Basics Tutorial : Sewing Accurate 1/4" Seams
While a lot of quilts can be made without using an accurate 1/4″ seam, if you are following a pattern, best results come with accurate seams. Today I’m sharing a good method for finding accuracy for you and your machine!
My best example of a inaccurate 1/4″ seam is this block –
I love this block, but that tiny white strip was not in my original plans. I did all the math, worked out all the details for a perfect 12 1/2″ x 18 1/2″ block, just before adding the last row – I measured. Thank goodness! I then calculated the needed piece, added it, and vowed to get my 1/4″ seam accurate!
Here’s what I’ve learned, and how you can achieve an accurate 1/4″ seam.
These are the sewing machine feet I’m using, a 1/4″ foot, and a standard foot with a wide needle opening.
Cut a few strip sets, at 2 1/2″ wide, mine are 5″ long.
Verify that your foot is attached tightly, or it may be wobbly.
Put your fabrics under and sew. My fabrics are lined up and butted against the rail on the side of the foot.
Now set your seam and press. Yes, I like to press open, and in this case it lays nice and flat for the next step.
Measure your set. It should measure 4 1/2″ exactly.
See how that little bit could add up in a block, like my example?
Let’s make a small adjustment, and try again. These are my standard settings, when I turn on my machine –
Here’s the adjustment – move the needle .5 mm to the right –
Sew another strip set, set and press the seam, now to measure!
Exactly 4 1/2″, and the seam is at 2 1/4″ – an accurate seam!! Here’s a closer look –
But I know that not everyone has that nifty little foot – so let’s look at the regular foot. Grab your ruler and masking tape, and set down with your machine.
Put your needle down and measure 1/4″ away.
Gently lay down a piece of tape, 1/4″ away from the needle.
See the problem here? It’s covering the feeddog – not a good thing. You always want your fabrics to feed evenly through the machine, and they may get sticky if you piece a lot. My foot has lots of room for the needle to move, so that’s what I’m going to do!
ETA: You could test this placement, then when accurate, mark it on your bobbin cover with a permanent marker. Especially helpful if your needle doesn’t move in so many increments like mine.
I moved the needle to the right 2.0 mm – I’m just guessing here, it’s all about trial and error with your machine!
Put your needle down again to measure and mark your 1/4″ with tape.
Notice that the tape seems to line up with the edge of my foot!? Sew a strip set together, set and press your seam to measure it.
It’s really close again, but not exactly 4 1/2″. One minor adjustment should be all that is needed! I moved my needle to the right just .5 mm once again.
Sew, set and press a strip set, and then measure, again. Success!
Looking at it slightly closer again, it measures 4 1/2″ and the seam is at 2 1/4″ – accuracy!
I realize that not everyone has as nice of a sewing machine as I do, you can make this work for your machine, learn about the different needle positions and feet. There’s a good combination for the two of you too! It took me about 10-15 minutes to work out both of these methods for my machine, a little time well spent, and full of rewards as you piece your next project.
**I should say that the middle of a project is not the right time to change your methods – consistency for this project is good, and accuracy for the next one is great!
I hope that this is helpful! Anyone have anything else to add? Questions? I’ll answer them in the comments for everyone :)