I've never tried the Elmers & water method. How much water to glue should I use; about half & half or what?

I would worry about the flour attracting bugs.

I use the glue straight, but I buy a gallon at a time and pour some in a condiment bottle from a picnic set. I just hold it high and swirl the glue all over aiming to leave glue about every four inches just like when I used to pin. I have never had any problem sewing through it when dry. Just so you know, some of the glue may show on the front or back, but a quick warm wash after quilting removes all of the glue. I do not think washing is allowed before most shows though...

Great info! I've used commercial basting spray in garment making and it's a mess and a huge pain to clean up. Elmer's sounds much better!

This glue is meant to be washed out as soon as the quilt is finished. All glue or flour is washed away. No bugs.

I use Elmer's all the time in joining ends of binding.

I pin-baste my quilts. There are a few things about the home-made basting spray that give cause for concern. First, the flour -- this almost certainly will leave a powdery (flour) residue in the works of my vintage machines, which I would not want. Plus, the recipe calls for "salt". Salt will almost certainly contribute to rust in my vintage machine(s). Finally, the video I saw shows the quilt basted with this home-made spray is so stiff, it would be impossible to fold or roll so it can be quilted on my vintage machine(s). These are issues I would be concerned about, and my suppositions may prove wrong. I would, however, want these issues resolved before I would even consider using such a basting spray. My main issue with sandwiching a quilt is the room to get the quilt sandwiched since my quilts have been rather large (a little larger than king-sized). I have back issues (including 4 spinal surgeries) which make working on the floor impossible, and my table, though large, is not large enough. I realize, of course, that these are my problems, but others may also have the same problems.

My thought? Penny wise, pound foolish.

Flour can draw bugs as well as cause mold when mixed with water - which is why people stopped using it for wallpaper paste.
And any glue can mold.
If using either for quilt basting make sure to wash them when as you're done.

Yes, I use this recipe. It is a little bit to put together but it works and I do like it. I have had no issues with it not coming out in the wash or using it or smelling bad. It smells a bit like alcohol but not too much, I don't mind it a bit. I do think it sticks a little better if used with cotton batting. Pretty much I use 80/20 batting and I think it doesn't stick as well. Very happy, very pleased to have this on hand as it saves money by not using the 505 adhesive.