The Triangles and Diamonds block is all about clean geometry and strong direction.

This tutorial introduces the Two Peaks in One ruler by Creative Grids, a specialty quilting tool that cuts two complementary shapes from fabric strips. The ruler's left side indicates your starting strip width, and the right side shows the finished size, with strips up to 6.5 inches wide supported. The first cutting function produces large triangles by aligning the ruler and rotating it down the strip; the second function cuts mirror-image companion pieces by folding the fabric in half before cutting, with a small notch on the ruler serving as a critical alignment guide for sewing. Together, the triangles and companion pieces form tall, peaked units that can be used as trees, geometric blocks, or half-rectangle triangles, making this a versatile and beginner-friendly ruler for a range of modern quilting projects.

Getting to Know the Two Peaks in One Ruler by Creative Grids

If you love working with specialty quilting rulers and templates, the Two Peaks in One by Creative Grids is one worth adding to your collection. Creative Grids consistently produces some of the most innovative tools in the quilting world -- their rulers and templates go far beyond standard geometry, making it feel like their design team is made up entirely of retired math teachers. This particular ruler has a distinctive shape and does double duty, cutting two different pieces to help you build beautiful geometric blocks.

Understanding the Ruler

The Two Peaks in One ruler is divided into two functional sides, and it is important to understand what each side does before you begin cutting.

The ruler can accommodate fabric strips up to 6.5 inches wide, finishing out to 5.5 inches. The left side of the ruler indicates what size strip of fabric you should start with. The right side shows your corresponding finished size. For example, if you start with a 5-inch strip, your finished pieces will measure 4.5 inches. It is a simple relationship, and once you understand it, cutting goes very quickly.

Cutting the Triangles

The first shape this ruler cuts is a large triangle.

Begin with your chosen strip of fabric. For this demonstration, a 5-inch strip was used.
Lay the ruler on the fabric, aligning the left side to your 5-inch line.
Slice along the edge of the ruler to cut your first triangle.
Rotate the ruler and cut the next triangle. Continue rotating and cutting down the length of the strip.

These triangles are versatile on their own. You can arrange them into a wide variety of geometric designs, or combine them with the second shape the ruler cuts.

Cutting the Companion Pieces

The second side of the ruler cuts the pieces that pair with the triangles to form a square unit. This side works similarly to the first, but there is one key difference: you will cut two pieces at the same time, and they will be mirror images of each other.

Take your 5-inch strip of fabric and fold it in half before cutting. This ensures you get both mirror-image pieces in a single pass.
Align the ruler to the 5-inch line on this side, just as you did for the triangles.
Slice off the angled end.
Pay close attention to the small notch at the top of the ruler. It is essential that you cut through this notch. This tiny detail serves as a registration mark to help you align your pieces accurately when sewing them together.

Sewing It All Together

When the triangle and its two companion pieces are sewn together, the result is a tall, narrow triangular unit that resembles a tree or mountain peak. You could easily add a fabric trunk and turn these into festive holiday trees, or leave them as is for a striking geometric look.

The companion pieces are also useful on their own. Paired with a contrasting background fabric, they create half rectangle triangles, which are endlessly useful in quilting projects.

Project Ideas

Here are a few examples of what you can make with this ruler:

A block-based design using the half-rectangle triangles paired with a print and a solid background
A bold geometric composition using the full triangles with added white accent pieces
An angular, graphic design that plays with movement and repetition across the quilt top

The Two Peaks in One ruler by Creative Grids is a fun, efficient tool that opens up many creative possibilities. Give it a try, and happy sewing!