My inspiration was some old folk art puzzle bottles a great, great uncle of mine used to make. It's the one on the left in the photo below. It was made in 1962, the same year I was born. I recently became obsessed with making one of my own and the result is on the right.
I chose to go with a wooden dowel with a bolt and nut through it because it gives more of a "how the hell did they do that?" feel than just the piece of wood stuck in a slot like Uncle Charlie's had. It's fairly easy to figure out how he did that.
Unfortunately, the only bottle I had around today was a Rumple Minze peppermint schnapps bottle and it has a textured finish to it. It's pretty easy to see in the bottle in person, but photos make the bolt and nut hard to see:
Here's how to make one if anybody's interested.
You need a bottle, a piece of dowel rod that's slightly smaller than the opening of the bottle and a bolt that is about half the width of the bottle. Use a new bolt and nut. The dowel rod, while required to be smaller than the opening of the bottle, must be big enough in diameter that you can drill the bolt-sized hole through it. I don't have any measurements or sizes on the wood or bolt I used: I just winged it.
Cut your dowel long enough that it sticks out of the bottle an inch or so. I put a knob on mine, but you don't have to. Drill a hole about 1/4 of the way up from the bottom of the rod. The hole should be slightly smaller than the diameter of the bolt you want to use and the bolt should be snug enough in the hole that if you turn the dowel with the bolt head pointing down, it won't slip and fall out of the hole.
Lay the bottle on its side and drop in the bolt and nut. Here's where things get tricky. You need a suitable magnet. I used one of those floor sweeper magnets about a foot long.
Tilt the bottle so the bolt is standing on end, on its head against the bottom of the bottle. You then need to manipulate the magnet so the bolt stays on end, but you need to slide it down to about the middle of the bottle. At this point, you can manipulate the hole in the dowel rod over the threaded end of the bolt and push down enough to get the bolt started through the hole in the dowel rod. Pull it up toward the neck of the bottle and use the skinnier part of the bottle to push the bolt through the dowel as far as you can and so there are threads showing on the other side.
With the bolt through the dowel, jiggle your nut around so it's lying flat against the glass, then put your magnet under the nut so it holds it in place. Then, simultaneously rotate the bottle and magnet so that the magnet winds up on top of the bottle, holding the nut above the bolt. At this point, you have to manipulate the dowel rod and bolt until you can get it right under the nut and in the center of it. Once you have the nut sitting on the bolt, you can remove the magnet and carefully hold the bottle and dowel as not to dislodge it. You will wind up with the nut sitting loosely, unthreaded, on top of the bolt.
Now the trick to the whole thing and the reason you have to use a new bolt and nut with a nut that turns very easily. While keeping the nut perched on the bolt, you have to start lightly rapping/tapping the dowel rod. I used my fingernails. As the rod and bolt vibrate, gravity will take over and the vibration will start to make the nut turn and move down the threads. Same reason they make Loctite, no? But, in this case, the nut will turn in a tightening direction instead of a loosening direction.
Just keep rapping the dowel until the nut is fully threaded on the bolt against it. The vibrations might also cause the bolt to slip through the hole, but you can just pull it up into the skinnier part of the bottle to push the head of the bolt back against the dowel.
Anyway, interesting little craft and something that will make everybody think about exactly how the hell you pulled it off: good conversation piece for the garage/shop.
Warning: This took me maybe an hour from start to finish. Half of that time was trying to get the bolt back out of the dowel rod when I realized I'd completed that part without putting the damned nut in the bottle, too. Put the bolt and nut in the bottle at the same time.
I should have remembered to sign and date the dowel rod like Uncle Charlie used to do.