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4.5 Inch Bloc-Loc Half Square Triangle Trimming Ruler

If you're looking for a way to make your Half Square Triangles perfect each and every time...look no further!  This very unique and revolutionary ruler is at the "cutting edge" of today's trimming rulers!!

Notice the channel in the center of the ruler.  It accommodates your seam allowance so the ruler doesn't rock or slide, and "locks in" position for a perfect trim every time!!  It's the best Half Square Triangle trimming ruler....Bar None!!!

Two rotations and your block is trimmed to perfection.  Make your Half Square Triangles larger than needed using the method of your choice, and trim them with this ruler.  This 4.5 inch ruler will trim any Half Square Triangle from 4.5 inches to 1/2 inch!!  (If you need a larger ruler, I also sell the 6.5 ruler and a combination pack of three rulers: 2.5, 4.5 & 6.5) 

My Heartspun Quilts Hints book is the perfect companion for this ruler as it has sizing tables for making your Half Square Triangles larger from 1 inch to 12 inches in 1/8th inch increments, with full instructions on piecing and trimming!!  Click here to read more about my Hints, Tips and Tricks book!

If ordering outside of the U.S. please email me and I will send you a PayPal invoice for the pattern and appropriate postage.

If any notion item is out-of-stock and you'd like to order one, please email me at, and I'll be glad to order it for you.

Please be aware that all sales are final.