Rainbow Quilt Block Tutorial

I am so excited to have another free tutorial for you! And two tutorials in one week, how exciting is that?!

Ever since I released my Over The Rainbow Tote pattern I have been wanting to make the block into a quilt. I have decided to experiment this year and try posting free patterns here on my blog, and since it is dreary January in the Pacific Northwest, starting my free patterns and tutorials with this rainbow block feels perfect! And in case you were wondering, this block is a bit different than the one in the pattern.

So let’s get quilting! This will make one 18.5″x18.5″ quilt block. If you are making more than one rainbow block you will just need to add in these same yardages per block. If you have any questions, please feel free to ask in the comments below.

Supplies (Per 18.5″x18.5″ block)

• (3) Fat Eighths For Arcs or Jelly Roll Strips

• (1) Fat Quarter For Background

• Basic sewing supplies- cutting mat, rotary cutter, cutting rulers, sewing machine with needles and thread, scissors, etc.

I am using a Jelly Roll. The smallest and medium arcs are no problem and you can easily cut all the pieces from one strip. The largest arc needs 43.5″ of width. Some of my strips were *just* wide enough, with me having to cut a bit into the selvedge, as shown above, but within the seam allowance. But some of my strips were not quite long enough. I made sure to pick strips that I had duplicates of for the longest arcs so that I could use the spare for an extra piece if necessary.

Cutting Chart

Fabric	Cut- Width by Height
Smallest Arc Fabric (A) 1 Fat Eight or 1 Jelly Roll Strip	(2) 2.5″x7.5″ (1) 7.5″x2.5″ (2) 1.5″x1.5″
Middle Arc Fabric (B) 1 Fat Eight or 1 Jelly Roll Strip	(2) 2.5″x9.5″   (1) 11.5″x2.5″ (2) 2.5″x2.5″
Largest Arc Fabric (C) 1 Fat Eight or 1-2 Jelly Roll Strips	(2) 2.5″x11.5″ (1) 15.5″x2.5″ (2) 2.5″x2.5″
Background Fabric 1 Fat Quarter	(2) 2″x13.5″ (2) 18.5″x3″ (2) 2.5″x2.5″ (1) 3.5″x7.5″

Cutting assumes non-directional fabric. If your fabric is directional you may need to add a bit more for the middle and largest arcs.

Just a note- when I write my pdf patterns I normally use the fraction for measurements, but on the blog they were not formatting how I am able to in inDesign. I used the decimals instead for measurements for ease of readability in this format.

1. I like to lay out the block on my cutting table and work from there. This helps me to see how everything lines up and helps me when I am assembling the block. 

Just a note- Ummm yeah, if you look closely I totally miscut a couple of these pieces. But I didn’t notice until I had already started, so this picture will have to do!

2. Mark a diagonal line from corner to corner on the wrong side of both of your 1.5″ Fabric A squares. Place the squares on the top short side of the 3.5″x7.5″ background piece, with the diagonals facing each other. That Sewline pencil* is my favorite for marking. I have the trio one* and liked it enough I recently bought this just pink version since I was always out of the pink lead.

3. Sew ON the lines. Use a quilting ruler and rotary cutter to measure and trim .25″ away from both sewn lines. Press the sewn triangle corners up and out. You can also use the seam tape like on my machine from Cluck Cluck Sew* so you don’t have to mark all of your lines.

4. With RST place (1) 2.5″x7.5″ Fabric A rectangle on a long edge of the background rectangle from the last two steps. Sew in place and repeat on the other side of the background rectangle with the other 2.5″x7.5″ Fabric A rectangle. Press both seams toward Fabric A. 

5. Mark a diagonal line from corner to corner on the wrong side of your (2) 2.5″ Fabric B squares. With RST match up the squares to the ends of the 7.5″x2.5″ Fabric A rectangle with the diagonals facing each other.

6. Sew ON the lines. Use a quilting ruler and rotary cutter to measure and trim .25″ away from both sewn lines. Press the sewn triangle corners up and out. 

7. With RST place the 7.5″x2.5″ Fabric A rectangle with Fabric B corners on top of the background and Fabric A rectangle. Sew in place and press seam toward Fabric A rectangle. 

8. With RST place 2.5″x9.5″ Fabric B rectangles on the side of the background and Fabric A rectangle. Sew in place and repeat on the other side of the background and Fabric A rectangle with the other 2.5″x9.5″ Fabric B rectangle. Press both seams towards Fabric B. 

9. Mark a diagonal line from corner to corner on the wrong side of your (2) 2.5″ Fabric C squares. With RST match up the squares to the ends of the 11.5″x2.5″ Fabric B rectangle with the diagonals facing each other.

10. Sew ON the lines. Use a quilting ruler and rotary cutter to measure and trim .25″ away from both sewn lines. Press the sewn triangle corners up and out. 

11. With RST place the 11.5″x2.5″ Fabric B rectangle with Fabric C corners on top of the background and Fabric A+B rectangle. Sew in place and press seam toward the Fabric B rectangle. 

12. With RST place (1) 2.5″x11.5″ Fabric C rectangle on the side of the background and Fabric A+B rectangle. Sew in place and repeat on the other side of the background and Fabric A+B rectangle with the other 2.5″x11.5″ Fabric C rectangle. Press both seams toward Fabric C. 

13. Mark a diagonal line from corner to corner on the wrong side of your (2) 2.5″ background fabric squares. With RST match up the squares to the ends of the 15.5″x2.5″ Fabric C rectangle with the diagonals facing each other.

14. Sew ON the lines. Use a quilting ruler and rotary cutter to measure and trim .25″ away from both sewn lines. Press the sewn triangle corners up and out. 

15. With RST place the 15.5″x2.5″ Fabric C rectangle with background fabric corners on top of the background and Fabric A+B+C rectangle. Sew in place and press seam toward the Fabric C rectangle. (Whoops, missed the photo on that step!) Then, with RST place (1) 2″x13.5″ background fabric rectangle on the side of the rainbow block. Sew in place and repeat on the other side of the rainbow block with the other 2.5″x13.5″ background rectangle. Press both seams toward background fabric. 

16. With RST place (1) 18.5″x3″ background fabric rectangle on the top of the rainbow block. Sew in place and repeat on the bottom of the rainbow block with the other 18.5″x3″ background rectangle. Press both seams toward background fabric. You have now finished your rainbow!

So fun! You can use this block in so many ways! You could throw a batting and backing fabric on it, practice your free motion quilting on it, throw on a binding and have an adorable wall hanging. You could quilt the front and make a fun pillow for your couch or a child’s bed. You could sew three of them and turn them into a cheery table runner. You could make four or six of them and have a happy baby quilt. I hope you let your imagination run wild! I have started on a twin size quilt that I will share a tutorial for once I get it finished. Here is the start:

I hope you make some cute rainbows and I would love if you share them with me. You can use the hashtag #B’sRainbowBlock on social media, or leave me a comment or a link below.

Happy Quilting!

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