Make your own spray baste glue
I am in the process of string piecing a bunch of quilt blocks, and I decided to use up some scrap batting to make the blocks. I glued the batting to the backing, and this is the glue I used.
Boil 3 cups water, add 1/2 tsp salt. Reduce heat to medium, whisk 3 Tbsp flour into the water, a pinch at a time. Continue whisking to break up the flour, and cook until it thickens to a consistency of egg white, or maybe gravy.
Cool to room temperature.
Fill a clean spray bottle 1/4 full of rubbing alcohol. Add water/flour to fill the bottle, leaving a little room to shake. Cap it. Shake well before each use.
I don't know how big your spray bottle will be, that's why I tell you to use 1 part rubbing alcohol to 3 parts water/flour.
This glue is wonderful for QAYG blocks. I cut my backing, lay my batting, lift the batting 1/2 way, spray the glue lay the batting back down onto the backing, and do the same to the other half of the block. When it's dry I can gently shake the backing/batting block and it stays glued. I am able to lay my top and quilt it on the machine. I Don't Know if it would work on a bigger quilt.