I am a fan of the Creative Grids 4 in 1 Triangle ruler. In addition to being able to square closed (like the quilt in a day or the perfect slotted trimmer) it will allow you to strip piece those hsts. There is a method that lets you do them to perfect on the first cuts - no trimming!...you end up with a bias edge. (Hey nothing is perfect!) I prefer to precut and then use as leaders and enders - no bias edges. Great way to use up that last 9" of fabric into hst scrap blocks - rather than add to the scrap pile. Yes they sometimes get wonky but I'm not a Everything Must Be Perfect quilter.
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