Originally Posted by
bearisgray
The triangle in a square angles (Doreen Speckmann's Peaky and Spike unit) are easy to draft, but the angles in the center triangle are approximately 58.3, 58.3, and 63.4 degrees, and the angles in the skinny side triangles are approximately 31.7, 90.0. and 58.3 degrees. There are many rulers available for this, also.
So - the 45, 67.5, 67.5 (8-sided "spiderweb" ruler) nor a ruler with 60-60-60 (equilateral triangle) will not work for that unit.
The difference is the equilateral triangle has 3 equal sides, and an isosceles triangle the base is smaller than the sides. That's what I call a V block.
Once again, that graph site I like can come to the rescue as well!
https://www.incompetech.com/graphpaper/
This is where I prepared my fabric for a one block wonder sort of thing. I prefer to carefully stack my fabric and baste it and then cut through. I had meant for these to be hexes and didn't realize until after I started cutting that things weren't working out the way I wanted them to. It isn't that they are bad, but they are the wrong shape for what I wanted to do and used up the fabric I wanted to use. I have other fabric, and now I have these to figure out what to do with! All because I grabbed the wrong triangle.