5 Steps to Improving Your Piecing Accuracy

Posted by on Feb 13, 2012 in Quilting | Comments

Greetings crafters! Amy Gibson here, of Stitchery Dickory Dock, and the Craftsy Block of the Month – a free year-long quilting series here on Craftsy!

5 Steps to Improving Your Piecing Accuracy

Quilters- trust me, I know, there is nothing more frustrating than cutting up your favorite fabrics and laboring over a ridiculously awesome quilt block, only to discover that it’s come out too small, or the pieces don’t fit together well. Ugh! Hate that! It happens to EVERY quilter at some point, but don’t despair- there are things we can do to prevent this frustrating experience. Join me in this post as offer 5 basic steps you can take to help improve your quilt piecing accuracy.

1. A Scant 1/4″ Seam Is a Quilters Secret Weapon!
The fact of the matter is, it’s more difficult to achieve a true 1/4″ seam than one might think. Very often, the 1/4″ markings on your sewing machine, or even your 1/4″ presser foot, can be noticeably off. Unfortunately, the only way to really make sure, is to stitch a 1/4″ seam following whatever markings you’ve been using, and measure it with a clear ruler. Is the seam right on 1/4″? Or is your stitching just a touch over?
Even using my ¼ piecing foot, I found that my seams were too big! See? In the seam on the right, I followed the edge of my presser foot, which resulted in a seam that was just on the outside of the 1/4″ marking.

5 Steps to Improving Your Piecing Accuracy

But what’s better than a seam that’s exactly 1/4″? A seam that’s a hair under a 1/4″ of course! This is a scant 1/4″ seam. In the seam on the left, I made sure I could not see my drawn line outside of the presser foot, but rather kept it just under the very edge of the foot. This small change will keep your seams just a couple of thread widths under 1/4″, and will account for not only the seam itself, but also the actual fold in the fabric when your press your seams under.

5 Steps to Improving Your Piecing Accuracy

It doesn’t seem like it would make much difference, but even this tiny amount can really add up over the course of a block, so get in the habit of stitching a scant seam, and your blocks will thank you.

2. Press Well
When you press your pieces open there are several things to keep in mind- make sure your iron is on the highest cotton setting, use steam, and be sure you are “pressing” and not “ironing”. By this I mean to only place your iron straight down on the fabric, and not move it back and forth like you would normally do when pressing garments or linens. Moving a hot steaming iron back and forth over your delicate quilt pieces will almost certainly stretch and distort them, regardless of if the edges are on grain or bias.

3. Starch Is Your Friend
I know, it seems like this would just go along with pressing, but I think it’s so important, it deserves a spot of it’s own! Heavy spray starching while you press is one of the absolute best ways to help keep your accuracy spot on. As the sweeties over at my darling local quilt shop say, “It makes your fabric BEHAVE!” I couldn’t agree more! Starch stiffens your fabrics to prevent distortion when you’re handling & pinning your pieces. It rinses right out in the wash, leaving your quilt soft & snuggly.
Don’t be fooled- there are many starches available on the market, and some are even advertised as specifically made for quilting (here’s where I sound like an advertisement, but trust me, it’s not!)- I but in my experience, nothing does the job quite like Faultless Heavy Spray Starch. Seams lay flatter, fabrics stay crisp throughout the piecing process, and it even has a lovely scent (that’s probably just me reminiscing about my Dad, always always heavily starching his shirts when I was a kid!).

5 Steps to Improving Your Piecing Accuracy

4. Use The Right Tools

5 Steps to Improving Your Piecing Accuracy

Sharp Things: Keep your rotary blades sharp, and change your needle often. It’s easy to get lax about this, and forget to change them out. If you make it a habit before each new quilt project, you’ll find it’s worth the extra expense! (that’s what big discount fabric store coupons are for!)

Rulers: Have a nice assortment of clear, non-slip rulers available. Even though it may seem unnecessary to have zillions of them, including a 12.5″ square, a 4.5″ square, a small rectangular, a 6″ X 24″, etc, it really can aid in accurate cutting and a more relaxing experience when you can grab the right sized ruler for the job, instead of strain your eyes to make sure you’re cutting on the right line on a ruler that’s too small or too large. I also love adding a product called Omnigrid “InvisiGrip” to the underside of all of my rulers, and have found it the most effective way to ensure a steady grip. It’s crystal clear plastic that works like a window cling on the back of your rulers- stays put, and has nearly eliminated that annoying slippage.

Mat: Do invest in a high-quality self-healing mat, but try not to get in the habit of using the markings on the mat for cutting. These can be helpful if you need to cut a really big piece, but for most things your rulers will provide much better accuracy (ie the ruler should be completely covering the part of the fabric that you are cutting & using, not the remaining fabric).

5. Be Familiar With Basic Quilt Math, & Don’t Be Afraid to Use it!
I hate math, I’ll admit. But quilting requires a TON of it, so I’ve long since surrendered to the fact that I need to be comfortable with it. This means understanding how pieces add up, to equal a total measurement on a block or quilt, and even calculating how much fabric you’ll need to purchase at the quilt shop, or how many strips to cut for your binding. Once you know the basic equations, your trusty calculator can do the hard part.

5 Steps to Improving Your Piecing Accuracy

Here are a few of the most basic formulas that I use nearly every day when I’m quilting:


  • The total width (or height) of a block or quilt = the width of each piece X the number of pieces, minus .5″ for each seam

(So for example, our Balkan Puzzle block from February- 3.5″ Half Square Triangles X 4 Units = 14″ – 3 seams at .5″ each = a 12.5″ block. This one really comes in handy if you want to stop and measure part way through a block to see if you’re close.)

  • Total inches needed for border = quilt width X 2 + quilt height X 2 + border width X 4




  • Total inches needed for binding = quilt width X 2 + quilt height X 2 + 24″ excess to join




  • Number of strips to cut for binding = total binding length (see previous equation) divided by 44″



Well, thanks so much for joining me for this little refresher post! I don’t know about you, but I can use a reminder of these things now and again, and surely we all love our quilts to look as crisp and precise as possible- it’s just more fun that way! Hope you’re enjoying following along with the BOM and I’ll see you March 1st with 2 new blocks!



  1. Jennifer Rewis says:

    Thanks for your excellent direction. My Feb blocks were sized well for trimming by paying close attention to piecing with scant 1/4″ seams.

  2. Lisa says:

    Thanks for the tips! I totally forgot about the SCANT 1/4″ seam in the Balkan puzzle, and I think that is why mine was off. DUH! I was so excited about sewing that I didn’t make a mental note of it. I’ll be sure to remember that for the Chunky Chevron, which I am hoping to get done today.

  3. Chelsea Bailey says:

    I’ve had some bad experiences using steam because it can cause stretching and distortion. I fixed this problem by making sure I use plenty of starch. LOVE starch!

  4. Geraldine Pritchard says:

    I had no idea about the spray starch. I even was given some as a gift a few Christmas ago and have never used it. Will now. Thanks again. Oh, and loved the piece on the 1/4″ seams.

  5. debbie williams says:

    thanks! I forget every quilt.

  6. Kathy Schwalbe says:

    I’ll be heading out to buy some starch today! Thanks for the tips, I’m sure they will help.

  7. Wonderful love the instructions

  8. Salli Rainwater says:

    Thank you this was helpful information. Looking forward to March blocks

  9. Trina says:

    Thanks; that was well worth the time to read … and helpful even for long time quilters.

  10. Deb says:

    After all the years of quilting classes that I have paid good money for I finally have found a place where I can get really good information. Thank you so much. I am looking forward to more information.

  11. Gil says:

    I would like to add a helpful tip for those of us with a computerized machine like my Elna Q5300. I have a “scant” 1/4″ foot, as described by Elna, which is not scant. I searched the internet for answers and I found only one but it works. My machine needle is autoset to 3.5width so my 1/4″ is NOT scant. If I change the autowidth to 4.0 or 4.5 my needle moves a tiny bit right and now my seam is 1/4″ (hooray!) once it’s pressed open. This works on Elna, Janome, and some other machines as well. Worth a try.
    Excellent tips on this article. I’m going to give starch a try. Have never used it as I’m a devotee to iron free clothing. :D

  12. donna says:

    as a fairly new quilter, i enjoyed your tips. they were also easy to understand, thanks.

  13. Maryellenmiller says:

    Thanks for the wonderful tips. Will copy the math solutions to keep in my purse. Again, thanks.

  14. Melody Norris says:

    I just finished 2 of the Feb quilt blocks. The first didn’t measure out to 12.5″. On the 2 block I did the scant 1/4 ” seam. It did come out better.

  15. Eileen Menke says:

    I will try all your tips and am sure next blocks will be better.

  16. Sandy Carey says:

    thanks… helps alot to know that there are peple who will help make the best loking quilts.

  17. Denise says:

    Thank you for your helpful hints. I am piecing a delectable mountains quilt, it is all triangles, very challenging for me. I am definitely adopting the scant 1/4″ seam allowance

  18. Heather Ferris says:

    Another important tip is to “square up” each unit that you piece together. This will help keep things accurate as well.

  19. Debra says:

    Always enjoy the extra instuctions. Are alway so helpful.

  20. Hidee Smith says:

    I think all of these are great tips but I would add one more… don’t cut too many layers of fabric at onc time. It really doesn’t save the time you think it will and pieces can come out wonky. .

  21. Jackson says:

    Very good advice. I consider myself an amateur quilter, and got started because I wanted a Civil War quilt for CW re-enacting, but, as a former shop teacher, found that I enjoyed watching how the patterns come together. My drafting experience, I guess. Using the 1/4″ shy measurement, I figured that out early on and it works. I think of it as allowing for the saw kerf when cutting lumber. I second the emotion on the starch, too. I mix my own and put it in a pop bottle with a sprinkler top, just as my grandmother did. It took me a long time to realize that the numbers on my cutting mat were causing problems–I wish I had known that sooner. I now own a nice assortment of plastic rulers. The hardest part for me to learn was to work the material from the right to left instead of the other way around, again, as we would when cutting lumber. I’m learning and learn something new every time I do another Civil War Soldier’s Cot Quilt! Nice article. Thank you.

    1. Missy says:

      Would love to know the recipe for making starch!

      1. Support says:

        It looks like there are some great pages online that have different proportions of Corn Starch and Water! I cannot attest to the quality of these, but I would do a quick google search and have fun experimenting!

      2. Debi says:

        If you buy the Argo brand cornstarch it gives you the recipe for mixing it either cold or by boiling it. I found that by boiling it and it still on the counter it spoiled rather quickly. I think it has to be refrigerated. Just recently I bought the liquid starch and havent tried it yet. I think it might work better.

  22. Stacy says:

    Thanks! I’m new to this so the tips and the math are very welcome! Esp the non-slip stuff, I def need to invest in some of that. Ruler slipping is 90% of my trouble :P

  23. Glenys says:

    Thanks for the info. Periodically my seams are not the same and now I know why. Also really never thought about spray starch.

  24. Boni says:

    I am working on a bargello quilt for my Granddaughter’s graduation. Wish I had known about the scant 1/4″ seams but it is turning out pretty nice. I will try your tip next time.

  25. Hilda Hoas says:

    This is fantastic information, I have been quilting for about 10yr. but I am a very impulsive quilter, start, cut, sew, get done as fast as possible…I need to slow down and be more accurate,

  26. Peggy Davis says:

    Thanks, Amy. I really appreciate your taking the time to post this. Can always use a little extra help.

  27. Barbara Cann says:

    Thanks!! This was really helpful!!!

  28. jean Whelan says:

    Thank you, – I love quilting and spend a lot of my days making quilts.

  29. Caroline Asher says:

    Thanks for all the good advice and for giving of your time for the block of the month. I really enjoy this.

  30. Kerrie Purcell says:

    I am fairly new to quilting, and have just finished my first quilt top that actually relied on correct measurements. Puzzled why my measurements were out. Having just tested my Janome’s 1/4 ” foot – and of course it is significantly wider than 1/4 – I now understand why ! I also did a lot of measuring using my cutting mat. Hopefully by taking note of your suggestions my next piece of work will be much more accurate. Thank you for a great site.

  31. Linda F. Goodman says:

    Thank you so much for the tips on 1/4 inch seams. I too have had trouble in the past with quilt blocks not measuring up to the right size. This was a great help.

  32. Jacqui Munson says:

    Thanks for all the great tips. I started the scant 1/4 inch a while back and what a difference it has made!

  33. Marj Daniel says:

    This is most helpful.

  34. Betty Jones. says:

    Thanks for all your help, have enjoyed the block of month and have made both of mine already and as you said following the direction and making a 1/4 inch seam is very important and sometimes very difficult for me to do but I am getting better.

  35. Anne Gostlin says:

    Thanks so much for the gift of your time, not to mention your expertise and obvious love of art of quilting. I am enjoying the BOM course very much. It gives me a reason to spend some time sewing each month and reasons are often hard to come by in this busy life. The 5 steps above are great reminders given in an encouraging manner. Well done! Thanks again Amy.

  36. Mary Joy says:

    Thank you so much for this information.

  37. Elaine Kelly says:

    I have printed off your formulas for purchasing fabric. Very helpful. Thank you.

  38. Maureen Ronolo says:

    Thanks for the tips Amy! I purchased the 12.5″ and 4.5″ square rulers yesterday (50% sale!) and measured my first block on the BOM. Oh I SO miscalculated my seams! Changing the needle and checking the rotary blades are great reminders too. Ready to do this thing now! :D

  39. Nancy Todd says:

    I’ve never used spray starch. Particularly with larger blocks, I have struggled with the fabric shifting when I handle or sew it. The starch would give it more body. I will give it a try. Thank you!

  40. Karen Hynes says:

    Wow Fabulous informationa I love your site with all it’s details Thank you for helping us all out

  41. Margaret Blyth says:

    Thanks so much for these tips! Now I know what you mean by a ‘scant’ 1/4” seam!

  42. Marilyn McGahan says:

    These hints are excellent. I learned about 1/4 inch seams the hard way; your explanation is very helpful in determining what to do on my sewing machines to make sure my blocks will be what they should be. I’ve always had to depend on quilt shop personnel to tell me how much backing and binding I needed. So I especially appreciate the easy way you gave to figure these amounts. I’m headed to the quilt shop this afternoon and will see how close I’ve come to the amount of fabaric they recommend I purchase for binding two different quilts.

  43. Kathy says:

    I don’t quilt, but like to sew, especially home decor, occasionally for my 8 year old Grandaughter and her ‘Just like me doll”. (Although, she is quite a fashion conscious and trendy little girl now and it’s hard to sew for her. (She also lives out of state :( …….. Aaaany way these tips apply to all my projects, and when younger I disregarded my Mom’s advice, because of lack of patience. And I didn’t think it really mattered—wrong. Older and wiser now—and with more time.
    I do hate the math especially for window treatments, isn’t there a magic tool for this? I figure and re-figure and always have to take in, let out, re-cut, add-on etc……………

  44. Pam French says:

    This is a great help. I continue to struggle with the seam size. Practice and measure!

  45. Sue Whited Holerson says:

    Ahhhh. I’ll bet I now know why my asterisk block was so puckered. I think I did each one of these things wrong – beginning with ironing instead of pressing. tsk tsk. Thank you for the information!!

  46. Lynn Meyer says:

    Thank you so much Amy! I will try these tips and I’m sure they will help throughout the year.

  47. Lorraine Whiteman says:

    Thank you for your very direct steps to piecing it will be very helpful

  48. Donna says:

    Thank you for the photo showing the 1 /4″ seam and scant 1/4″ seam. I’ve always been confused about exactly how to place my ruler.

  49. This is great common sense. What every quilter should know. I really need this quilting guru!

  50. Carolina says:

    You are right, it never hurts to review the basics. Thanks for the review. I’ll definately start using a ‘scant’ 1/4″ seam.

  51. Janita says:

    Thank you, Amy.

  52. Kathy Papineau says:

    Thank you for all the wonderful info……….the scant 1/4″ seam has been a hard one for me to learn but after these wonderful tips it has definately made a difference in the accuracy of my piecing! Thanks Amy

  53. Olive Fleming Drane says:

    This post has brilliant tips! Many thanks from Aberdeenshire Scotland. Your course on block of the month has been truly inspirational for my quilting, bring a new enthusiasm! Many thanks.

  54. Missy says:

    I found all of the tips extremely helpful. I do have a question though.

    Would you suggest spraying the fabrics with starch and pressing before cutting the pieces, after cutting the pieces, or after piecing the blocks?

    1. Support says:


      I would suggest that you spray the fabrics with starch after you have pieced the blocks, but before you piece the actual blocks together!

  55. LottieSue says:

    Because the “Scant” is key to perfection in quilting Craftsy should make it available as a free teaching offered with all their quilting classes. In Amy’s quilting class a greater percentage of the problems that come up with our blocks boils down to the “scant”. Please offer this it will end much confusion and frustration.

  56. Debi says:

    I like your ideas. The only problem I have had is the Fautless Starch. I bought two different cans and neither of them spray a nice even spray.

  57. valerie says:

    Hi, I am looking to try my hand at making a quilt. I have a lot of clothing I have been saving to use for this project. Problem is, while my ambition is there I am totally green to quilting. I have a simple brother sewing machine but not much else. This tutorial is very helpful, thank you. Is there any other suggestions you could impart to help me in my endeavor.

  58. Kathy says:

    Hi, I found your info very clear and informative, as a brand new self-taught guiltier, and I would like to follow this site. Could you please let me know how I can do this. Thanks in advance.

  59. Michelle says:

    I’m making a quilt for a baby, if I use starch should I wash the quilt top before stippling or after its all finished?

  60. Laurie says:

    Thanks for this!! These are awesome tips!