never a good thing.

Now all of this brings me back to when I blew the quilting gasket in your brain as I told you the quarter-inch seam is not the Holy Grail of Quilting. 

While it is important to keep a consistent seam allowance, what’s even more important than this is making sure your blocks all come out the same unfinished size called for in the pattern.  And while I grant you that most of the time a quarter-inch or scant quarter-inch will be adequate in this construction, it’s not always true.  That’s why it is oh-so important to make a test block of any pattern before starting on the actual quilt.  If the test block comes out exact using the standard seam allowance, you’re good to go.  If it doesn’t, there are a few things you can do:

  1. Check your foot.  My Little Foot looks amazingly like one of my applique feet.  I can’t tell you how many times I’ve grabbed the applique foot thinking I had my Little Foot.
  2. Did your foot “bobble”? Sometimes feet aren’t attached securely, or they tend to wiggle a bit.  Make sure you’re feeding the fabric through the machine slowly and steadily.  For as long as I have been quilting and teaching quilting, I do not think anyone can sew an accurate seam at full-throttle.  Remember, it’s not a race.  Slow and steady makes for much more accurate piecing (and way less ripping out).
  3. Check your thread. As odd as this may sound, if your seam allowance is off just a tad and you’re sure of your accuracy, the thread may be the culprit.  If the seam allowance is just a bit too narrow, go with a finer thread.  If it’s just a thread or two too wide, try a thicker thread.  Re-test and see if this works.
  4. If none of the above work, you may need to significantly alter your seam allowance until the block comes out exactly the unfinished size that the pattern calls for. Don’t be afraid to do this.  Remember, the ¼-inch seam allowance rule can be broken.


Again…standard disclaimer….I do not work for the Little Foot Company or Perkins Dry Goods nor do they underwrite any portion of my website.  I recommend them in this blog because I’ve used their products and found them consistently stellar with their products and their customer service.


And an update on my heating situation, since I’ve gotten emails and messages…I finally got heat today.  There still are a couple of more repairs to go on the unit, but the thermostat now registers a wonderfully warm 72 degrees.


Until next week…Quilt with Excellence!


Love and Stitches,

Sherri and Sam


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