Add a quilt backing to hide stitches?
On the front of the quilt I used several different shades of thread to quilt the various blocks; also using different techniques like stippling, outlining, cross-hatching, waves, etc.
I had used a muslin backing since it was going to be a wallvhanging. Now, I've changed my mind and want to use it as a throw so the backing looks awful as it is, with all different color threads going every which way (but loose!).
So my question is: could I now put on a SECOND backing and quilt it from the front by ditch stitching the main seams in one color, probably an invisible thread, so that the new backing is attached to the front? Or is there a better way to put on a new backing?
Oh, good golly! This brings me back to the very beginning of my quilting days, back in New Jersey at a store called Fabricland on Hwy 22.
I sat in my first quilt lecture with a gal by the name of Shirley Botsford (who has created quilt patterns for the Simplicity pattern company and written a book on quilting with "Daddy's ties").
What you've described is
what she recommended!
As you said, you'll need to do some quilting to hold the new backing to the already quilted quilt. Be mindful to add enough quilting stitches. As a throw, if it's anything like my house, it'll get washed more than my regular bed quilts. You'll want to have enough stitching for it to go through the washing machine.
Lifting a quilt when it's wet puts a lot of stress on the seams. While the quilting you've already done will hold the batting together nicely, these new stitches will feel the stress as you life the quilt out of the washer.
I'm in agreement on the monofilament thread for the needle, then match the value of the cotton bobbin thread to whatever fabric you're using for the new backing.
The ditch quilting will remain hidden, so as long as you don't rat yourself out, no one will ever know!
Good job thinking through the problem! You should be proud of yourself!