Pinwheel Block tutorial with Tri-Recs Rulers + Ruler Giveaway!

I'd like to share with you how I used the Tri-Recs rulers to make the pinwheel blocks in the Pinwheels & Patchwork quilt  (free pattern here.)  And if you don't already have a set of these handy rulers, stay tuned to the end of the post for a chance to win a set from the Fat Quarter Shop! (giveaway has ended)

I bought these Tri-Recs rulers years ago and then they sat for a looong time because I didn't know how to use them!  Now that I know, they're super handy and you can do all sorts of fun blocks with them.  Today I'm just showing the pinwheel block, but once you get the hang of them, you can start just creating!

The pinwheel block for today is really just four triangle-in-a-square blocks that have been rotated and sewn together.  Let's get started!

First of all, cut a strip of fabric that is 6.5" x WOF (width of fabric).  You can keep it folded (the way it comes off the bolt) and that way you'll be cutting two triangles at a time.

Line up the "Tri" ruler on the strip of fabric as shown.  That nice flat edge on the top of the ruler is helpful here!  See how it lines up with the top of the fabric strip?

Use a rotary cutter to cut out one triangle, then flip the ruler over and line it up along that just-cut edge.  You're ready to cut another triangle!  Keep going along the length of the strip of fabric, cutting out as many triangles as you need.  For one block we only need 4 triangles.

Next up we'll be cutting the side triangle pieces using the "Recs" ruler.  Once again, cut a strip of fabric that is 6.5" x WOF.

See that notch on the top left of the Recs tool?  That notch will come in handy when you start piecing the block.  So make sure you trim that notch from the fabric as you cut!

  Line up the ruler as shown, and cut one triangle. 

As before, flip the ruler over and cut another one.  And then just keep flipping and cutting all the way down the length of the strip.  For our one block you'll only need 8 of these side triangles.

Time to sew!  Arrange one triangle piece with two side triangles as shown.  We'll sew one side first.  

Flip the side triangle over so the two pieces are right sides together.  Notice the bottom corner of the triangle?  

That notch you cut in the side triangle piece helps you line it up with the larger triangle.  The notch should line up with the bottom edge of the large triangle. 

Stitch along the side of the triangle with a 1/4" seam. 

Flip open the side triangle and press.  I recommend pressing open.

Now line up the second side triangle - making sure that notch at the bottom is lined up.  Sew with a 1/4" seam. 

 Flip open the second side triangle and press open.

This triangle-in-a-square (TIS) block should measure 6.5" square.  Repeat to make a total of 4 TIS blocks.  Take a minute to trim off any little dog ears on each block.

Arrange the four blocks as shown, taking note of how each one is rotated. 

 Sew the top two blocks together, and the bottom two blocks together, with a 1/4" seam.  Press seams open.

Now sew the two block halves together, being careful to line up that center seam.  Stitch and then press seam - this time press to one side.  The finished block should measure 12.5" square.  Fun block, right?  


Would you like to win a set of Tri-Recs rulers?  Just leave a comment below, telling me one thing on your Summer bucket list.  Giveaway ends Sunday July 2nd at midnight and I'll announce the winner here on Monday July 3rd.  And thank you to the Fat Quarter Shop for sponsoring the giveaway!  International entries welcome, one entry per person please.  Giveaway has ended - thank you!

Want to see what else you can make with the Tri-Recs rulers?**  Check out this pinterest board - filled with different ideas on what you can make using these two rulers!

And don't forget to go here and download the free pattern for the Pinwheels & Patchwork quilt.  Now that you know how to make the pinwheel blocks, this quilt's a breeze!  

**This post may contain affiliate links, which means I may receive a small commission (at no additional cost to you) when purchases are made through links found in this post.