One aspect of teaching that I enjoy is learning about new quilting tools from my students. When I taught recently at Quilters on the Rock, Whidbey Island, a lady had a plastic gadget to gauge precise seam allowances. An accurate 1/4″ seam allowance is very important especially when pieced sections of blocks are joined to non-pieced sections. If the seam allowances are off by even a tiny fraction, the error is compounded with multiple seams and can cause serious piecing problems.
This little gem is made by Bonnie Hunter and included as a freebie if you purchase one of her books. However, if you go to her website, you can order these in quantities of six ($24 for a six pack). The seam guide is easy to use and it works! Simply place the machine needle through the appropriate hole with the plastic aligned squarely on your machine bed. Then position tape along the edge and remove the gadget. Butt the raw edges of your fabric against the edge of the tape as you sew and you will have a perfect seam allowance.