I recently made a nine patch sqaure and it should have been twelve inches when I finsihed. It was about ten inches sqaure. I used a 5/8 seam allowance. I made a second square and I used a 3/8 seam allowance and it is still smaller than the twelve inces the direction says it should be. What seam allowance am I supposed to use for peicing quilts?

Your seams are too large. They should only be 1/4 inch.

most patterns call for 1/4". Hope this helps :)

1/4 inch or scant 1/4 inch is normal.

So sorry for your grief. They have to be very acurate 1/4 inch. The best thing I invested in, is a 1/4 foot. Saved me alot. Hope you have better luck. Suzanne

The standard seam allowance when piecing is 1/4", or what is known as a "scant" 1/4" - which is a thread or two under a true 1/4" to allow for thread thickness etc.

Unless stated otherwise, seams are assumed to be 1/4.

Thanks everyone! I will now try the 1/4 seam allowance. I just knew that had to be the problem. I saw something at the store earlier that was a piece of plastic that was 1/4. I wondered what it was used for and now I know. Eventually, I guess I will find out all the secrets of the beautiful quilts everyone shows on this site.

If you've ever sewn clothing it's a little hard in the beginning of a quilt journey to remember the 1/4 seams!
That's what MY problem was :)

Been there done that, also tried the 1/4 inch on some clothes once....

I had the same problem when I first started quilting. I had to unlearn the automatic 5/8 seam allowance that I learned many years ago. Get a 1/4 inch foot with the metal guiide on the side. It has helped me match up my seams more than anything.

you will not be the only one who didnt know 1/4 inch was the universal seam allowance for quilts but even knowing a 1/4 inch seam is crucial dosn't make sewing them easy--recently after quilting for 10+years i invested in a 1/4 inch foot -- bliss--there is some kind over addictive thrill when seams meet perfectly---also once you know the rule and why you can with adjustments break it

There are tutorials available about how to get an accurate sewn 1/4 inch seam both here and on the web. There may also be a video on the subject at You Tube as well as some quilt shops online may have some instructions.

If after reading through some of the tutorials you still have questions please post them so we can help with the learning curve of the scant 1/4 inch and any other issues.

Glad to have you here and quilting with us.

Pam M

Here's a good tutorial on how to achieve a perfect 1/4" seam allowance.
http://www.quiltingboard.com/t-89997-1.htm

It's hard to switch your mind like that. I sewed clothes for years and was so used to the 5/8". Then I got some kwik sew and stretch & sew patterns and they were 1/4". That took some getting used to. By the time I started quilting I was used to a full 1/4" so now I have to figure out the scant 1/4" every time.

I actually bought the plastic thingo and it's been very handy! The only time you break the quarter inch rule is generally when sewing denim/corduroy/ragging. Took me a time to get it, but once you do, everything will fall into place (literally!).

So, the plastic thingo works? It looks like you mark your edges and then sew on a line.

Yes, I have made clothes all my life. The 1/4 inch seam allowance was not covered in anything I read.

I bet that did not work well for the clothes. I am so glad I was not the only one to do this on a quilt.

I am going to see if I have a foot in my kit with my Janome or if I can buy one. I love the gadgets as long as they work!

I still find it hard to go back to 5/8" seams for the few garments I still make, after all these years of 1/4" sewing.

I keep drifting down to 1/2" seams.

Wow, you've been making clothes haven't you? I know it's hard to switch down to 1/4" seams. It doesn't seem like it should be secure enough to wash multiple times but it does work well. I had the exact opposite problem I found some nice fabric and a easy pattern for a jacket and thought I could whip it out easily. I completed a whole bunch with 1/4" seams. Luckily a friend of mine came over and saw what I was doing and reminded me that I would be wearing it and should read the pattern correctly. Oops, luckily I could go back and resew everything.

Yep...when I was starting out it was really useful and I still hold it up next to my seams just to make sure I'm still on track...it is only a simple thing but I have found it one of the more useful gadgets.

Luckily Bernina has 1/4 inch foot which is wonderful..