Well, after all my questions about corking my old screw top bottles, I had a brainwave...
The bottle bank in the municipal car-park near the top of our street rarely if ever has the lids locked, so I took a load of our glass for recycling and came back with 20+ (formally corked) wine bottles!
I've soaked them in hot water and found a massive difference in the glue used on the labels:
Some floated off
Some peeled off easily
Some scrubbed off with a little effort
Then therere the others
The ones where the glue outright refuses to come off, no mater how hot the water and no matter how hard I scrub.
Anyone have any tips for getting the awkward label-glue off of the bottles?
I use inexpensive ammonia. Less than a dollar a bottle. I put about 1/2 cup in a small plastic bag sitting in a plastic bowl/bucket. Lay the bottle in the ammonia label side down and it falls off in about 15 minutes. No scrubbing required. Another method is to dillute a cup or two of ammonia in water in a 5 gallon bucket. Submerge as many bottles in there that you can and let it sit a day or so. Labels fall off.