6 1/2 三角形正方形向上 PLUS by Quilt in a Day

The tip grooves on this ruler grab the fabric so nothing shifts while I trim, which fixed my wobbly corners instantly. I squared up a whole stack of half triangle squares in one evening instead of a weekend. My blocks finally line up when I sew them together.

I used to dread trimming HSTs because mine always came out slightly off. This ruler squared up a whole stack of quarter triangle squares in one evening, and the tip grooves kept my rotary cutter right where it needed to be. Half the time, exactly like it says.

Cut my half-square triangle trimming time way down, and the 6 1/2" size lines up exactly with the squares I usually chain-piece. The tip grooves let me line up the points without marking anything first, which is the part I always dreaded.