When is 4.5" not 4.5"?
 

When I'm making four patches, that's when.

I'm doing the Mystery Train Ride and have cut my pieces into 2.5" squares. When I sew them together they come out to everything except 4.5" blocks. Sometimes bigger, sometimes smaller, usually smaller.

I have moved my needle over And sewn a scant 1/4". I've measured the resulting seam and it is less than a 1/4". I've measured the cut pieces and they measure 2.5"...So, what am I doing wrong?

Hints? Tips? Someone want to come look over my shoulder while I sew? (I've got brownies.)

Thanks, Watson

Brownies? you said brownies? You have my attention!

The discrepancy comes when you stitch, and fold the seam back.
A bit of bulk from the thread and a bit of bulk from the fabric (each layer in the seam)
and a bit of loss in the 1/4" seam and it's soon out of whack.

You did the right thing by shifting your needle over, to make up for the adjustment.

One way to help figure it out is to take three strips 1-1/2" wide and stitch.
Press the seams and measure.
If all is good, then that should equal 4-1/2", right?
Now re-do it with three more strips, but adjusting your needle.
Press and measure.
Keep re-doing until you are where you want to be.

In theory ... this strip stitch and measure technique would be better done with more than three strips, as if you are just out a hair on each seam, then it would not equal what it should be.

Of course ... this all gets thrown out of whack if you work with a different fabric and/or thread.
One of the reasons that I really like Aurifil thread ... thinner and doesn't mess things up as much.


Make sense?
.............. now, do I get my brownies? :)
(now let's see, I could be there in what do you think probably about 2 hours?)

Check size of your needle as well as thread both in top and bobbin.

I wish we could come up with a term for where to sew instead of 1/4" seam. You don't measure the seam, you measure the resultant patch!
Here's a tutorial to the method described above:
https://www.quiltingboard.com/tutori...ce-t89997.html

Keep moving a needle until the center strip measurement is correct, then write down the settings on your machine and use something, like a piece of tape, to indicate where the edge of the fabric should be.

Two additional comments. Make sure you are pressing carefully and not stretching the seam (can you see the sewing thread?) or pressing a tiny fold at the seam. Also, although you have written the machine settings and possibly marked where the edge of the fabric should go, the fabrics and thread you use can affect this and you may need to adjust! I often will do a quick check at the start of a project to verify I'm still right on. I'd rather spend a couple minutes checking my seam then a whole lot of time ripping or fighting to get stuff to fit.

well if you haven't cut all the small squares, you could cut them a tad larger and then trim after sewn together. good luck.

What you say makes sense QuiltE, but don't the creators of the quilt patterns face the same bulk and thread issues as the rest of us. I use presencia thread, I press very diligently, I am very aware and careful with my 1/4" seam. This can't be rocket science. If you use a scant 1/4" seam to get the desired block size, at what point do you start jeopardizing the integrity of your seam? How many clicks over of the needle is too much? This is the part of piecing I find rather defeating. In my last quilt I was trimming frayed threads from my seams before I actually quilted the top so threads wouldn't show through on the top. The fraying wasn't bad, but you are dealing with cotton fabric and there is some fraying. Add that to a scant 1/4" seam and I fear my quilts may suffer with the test of time and washing.

Watson, are you pressing or ironing? It makes a difference. I also use Aurifil or Presenia thread. Both are thin but strong.

I live in Arizona so give my brownies to your favorite quilter! (If I qualify) lol

I have been quilting since 1992 and have yet to achieve the perfect 1/4 inch seam. I used to worry about it but, I figure since I am making all of the blocks, they will be off by the same amount. My quilt may be smaller than the next person's or I can always add another row. Four days away from 64, I think I have enough to furrow my brow. :)

SummitBay .... As I mentioned, different fabrics and threads make a difference to the end results.
Some fabrics are so thin ... others quite substantial. Yet they are all considered quilting cottons.

Threads ..... using a 50 wt? or 40? or 60? All are different thicknesses.
Likewise, double or triple strand thread?
Further, 50 wt in one brand is not necessarily the same thickness as it in a different brand.
To make matters worse and more confusing, dye content can affect the whole situation too.
Black threads often are seemingly much coarser, because of the dye content.

Others have already provided good advice, I just want to say I feel your pain. The 4-patch is the bane of my existence. What should be the easiest block in the world to do never seems to come out right for me even though I have no problem with other blocks. When I made my "quilt from h**l" I finally decided the only thing to do was to make them larger and trim to size.