A Scant Quarter Inch Seam

what is a scant quarter inch seam anyway?

What is a scant quarter inch seam anyway? Is there a quilter out there who didn’t ask the question? I’ve heard and read it is what you get when you sew not on the line but right next to it on the seam side. That is easy enough to do and logically that would make your seam less than a full 1/4″, but it doesn’t.

a scant 1/4″ seam recognizes thread takes up space

When you sew just to the seam side of the 1/4″ seam line placing your stitches within the seam allowance, you are giving the fabric room to wrap over the thread. That is what is known as a scant 1/4″ seam. The block will measure the correct finished size. When sewing directly on the seam line, you lose the thread width when you open and press the quilt block. It is such a minuscule amount, why be concerned over a thread width?” Remember, there are no quilt police. What it can mean is those sharp points in your blocks may not be so sharp!

sewing is like driving a car

I tell all my students who have little to no experience behind a sewing machine; sewing is like learning to drive a car. You shouldn’t be driving a vehicle faster than you feel you are in control. It does not matter how fast it goes if you lose control. Don’t try to sew faster than you can keep a consistent seam width. I assure them what is important is to find their comfortable speed and then we will focus on not weaving in your lane. When you can sew a consistent seam width then we will work toward a consistent scant 1/4″ seam.

Establishing guides for seams

Establishing guides for seam widths can be done in so many ways. I’m all for encouraging everyone to find what works for them. I’ve been sewing for more years than some of you have been alive, and I can’t be consistent all the time. My mind wanders and along with it so do my stitches.

A good starting point is to examine the plate under the pressure foot for line markings of distance from the needle. Frequently they are in 1/8″ increments. For quilting, the 1/4″ mark is the focal point. The idea is to stitch a thread width to the left. Yes, if you are sewing with a thicker thread, like a #12, you can adjust to go say 2 thread widths. Doing the following test will let you find the scant movement to have it perfect!

how to establish the scant 1/4″ seam

To establish the scant 1/4″ seam, you will need two strips of fabric accurately cut 1 1/4″ x 3″. You will be sewing the two fabric pieces together on the long edge by putting them one on top of the other and carefully matching all sides.

Before sewing the trial strips, extend the 1/4″ mark on the plate 3 or 4 inches in front of the needle with the painter’s tape. Placing several layers of the tape on top of each other may be easier to use as a guide. The tape is easy to move until that scant 1/4″ is found.

stitch a test piece

You will now stitch a test piece with the two fabric pieces already cut. With right sides together and all edges matching, align a long edge of the fabric pair against the painter’s tape edge and guide the fabric under the needle.

When completed, press open by lifting the top fabric and gently smoothing it away from you and gently pressing the seam with a dry iron. Now, measure the width of the two fabrics. What did you get? If you followed the tape guide and it is 1/4″ from the needle, your measurement should be exactly 2″. If it is more than 2″, your tape is too close to the needle; narrower means your seam is too wide. Adjust the tape until you get 2″ exactly. The tape will be in the exact place for a scant quarter inch seam since the perfect 2″ measurement has accounted for the thread width.

Machines with adjustable needle position

A sewing machine with adjustable needle position left or right may produce a scant 1/4″ by moving the needle in small increments. Using the same trial fabric dimensions, stitch following the 1/4″ line from the plate extended with tape, as above. Think it through to be sure you are going in the right direction.

Once you have mastered the test and you are getting 2″ as your measurement, don’t move your tape guide!

alternative guides

There are alternative guides to painter’s tape. I have tried several of them at one time or another. I finally found one that is my favorite. Keep in mind, all are designed to give you a guide to use while feeding the fabric under the needle.

Online, you can find strips (mine are purple) that are self-stick and 3-4″ long. I used these frequently with my students because I could wash them off with sanitizer wipes in between student use. Mole skin found with other Dr. Scholl products also do the job. The adherence is good if you don’t try moving it often. If your machine comes with a guide/screw attachment, this is an easy adjustable answer. Requirement is a pre-drilled screw hole right of the needle. If your machine has one, check with your dealer or sewing center to see if they carry them. They are inexpensive and are especially nice if you do garment sewing with 5/8″ seams and then want the 1/4″ seam for piecing.

One I have not tried and have only seen online, is a strong magnet that sits to the right of the needle. This magnet has an edge for you to guide the fabric edge along (just like painter’s tape). The magnetic guide is not recommended if you have a computerized sewing machine.

There is also a tape made that you line up with the needle and it gives 1/4″ lines on both sides. I don’t recall who made it, but I am sure if you visit online sites or stores selling notions you will find it.

In addition to looking online, check around at your local quilt shops and fabric stores along with sewing machine stores. You will be amazed at what is out there.

my favorite guide

This is my favorite guide. Sew Straight by Quilt in a Day – 735272030003 Quilting Notions. I really love it. In fact, I should buy a couple more! Eleanor Burns personally suggested it to me when we chatted at a Sew Expo. She was so easy to chat with one on one. I was a huge fan of Quilt in a Day and have several books she wrote, and patterns designed by her.

in conclusion

In conclusion, I do hope you will easily find your scant 1/4″ seam. Even with the Quilt in a Day Sew Straight, must remember the line for a scant 1/4″ is really to the left of the line. Lines have width, too!

Also see Before You Start Cutting for a refresher on accurate cuts. Accurate cuts and accurate seams make a quilter happy!