Watson

I have a 4 patch that is 4 1/2" exactly. I layer it with a black fabric that is also 4 1/2" exactly.
I draw a line down the centre, corner to corner and then sew a scant 1/4" either side. I cut down the line in the centre to make two HST's, but they never turn out square. One side is always slightly larger than the other.
This should work, right?
What am I doing wrong?
Can I just trim that? It's like that on all of them so far.
Picture added to show where it overhangs more than the bottom.
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Watson

Garden Gnome

I'm wondering if, when you draw the line, the tiny width between the ruler and the tip of the pen is big enough to make a difference. Even if it's only one thread's difference, I think it would multiply by 4 by the time you use that line to measure from and stitch on both sides. So, over by two threads on one half, under by two threads on the other. And when you place two pieces together, the measurement is off.
You could check this possibility by putting your ruler on a lined piece of paper, then use your pen to draw the line. If it's over by any width at all, it is distorting your measurements.

EasyPeezy

Looks like you are attempting a Cat's Craddle block, right?
If so, there is a method to use to avoid losing your point.
I'll see if I can find the tutorial. I believe someone posted one
here.

Watson

No idea, EasyPeezy, just trying to use up some blocks. Nice to know there is a name for it.

That could be it, Garden Gnome...I'll have to check that.

Maybe if I make it even more scant and then cut it down so it all matches? It's for a border that I'm making so the size is up to me.

Watson

EasyPeezy

Found another tutorial. It's also called Shaded Four Patch.

http://katisquilting.blogspot.ca/201...sy-street.html

nativetexan

if you want a hst that is 4 1/2 after being made , you start with 5 1/2 inch squares. then when done, trim using the 45 degree line down the seam line. trim two sides, turn hst 180 degrees to trim the remaining two sides. good luck. Ah, i see the photo in the link. not the same but almost. again, good luck.

PaperPrincess

THis is why many people oversize, then trim. I love bloc loc rulers for this. Pricey, but worth it.
Also, if you look closely the ruler is of the seam line in the upper right corner.

Prism99

This is one reason I don't make entire quilts out of HSTs; mine are always like that! Honestly, I think the reason is because you are sewing along a bias on both fabrics. My reasoning is that the feed dogs move the bottom fabric at one pace while the presser foot is stretching the bias of the top piece.

One way to test this theory is to cut 2 pieces of paper 4.5", mark them, as sew just as if it were fabric. Paper does not have a bias so theoretically the result should be more perfect than with fabric.

If the paper turns out better, then it would help to *heavily* starch the fabric before cutting. Although this won't completely stabilize the fabric bias, it will reduce any stretching or distortion that occurs while sewing.

Using a walking foot would probably help too, especially if the fabric is heavily starched. Reducing presser foot pressure might help too.

I think some sewing machines cause more distortion than others because there is more of a discrepancy between the presser foot and feed dogs.

Edit: Or, my theory could be completely wrong and the discrepancy comes from slight variations in cutting, sewing, and pressing.

For example, especially if using steam, ironing from the right side, and ironing the seam to the black fabric, the iron could be stretching the black fabric out of shape. Some fabrics have more stretch along the bias than others, and if you are moving the iron from the printed fabric to the black fabric along the seam line, you are pressing the black fabric along its bias. Actually, this may be the better theory because the discrepancy is bigger at the corner of the black fabric, which is consistent with the iron distorting the fabric.

Are you pressing with steam? Pressing with a dry iron and using only the tip of the iron to press the seam might help. It would be moving the iron across the black fabric that would distort it. The bias runs not only along the seamline, but also perpendicular to that line, ending at the corner of the black fabric. The printed fabric, if on the bottom while ironing, would not be as distorted because you would be ironing it towards the seam line rather than towards a corner.

Sorry, probably too much speculation here......

bearisgray

Mine turn out like that, too,- even when I make super-scant seams.

So - I have also started doing the slightly over-sized squares and trim down after sewing the diagonal seams.

Macybaby

You need to trim both sides - make sure you line up the seam with the diagonal on the ruler, otherwise you'll loose your points.

I use my easy angle ruler, and cut triangles from a strip that omits the top point. For a 4.5" HST unfinished, I start with a 4.5" strip of each color.

When I sew them together, I rarely need to trim.

Though if I'm doing something that ends up less than 2.5" unfinished, I prefer to cut a bit larger and trim down. Smaller pieces are harder to keep square when sewing.