My first tries at cleaning glass with things at hand:
The glass all ready has smoothed off edges on both sides; it was done underwater in a bucket. This is a must do step not to be ignored to your peril. I got sliced up right away cleaning off emulsion.
1. Windex: Nope. Water beaded and did not run off in a sheet. Glass was laid on a paper towel and it moved all over the place. I had to hold it down or hold it in my hand. Not good. Water did not run off in a sheet; water beaded.
2. Dish soap, liquid type. Nope. Same results with the added annoyance of the glass moving even more in a too large tray. 4x5 glass needs to be in a 4x5 tray that is made for it.
3. Baking Soda. Nope. Scrubbed with a paper towel and a little water the results were just like the first two attempts.
4. Tide powdered detergent that is dermatalogically neutral. This worked pretty well. A brand new sponge was used that is rough on one side; both sides were used underwater in a 4x5 tray. Water ran off in a sheet. Tap water was used. Distilled water would be even better. After it drained a bit, standing up on a paper towel, it beaded. Perhaps it would be good enough with a distilled water rince.
5. Photo Flow: perfect. After a wash in Tide, a dip in a solution of Photo-flo in tap water a smooth sheet of water dried without any beading. Film negatives are given a dip in photo-flo so why not glass?
How will emulsion adhear? That is next, now that I have a working method to start with.