Once you move on from simple squares to more interesting patchwork designs, you may run into a few problems when stitching smaller units together into a block.

For example, have you ever joined a square to a Flying Geese unit, and wondered why the square is sticking out at the bottom…….?

It’s tempting at this stage, to think that the measurements in the pattern were wrong, and trim off the “extra” – but this is really not a good idea as now it will be too small for the next stage……. One early mistake will lead to multiplying problems later on as you continue with the block.

So, if you know that you are cutting accurately, stitching an exact 1/4″ seam and pressing as you go – where have you gone wrong?

The key to this problem is knowing how to line up the edges of the pieces correctly when making the Flying Geese – it’s nothing to do with the square at all.

The Flying Geese unit should finish looking like the one on the left, not the one on the right.

In the correct one (on the left), there is enough fabric to form a seam allowance beyond the point of the “Goose” so that the point doesn’t get chopped off when the next seam is stitched. The diagonal seams correctly go to the corner.

In the one on the right, can you see that the yellow triangle has been shifted down? It’s not in line with the top of the large triangle, and sticks out beyond the bottom edge.

Also, when the top of this Flying Geese unit is stitched onto anything else, the point will be cropped off in the seam allowance.

So, what went wrong? It’s all to do with how the pieces are lined up before being stitched together.

Getting it right – basics first

Let’s start by going back to basics. It’s obvious that if you are joining together two shapes exactly the same, such as two squares, or two half-square triangles, you just put the two shapes on top of one another, line up everything, and stitch your seam. The edges of the new unit are lined up properly with no bother.

Joining different shapes

However, if the pieces you are joining are different shapes, you need to be more careful.

If you choose to make a single Flying Geese unit from three triangles, then lining them up correctly is not as simple.  For the finished edges to end up the same length, the triangles need to be cut so that the edges of the fabric pieces are not the same length (because of the geometry) – the smaller triangle has a longer edge than the big triangle.

The reason for this is because each triangle has one square (right-angled) corner, and two corners with sharper points (45 degrees) – and at the top of the Flying Geese unit, you are joining different types of points together. The seam allowance (as shown by the double headed arrow) is always 1/4 ” but to achieve this, the corner needs to extend more on the sharper points.

So, do you line up the triangles with the outer points together, the inner ends together, or the centres together?

I have stitched some samples to show what happens for each of these – and I hope that it might help you to understand.

Line up outer points – correct

The small triangle is lined up correctly here over the larger triangle.

Can you see that I have lined up the outer corners of the small and large triangles? This means that at the top of the large Dark triangle, one sharp point of the small Light triangle sticks out beyond the square corner. However, the stitching line is what matters, and as this goes from the place where the edges of the two pieces cross over, then when the triangle is pressed out, it looks right.

When the second small triangle is added, the outer corners (where two sharply pointed corners meet) are again the ones which are lined up:

At the centre top, the sharply pointed inner corner of the small Light triangle sticks out a long way over the square corner of the larger triangle – well over the seam just stitched. However, this means that the stitching line again goes from the place where the edges of the two triangles cross over.

This gives the correct Flying Geese unit ready to stitch into the block.  When the square is stitched on, the point at the bottom right of the Flying Geese unit is perfectly placed 1/4″ in from the edge, so that it not get chopped off when the bottom seam is stitched?

Line up middle or inner points – not correct

It is useful to see what it looks like if the triangles are NOT lined up correctly – then if you see this, you will know why it will cause problems later!

If the middles or the wrong end of the triangles are lined up, then when the small triangle is pressed out, a little will protrude at the bottom.

This may not look serious, but the problems become more obvious when both small triangles are attached:

When you try to stitch the FG unit onto another unit at the side, you really realise that there is a problem.

Although you can stitch the square on, nothing will be lined up properly. If you stitch this, the points will all get chopped off, and it will be smaller than it should be, too.

Go back to the picture of how it should look, and check that you understand the difference.

A good general rule is that where pieces have the same type of corner, these should line up exactly, but if different types of corner meet, then the one with the sharper point will stick out more.

To be honest, this is one reason why I wouldn’t normally make Flying Geese units from pre-cut triangles.

Instead, I use quick piecing methods, particularly if I am making lots of Flying Geese (for some instructions on how to do this, see the links at the end of the excellent blogpost by Chris Franses.)

Two of my projects in the Shop which use them are the Jack-in-a-Box, and Catherine Wheel.Both of these use another method I have devised which avoids fabric waste. This makes additional half-square triangle units at the same time, which are then used for the pieced border.

Can you spot the Flying Geese?


Catherine Wheel

If you just want a quick try-out  of Flying Geese units, they appear in many different blocks. Here are two easy ones that you might like to try:

Evening Star block
Dutchman’s Puzzle block

Free download patterns are available in the Shop for the Evening Star block and the Dutchman’s Puzzle block. These are the start of a “Block Library” which you can use to practice techniques, or to combine into larger projects.

Precision patchwork is possible – keep asking for help so that you too can achieve great results.