Inset Curve Star Tutorial

I am really excited to share a photo tutorial today for inset curve stars. If you are comfortable sewing drunkard’s path blocks, you can sew an inset curve star; the inset curve star does require partial seams, but I promise they are really gentle and easy to do! This tutorial will create a 24 1/2″ unfinished / 24″ finished block and requires the use of 6 1/2″ unfinished / 6″ finished drunkard’s path templates along with standard sewing tools and supplies.

May 2023 Update: Purchase a PDF file with 6″, 5″, 4″, and 3″ finished drunkard’s path templates here!

Preparation

To make your own inset curve star, you will need five 12 1/2″ squares. One 12 1/2″ square will become the inset star and for the purposes of this tutorial I am using the solid yellow shown on the right in the photo above. The four background 12 1/2″ squares can be anything else that you like. For this tutorial, I pieced two curve star blocks and two 12 1/2″ unfinished square in a square blocks. (Side note: how fun is the metallic pearl bracelet print?!)

There are so many options for piecing inset curve stars. I’ve sewn up a few other variations that I want to share to get your creative mind thinking about what you would like to try.

For my first test inset curve star, I used a purple print 12 1/2″ square for the inset star, (2) yellow print 12 1/2″ squares, and (2) green print 12 1/2″ squares.

For each quadrant of Sky Full of Stars, I used a print 12 1/2″ square for the inset curve star, three pieced curve star blocks, and a solid background 12 1/2″ square.

First Curve

The order that the curves are pieced for the inset curve star is very specific. Because of the specific order, I highly recommend arranging the 4 background blocks in the order and orientation that you would like on a design wall and labeling them (Note: they will be used in this order: 1. upper left, 2. lower right, 3. upper right, 4. lower left). The first curve we will piece will be in the lower right hand corner of the upper left background block.

To prepare the first curve, start with the upper left hand background block. We will be using a 6 1/2″ unfinished / 6″ finished drunkard’s path convex template to cut a curve in the lower right hand corner of this block, so if the block is directional, be sure that you are cutting the curve from the correct corner of the block.

Because I am right handed, I orient my blocks as shown above when cutting curves, so I take care to make sure that I am cutting from the correct corner of the block if the background block is directional. Because this background block already has piecing seams at the halfway point along each side, no additional preparation was needed prior to lining up my template. If you are working with a single 12 1/2″ square fabric, fold the square in half and finger press seams to mark the halfway point along each side of the block.

When lining up the 6 1/2″ unfinished / 6″ finished convex drunkard’s path template, the reference seam lines should touch the already sewn seams or the finger pressed halfway marks along the side of the block.

Fold the curve in half, aligning the seams or finger pressed halfway locations and finger press a fold at the center of the curve. Fold each end of the curve back to meet the center curve location to finger press a fold a the quarter curve location, making sure that the seam or finger pressed half block location meets the center curve. When complete, the curve should have (3) marks or finger pressed locations: the center of the curve and the quarter points along the curve.

Prior to making the first curve cut in the star fabric 12 1/2″ square, finger press, iron, or measure and mark the center of all (4) sides of the square on the right side of the fabric. Make sure that the mark you make is at the very edge and less than 1/4″ long so it will be hidden by the sewn seam. NOTE: If your star fabric is directional, place the print in the orientation you would like it to be pieced in the final block and make the first cut in the upper left hand corner.

Using the 6 1/2″ unfinished / 6″ finished drunkard’s path concave template, make the first curve cut in the star fabric. Align the two short straight edges of the template with the sides of the square, and if your templates have reference seam lines etched into them like the templates I use from Jen Carlton-Bailly, you can double check that the marked center lines of the star fabric square line up with the reference sewn seam lines.

TIP: Reserve the cut away quarter circle for a future project, noting that it can be used with a 5 1/2″ unfinished / 5″ finished drunkard’s path convex template.

After cutting the curve, but before removing the template, if your template allows, mark the center of the curve. Otherwise, fold the cut curve right sides together and align the edges and finger press the center of the curve. Fold the edges of the square in to meet the center of the curve and finger press / mark the quarter points along the curve as well. When complete, the curve should have (3) marks or finger pressed locations: the center of the curve and the quarter points along the curve.

With the star fabric on top, pin the cut and marked star curve to a marked background block curve right sides together. Start by aligning the centers and pinning. Next, pin the edges of the star curve to the halfway point along the sides of the background block noted by seams or the finger pressed folds. Finally, pin the marked quarter points along the curves.

Note: I recommend pinning with the heads of the pin facing away from the seam.

With the star fabric on top, use a scant 1/4″ seam allowance and sew the first curve seam, starting your seam 2-3 stitches in the background block just before the start of the star fabric and ending in the background block 2-3 stitches past the star fabric. (Note: I use an adjustable seam guide that is bolted to the top of my machine.) A scant 1/4″ seam is a seam that is a thread width smaller than a true 1/4″ seam allowance. It is important that the first two curve seams in the inset curve star block are sewn with scant 1/4″ seams and that the third and fourth seams are sewn with true 1/4″ seam allowances. More details about this importance are included when the third curve seam is sewn.

TIP: Use a stiletto with your right hand to keep fabric aligned and gently nudge the pins out of the way of your needle with your left hand as needed.

After sewing your scant 1/4″ seam, press toward the star fabric.

Second Curve

Repeat the same cut, mark, pin, sew with a scant 1/4″ seam, and press toward the star fabric process you completed with the first curve to make the second curve. Make sure that the second curve is cut from the opposite corner of the first curve in the star fabric (lower right hand corner) and in the upper left hand corner of the lower right hand background square.

Third Curve

Repeat the same cut and mark process for the third background curve. Make sure that the third curve is cut from the lower left hand corner of the upper right hand background square.

The third curve should be cut from the upper right of the star fabric. When cutting the third curve in the star fabric, you may find that the concave template does not align with the remaining edges of the star fabric. The most important thing to keep in mind when aligning the concave template is that the reference seam lines should touch the already sewn seams; these will be the points of the star.

When folding in the edges to create the quarter curve reference points, be sure to align the edge of the star fabric with the center mark.

Prior to describing how to pin the third seam to prepare to sew it, I wanted to show the blocks in their orientations to point out why the third (and fourth) seam is a partial seam. We will be sewing the upper left hand background block not just to the inset curve star, but also to its two adjoining neighbors. Once pinned together, the biggest challenge with this partial seam is dealing with the bulk of the blocks that are already sewn together. My best advice is to carefully pin and sew slowly to make sure you are not accidentally sewing through any additional layers of fabric.

With the star fabric on top, pin the cut and marked star curve to the marked background block curve right sides together. Start by aligning the centers and pinning. Next, pin the edges of the star curve to the halfway point along the sides of the background block noted by seams or the finger pressed folds. Take care here if you will be matching pieced points to make sure the points are aligned. Then pin the ends of the blocks together and pin the marked quarter points along the curves. The bulk of the fabric will be on top, and the background block will lay flat on a table and your sewing machine as you sew the third seam.

Using a full 1/4″ seam allowance, begin to sew the third seam. The first third of the seam is a straight seam joining two background blocks.

When you reach the star fabric, the third seam will transition to the curve portion of the seam. By using a full 1/4″ seam allowance here, the needle should pass through the earlier curve seam right at this transition point which will define the inset curve star point. Continue sewing along the curve, using a full 1/4″ seam allowance. Note that as you transition from the straight seam and into the curve seam that the needle should pass to the right hand side of previously sewn seams.

At the other end of the curve, the needle should pass through the earlier curve once again right at the transition point out of the curve seam and into the final straight portion of the third seam.

If you are joining pieced blocks that have points meeting at the ends of the curve seam, like in the example above, I recommend pressing the third seam open. If the background block that you sewed the third seam to is a single piece of fabric (no seams), then I recommend pressing the third seam away from the star fabric / toward the background block.

Fourth Curve

If direction matters, make sure that the fourth and final curve is cut from the upper right hand corner of the lower left hand background square. Repeat the cut, mark, pin, sew with a full 1/4″ seam, and press open or toward the fourth background fabric block for the partial fourth curve.

Be sure to take your time aligning any points that may join at the ends of the curve seam and remember to sew the seam with the star fabric on top while keeping the fourth background block flat on your sewing machine.

TIP: If you want to seam rip any portion of the partial seams, I recommend working from the background fabric square / bobbin thread side of the block to get started. There are a lot of criss-crossing seams and you don’t want to unpick the wrong seam.

The finished inset curve star block will finish at 24″ and should measure 24 1/2″ square after the fourth seam is sewn.

This process will work for any square drunkard’s path templates. For example:

• To make a 12″ finished (12 1/2″ unfinished) curve star block, use 3 1/2″ unfinished / 3″ finished drunkard’s path templates and begin with a 6 1/2″ square for the star fabric and (4) 6 1/2″ background squares.
• To make a 16″ finished (16 1/2″ unfinished) curve star block, use 4 1/2″ unfinished / 4″ finished drunkard’s path templates and begin with an 8 1/2″ square for the star fabric and (4) 8 1/2″ background squares.
• To make a 20″ finished (20 1/2″ unfinished) curve star block, use 5 1/2″ unfinished / 5″ finished drunkard’s path templates and begin with a 10 1/2″ square for the star fabric and (4) 10 1/2″ background squares.

I’d love to see your inset curve star blocks and how you use them, so be sure to tag me @quiltingjetgirl and use #insetcurvestar when sharing!