Mrs October: Double Pinwheel

Two mirror imaged sets of 4 double pinwheel blocks, 8.75" unfinished, 8.25" finished size.

I have signed up for a charity quilting bee and each month one of us requests a block to be sent to them which will then be combined into a quilt for a young people's camp where they are reunited with siblings separated from them by the care system. Each child gets a quilt which should be of a good size. Anyway this month it's my turn to chose a block and colours and as so many of us make girly quilts this one will be for the boys with strong colour contrast between blues/navies and reds/oranges, mainly tone on tones, no flowers!
The block is one I used many years (16) ago to make a quilt for my baby grandson and I learnt it from an Eleanor Burns episode on Simply Quilts. Now she has a video on YouTube showing the many colour strategies you can use including a three colour version. 
I chose to cut 2.75" strips as they are fat quarter friendly but as big as possible, 8.75" unfinished, 8.25" finished.
The method results in two mirror imaged blocks either to make two separate quilts or one set as a border.

1. Cut 2 red/orange strips 2.75" wide and 20+" long and 
and 2 blue/navy. They can be the same or different fabrics.

2. Sew in pairs and press towards the blue

3. Cut into four 5." squares

4. Place the strip sets on top of each other right sides together with the blue navy on top of the red orange and vice versa as shown.
With the blue "on top" draw a diagonal line from top left corner to bottom right consistently

5. Sew quarter inch on either side of the drawn line, cut apart on the drawn line
 and press towards the larger blue piece. 

6. This results in 2 sets of four
mirror imaged triangle umits.

7, Sew into counter changed pairs, pressing
towards the larger blue piece and then
combine the pairs but don't press yet.

8. This shows the centre of the block where
 the seams cross.

9. Unpick the stitches in the seam
 allowance on both sides of  the block.

10. Now you can press the seams in an
anti-clockwise direction on the back and clockwise on the
front so all the seams will nest when the blocks are sewn
together. The centre will also lie flatter.

There is no reason why you can't introduce a third or fourth colour as long as you keep to the same colour groups.

  Here I used two different orange/red strips making three colours. Yet to do four .