This weekend, I showed a customer and friend at the shop where I work how to use the tool for her binding. She wished she had pictures to refer to so she could refresh her memory next time. OK then, it's time to finally write that post! Mary M., this one's for you!
For completeness, I am going to include the entire process of attaching the binding to the front of the quilt. I use double fold binding made with 2 1/4" strips, and use a 1/4" seam allowance when sewing it on. See this post for instructions to make double fold binding from individual strips, or this one to make continuous bias binding.
I lay one end of the binding about halfway along one side of the quilt, matching the raw edges of the binding with the raw edge of the quilt, and spread the binding to the corner, laying it flat and being careful not to stretch it, and pin it in place.
At the corner, I measure and mark the binding 1/4" in from the edge of the quilt.
I start sewing about 8" from the end of the binding strip, leaving a loose tail...
...and stop sewing with the needle down when I reach the mark I made on the binding near the corner.
With the needle down, I raise the presser foot and pivot 45 degrees so I can sew into the corner of the quilt.
To take the binding around the corner, I fold the loose binding back at a right angle to the binding that has been sewn. There will be a 45 degree fold in the binding, lined up with that line of stitching into the corner. The stitching helps guide the fold.
I finger press that fold before bringing the loose binding back in line with the next side of the quilt.
After I line the binding up with the side of the quilt, there is a straight fold lined up with the edge of the quilt that already has binding attached. I pin that in place.
I continue laying down binding without stretching, pinning as I go and marking the next corner before stitching this side down as well. I start stitching at the fold/previous edge, fixing stitches or backstitching a few stitches to secure the seam, and again stop and pivot at the next corner.
I keep going until I come back to the side I started on. I go around the corner and continue sewing on binding until the stitching is about 12" away from where I initially started stitching the binding.The binding tails on both ends of the binding will overlap.
To determine where to trim each binding tail so their joined length will just fill the gap, I fold the first tail back on itself about 2". I fold the second tail back on itself so the the fold is flush with the fold in the first tail.
I finger press the folds to mark them well, then unfold the binding and mark the spot on each tail where the fold lines cross.
Next I mark a second point on one tail, 1/2" further out towards the end of the binding strip. This adds enough overlap with the other tail to allow for a 1/4" seam allowance. This second point is the one that matters.
This is where the corner trimming tool comes in.
Without twisting the binding strip, I smooth it open and position the trimming tool as shown below, with one short side flush with the bottom edge of the binding strip and the long edge cutting through the marked dot.
I swing this down onto the cutting mat, readjust the tool position as needed, and trim off the binding tail, as well as the point of the angled cut, using the blunt point of the tool as a guide to trim the tip.
To trim the other tail, I smooth it open without twisting...
... rotate the tool 180 degrees and position it so the long side runs through the dot closest to the end of the tail. (That's the second dot I marked on the tail earlier, not the one that runs through the intersection of the folds.) Note that the pointy tip of the cut will be on the top edge of the strip, whereas the pointy tip of the other tail was on the bottom. (These can be reversed, as long as they are opposite each other things will work out)
I can check that I have the tool positioned properly by folding the strip back against the tool. If things look like this...
...the two tails ends won't meet properly so I know the tool is not positioned properly.
If it looks like this...
...all is well and I can swing the tail and the tool to the cutting mat to trim the angle and the point.
Now both tails should be trimmed at the same angle in the same direction.
Why did I trim the points? Those trimmed points show me exactly how to line up the tails to keep my binding straight.
When I bring those two angled edges together with right sides facing, each blunt tip will line up with the edge of the other strip.
When I sew with a 1/4" seam, the strips will line up perfectly.
I finger press the seam open, fold the binding in half so that all the raw edges are aligned again, and sew it all to the edge of the quilt, overlapping any previous seam by several stitches
The seam where the binding ends are joined looks just like the seams in the rest of the binding.
This process works like a charm for me. I haven't twisted my binding a single time since I started joining my ends this way.
Of course, the next step is to turn the folded edge of the binding to the back of the quilt and stitch it down. In the past I always stitched that part by hand, but recently I have been pressed for time so I have been practicing doing it by machine. Come back Friday to see the process that I find works best for me for machine binding.