Quarter-Inch Game Changers!

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.

To get an accurate quarter inch seam allowance, measure the distance from your sewing machine needle to the edge of your patchwork presser foot. - geeky bobbin

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!

20 thoughts on “Quarter-Inch Game Changers!

  1. 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?

    1. 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.

    2. 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.

    3. 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.

  2. 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.

    1. Totally agree! Garment fabric always gets pre washed! As for poor quality fabrics, I learned that lesson on my first quilt. Never again!

  3. 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.

    1. I only wash red or black fabrics. I found that newer fabrics do not ususally run/shrink like they did in the old days.

  4. 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…..

    1. If I’m gifting, I will always wash before I gift. My sewing room isn’t much better than the fabric shop!

    1. That depends on your results from tip #3. If you’re losing some to turn of fabric, the scant quarter inch compensates.

  5. 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.

  6. 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.

  7. Thank you for these great tips! I look forward to trying them all. I have not tried curved seams and would love to try.

  8. Thanks for the great tips. I have a 1/4 inch foot so I will check its accuracy tonight.

  9. 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.

  10. Thanks Bobbie for these tips! You have wonderful insight into things that can literally drive us nuts, lol!

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