When I was a beginner quilter, I struggled with sewing an accurate quarter-inch seam allowance. I tried all the tricks, but my quilt block piecing was all over the place. It was super frustrating. My seam allowances were too big, so I cut my fabrics a tiny bit wider to compensate. That was equally disastrous.
Picture your favourite infomercial “before” hands thrown up in the air, eye-rolling reaction.
How did I finally get perfect, consistent, quarter-inch seam allowances for accurate piecing, perfect points, and beautiful quilt blocks?
Game Changer #1: The Flanged Quarter-Inch Presser Foot
Behold, my secret weapon in the Quest for the Consistent Seam Allowance!
Unlike some quarter-inch presser feet, it doesn’t merely give you a visual for 1/4″ from your sewing machine needle. It also has a little black guide or flange. You run the edge of your fabric right against the flange as you sew. If your sewing machine didn’t come with one, definitely see if you can pick one up. My Janome “patchwork foot” was about $20 and it made such an enormous impact in the accuracy of my piecing!
Go order one now. I’ll wait.
Game Changer #2: Measure Needle Distance
When I bought my flanged 1/4″ foot, I was told that of course it would work for my machine. I got home and popped it on, and measured the distance from the needle to the flange.
I measured by placing a quilting ruler under the presser foot, right against the flange. I then slowly turned the hand wheel to lower the needle until it was close enough to the ruler for me to see if it needed adjusting.
Guess what? It was actually a bit more than 1/4″. I had to adjust my needle a smidge to the right to get it accurate.
My sewing machine is an old mechanical machine, and I put it in straight stitch mode when I’m sewing patchwork. That meant I needed to turn a hidden screw to move the entire needle bar a bit to the right. My best advice, if you’re not sure how to get it spot on for your machine, is to take it to your sewing machine to your repair person and have them adjust it for you.
Game Changer #3: Measure Pressed Patchwork
If you’re not pressing your seams carefully, you might be losing a bit of fabric in the fold.
While your seam allowance might be a perfect 1/4″ from the stitch to the edge, losing a bit on the right side of your patchwork can also cause problems with accuracy.
Here’s an experiment you can do:
Carefully cut 6 2″ squares of fabric.
Sew 3 squares together with your perfect 1/4″ seam allowance, then press the seam allowances to the side
Sew the other 3 squares together; press this set open.
Measure the finished result of both. If they’re not 5″, but your seam allowances are 1/4″, can you change your pressing technique to keep things accurate?
Game Changer #4: Press & Starch Before You Cut
I’m not a pre-washer of quilting fabric. No amount of evangelizing will change my mind on this. But when accuracy counts in my patchwork, I will always starch and press my fabric before I cut.
Not only does starch avoid distortion when you’re sewing on the bias, the act of spraying and then pressing your fabric also does a bit of pre-shrinking for you. I’ve done it the other way around, cutting before I starched, and there was a noticeable amount of shrinkage after pressing. 1/16″ to 1/8″, which will definitely add up!
Sewing Science Homework
What do you think? Give these 4 tips a try and see if your patchwork precision improves! Let me know how it goes in the comments. Happy stitching!
Why do you feel is not necessary to pre wash fabrics? Is it because of the sizing on fabrics keeps them stiffer and easier to work with? How then does shrinkage after the first wash affect your work? Do you find you get more”crinkling”? Or do you leave the first washing up to the client/quilt user?
I don’t mind the crinkle for utility quilts. For show quilts/cover quilts, I prefer the unwashed look. Mostly I don’t like the hassle and delay of having to wash, dry, press, and refold.
Me either, I want to dive in cutting and sewing right away!
And, I WANT the crinkle look after my quilts are washed.
I didn’t wash the fabric before making a quilt for a grandbaby. The first time it was washed, some of the dye bled on some other block. It was a mess, that never looked right, no matter what I tried to get it out. So I always prewash. The fabric goes in the laundry room as soon as I bring it home. I’ve never had a problem since.
Thank you Bobbie. Your email came as I was, again, struggling with my 1/4 inch chain piecing. You reminded me I have a new 1/4 inch foot (the one I got years ago was NOT 1/4 inch) and I put it on. SUCCESS! I’ve been sewing like a champ for a couple hours and it has been great. Thank you, thank you, thank you for the reminder.
Wendy that’s wonderful!
I also don’t pre wash my fabric. The sizing isn’t enough to make the cutting accurate so I too use spray starch. I like it when I finish my quilt and I give it that first wash, the fabric shrinks just a bit and I get a cozy finish.
Here’s exactly why I don’t prewash my fabrics: I feel the sizing is a gift from the designer and keeps my stitching accurate. The recipient will wash the quilt eventually and love the feel of a gentler softer gift. You do YOU and I’ll do ME. I will not be bullied.
I’ve heard it also depends on where you get your fabric. If from a quilting shop, no washing necessary…unless it’s mixed with fabrics from other places. The quality is better and they will also shrink at the same rate. If mixed, they will shrink different…causing a problem. I wash fabrics from Hobby Lobby, but not from our local quilt shop…I’ve never had them shrink from there. I usually get other fabrics when I’m making girls dresses. YES, they do shrink from other places, I ALWAYS wash them first. I starch also.
Totally agree! Garment fabric always gets pre washed! As for poor quality fabrics, I learned that lesson on my first quilt. Never again!
Hi! I’ve tried all these techniques to improve my 1/4″ seam allowances as well. And they definitely have helped. Currently I’m using a piece of marked painter’s tape. The best helper is time and practice. 🙂 And I’m with you on pre-washing, and I like the sizing in the unwashed fabric so I just iron. I’m sure I should – if only to be sure my fabrics won’t fade… but I never take the time to wash, too much extra time and work. Of course, I’m not quilting for show – just fun.
I only wash red or black fabrics. I found that newer fabrics do not ususally run/shrink like they did in the old days.
The beginners quilt class I took several years ago had a different solution to the 1/4″ seam allowance issue. Purchase a package of felt with adhesive on the back which is usually green and found in the hardware section of the store. Cut a small strip of the felt about a 1/4″ wide and 1 to 2 inches long. Place the ruler under your sewing foot at the correct distance and stick the cut strip alongside the ruler. When you are stitching your seams use the felt as a guide, keeping the fabric edge up against the felt. This method has worked well for me ever since I started quilting.
I always prewash my fabrics. I used to work in a fabric shop and you would be amazed at the dust and dirt in the corners of those places. Also some fabric bolts end up on the floor or stored in a dirty corner somewhere and you don’t want to make a quilt and give it away as a gift with all that hidden dust and dirt. If you take it out of the dryer promptly there is minimal wrinkles and since we press and starch anyway, it’s just so much better to start with clean fabric…..
If I’m gifting, I will always wash before I gift. My sewing room isn’t much better than the fabric shop!
Quarter inch or scant quarter inch?
That depends on your results from tip #3. If you’re losing some to turn of fabric, the scant quarter inch compensates.
Thanks for these tips Bobbie! I’ll be getting a flanged 1/4” presser foot tomorrow! I’m looking forward to piecing with it. I plan to measure the needle distance for accuracy too. I too am anti-prewashing.
I agree with the needle position adjustment. I have been quilting for a number of years and found that tip to work beautifully. I usually pre-wash and now I also starch when pressing before slicing and dicing! Thank you for your helpful advice. Curved seams are fine and look so soft and graceful.
Thank you for these great tips! I look forward to trying them all. I have not tried curved seams and would love to try.
Thanks for the great tips. I have a 1/4 inch foot so I will check its accuracy tonight.
I’ll always wash my fabric because you don’t know what’s crawled on it in a warehouse or who’s touched it when they haven’t washed their hands after sneezing/coughing/toileting/etc. Not to mention I’m allergic to corn and most starches out there contain corn starch.
When it’s still damp I double starch it (because I’m using a sizing that doesn’t contain corn) and iron it, then it’s ready to start my project.
Thanks Bobbie for these tips! You have wonderful insight into things that can literally drive us nuts, lol!
You’re so very welcome!
Believe thread weight makes a difference when piecing then pressing seams affecting final measurement.
Yes, very true!
Love, love, love the tips! I have the flanged foot but was still off until I move the needle a couple clicks. I also like the pressing tip; so many things tell you to press one way or the other, I think your tips are going to be a game changer for me.
I wash fabric because of my allergies. I want to starch but I have trouble with iron getting bl as ckspots on it which are hard to clean and then of course it comes off on fabric. Struggling with that. Quater inch foot works great but correct careful pressing is key! I do get better results with pressing open and then using my tailor Clapper to set. I know many disagree with open seams but I quilt mostly traditional and with seams pressed to side, it is less easy to free motion quilt. Better luck with pressed open seams. I say do what works for you!
Wow, so easy to measure the 1/4 inch with ruler. Mine was off too. My small piecing machine needle is stationary but I marked with a long line and voila! Thanks so much
I have more than one quarter inch foot for my machines. Each one has required the needle being moved to get an accurate 1/4 “. I use 1/4. ” graph paper to check needle placement.
I’m new at all this and I’ve heard that it depends on the batting you use. Polyester won’t shrink as much as cotton batting wil. If you use straight cotton for batting then using your unwashed material has a better chance of shrinking evenly when your quilt is washed. Is this right or wrong.
Every batting and fabric will behave a bit differently. Shrinkage depends a lot on how you wash it, how densely it’s quilted, etc, but any quilt made with cotton batting will definitely get nice and crinkly after washing.
That’s all separate from getting accurate piecing, which is the focus of this article.
I purchased the same foot for my machine but find it difficult to see when stitching as everything is too shiny with the machine light. So I use tape as well. Any suggestions?
Oh interesting! Do you have the same issue with other metal feet? I wonder if it’s just too shiny. Maybe you can get a matte nailpolish and paint that on to reduce the shine?
THANK you so very much for these tips! I was so frustrated yesterday after struggling with another quilt block with disappearing points. After reading your post I made the next block by starching my fabric FIRST before cutting. I also took the time to measure what I thought was a 1/4″ seam on scrap fabric. What??? It was not 1/4″! What an eye-opener. Today I made my first 4 flying geese sets and they are PERFECT. There is actually enough fabric above the points to sew a real 1/4″ seam when I put the pieces together. You’ve made me a happy, happy, sewist!
Terry, I’m SO HAPPY for you!!!! Thanks for sharing
I think I need to check my seams. I use a flanged 1/4” foot but I have just sewn 120 1-1/2” squares together and the width and length came both came out too long.
The foot is about 5 years old and I’m wondering if the metal guide has been pushed out of place.
It’s possible! I’ve heard of that. Hopefully a needle position adjustment will compensate
I pre wash unless using precuts. Fabric is chemically heavy and dirty. We don’t know what it comes into contact with before we get it, factory, packing, shipping, storage etc. A lot of things that can fill our air and lungs with nasty.