3 tests every quilt block should pass

Today I’m sharing three simple tests that every quilt block should pass. They’re especially worth doing when you’re making a scrappy quilt, where you may have picked a wide colour variety for the blocks.

Before we get to the three tests, though, there’s an entrance exam. If a block doesn’t pass that, it cannot move further in your project.

The entrance exam for quilt blocks: sewing a test block

If you’re making quilt blocks following a pattern, first sew one block using expendable fabrics. Not poor-quality fabrics though, because if your test block colours work with the rest of the quilt, you may very well end up using it in your project.

If the test block turns out to be of wrong size, you can also use it as part of your quilt backing. So it is worth picking decent fabrics even for your test block, though fabrics that you aren’t in love with.

I often work out my own measurements for blocks, so I’ve sewn more than my fair share of test blocks. Once I had a particular block in mind and ended up sewing three different versions before I was happy with the proportions.

The correctly sized block is on the upper left:

A test block is a definite must if you’re designing your own block based on a photo or a pattern you’ve only seen. I’m glad I tested two such ideas because they turned out unsatisfactory.

My first idea was better, but my fabric choices were so strange that I could not imagine a quilt sewn of these blocks:

The other test resulted as “meh” after a labour-intensive process. Not worth the effort:

Before making the “Johan nyt on markkinat!” quilt, I sewed one failed test block. I must have done something wrong because the block did not come out square. It was also far too big!

Two years after that, I drew a properly sized paper template for the block and sewed a quilt-ful of blocks using the folded paper piecing method. These were the first two, and though they were my test blocks, I used them in the actual quilt:

Once a block design has passed the entrance exam, your blocks should pass three more tests.

Test 1. Are you using correct materials in your quilt block?

Are all the fabrics you’re using made from the same material, and are they equally durable?

If you’re making something that’s meant to be used, such as a quilt, a bag, a table runner or a zipper bag, all your pieces (and blocks) should be of the same type of fabric. You’ll be making things easier for yourself in the sewing phase, and you’ll also ensure that the finished blocks will all wear at roughly the same rate.

So don’t mix synthetic fabrics with quilting cottons like I did in this ancient block:

You’ll do well to avoid mixing lighter and heavier-weight cottons, and to make sure none of your fabrics bleed, especially if your block combines very dark fabrics with very light ones.

Test 2: Is the block the right size?

Either sew your block accurately to size or sew it close to the right size and trim it with your rotary cutter. When every block is exactly the same size, assembling the quilt top becomes so much easier.

Even if trimming means that some of the points in your blocks will be blunt instead of sharp, it is more important to have uniformly sized blocks. The perfect, needle-sharp points are only noticeable when one looks at them from up close.

If you are in love with the points and your blocks consequently vary in size, you will have to ease or stretch your blocks when sewing them together. This means that your quilt top won’t lie flat. And when it comes time to quilt it, you’ll have made life much harder for yourself.

So if your quilt design is based on same size blocks, make sure they are indeed of same size.

Test 3. Does your block have proper value contrast?

Every block has to pass the contrast test: do the different pieces have enough difference in value? After all, the whole point of a quilt block is for the design to show.

Value contrast matters more in quilting than we may think. The human eye wants to find patterns, and it is better at spotting differences in value than differences in colour. Your eye will find the patterns more easily from the changes in value – from the contrast between light and dark areas. In this photo, you can see that some of the blocks have good value contrast, others do not:

Value contrast is more important than your colour choices. We may think that contrast between colours will make patterns stand out, but it almost always does not work well. Your eye will see the different colours, but if they are of the same value, one colour will blend into the other when the patchwork is viewed from a distance.

As an example, see the pale lilac and green squares in this photo:

You can see that they are clearly of different colour, but squint your eyes or look at the photo from further away, and the colours will blend. If you relied on this colour difference in your block, its pattern would not be visible.

You can use this knowledge to advantage. For example, in the “All the Balls in the Air” quilt from 2017, the secondary pattern, the “circular shapes” aren’t entirely light or dark:

If I’d wanted the circles to stand out more clearly, I would have made sure the pieces creating the secondary pattern were always noticeably lighter or darker than the bow-tie pieces.

Your takeaway: A block design will disappear if all the pieces are the same value. Even if those same-value pieces are of different colour, the design still won’t be properly clear.

In summary

That’s it. After the entrance exam – your test block – make sure your block passes three tests: materials, size and value contrast.

Once you’ve got those things right, you can let your creativity loose while sewing your blocks and arranging them into a quilt top.