bearisgray

Again - this is not a new topic - but it may be new info for new members -

Seam width does matter - but not as much as - is the finished block/unit the size you intend it to be?

This is a good video to check what one is doing:

http://www.fonsandporter.com/article...s_Video_Lesson

Cutting also matters.

If one's "4.5 (4-1/2)" inch cut squares are actually 4.375 (4-3/8) or 4.625 (4-5/8) inches - it won't matter how "perfect" your seam allowances are - the end result will be off.

So - the point of this post is: If your units/blocks are not ending up the size you want them to be, the seam allowance is only one place that corrections /changes may need to be made.

QuiltnLady1

That is a good video . I am a little more laid back about the cut size since I know that I can work with a block that is cut no more than 1/8" off by matching it with a correctly sized block and sewing the seam allowance based on the correctly sized piece.

What is important to me is that the sewn blocks are the correct size. I always measure a sample sewn block to make sure I have the seam allowance I need. My favorite way to set my seam allowance is using a lined note card since the lines are 1/4" apart. The primary reason I check the seam for measuring the sewn blocks is I find that not all fabrics are the same weight, so the "scant" 1/4" seam my differ depending on the fabric. I like to build a "fence" to control my seam allowance since I have found that if I don't place my chair in exactly the same place, the width of the seam may wander because I have changed the angle I am looking at a line or the edge of the presser foot. The fence ( a stack of notecards or blue painters tape) give me a consistent guide that does not change if my chair moves a bit to the left or right.

bearisgray

Good suggestions. Some older machines have a seam guide that one can screw to the machine.I don't know if the newer ones do or not. Some machines also have lines etched into the top for guides.

SusieQOH

One thing I learned the hard way was to use the same machine throughout. I love piecing on my Featherweight downstairs but I was working on my Bernina and switched- bad idea.
Now I use one machine only per quilt.

bearisgray

One can use more than one machine - one just needs to "verify" that one is making the seam allowances are the same .

Granna of 5

.Quiltnlady1, you have solved one of my problems, I never thought about the position I sit in my chair each time being different, which it is, would cause my seams to be off. Thanks for this eye opener.