My wife got her boss an awesome bottle of Knobel Rickhouse whiskey for their Christmas party this year, and I had to find a way to make it interesting. I'd already printed a bunch of really annoying gift card boxes and wanted to find a way to integrate those in to it.

The idea struck me to put a locking collar on the bottle, and hide the combination inside the annoying box. Problem was, I couldn't find a collar that would fit because the bottle has some odd dimensions.

SO… I made one 😁

Because of those dimensions the lip to retain the collar is very small. The locking hole is ∅5.1mm, so most common luggage locks will fit it just fine. We picked up a Master Lock 647D for a few bucks at the store and it's a perfect fit. There's an internal chamfer on the lid so if you were lucky enough to get one of the signed closures it won't rub off the autograph.

Available either as a print-in-place (only one small support) or as two separate parts (more supports). PiP version prints fine although there is some scuffing on the inside of the lock clasp. They are separate plates in the print profile. Line widths and speeds are all configured to print this as the most continuous lines possible with an even surface finish. Durable materials are suggested, I just used eSUN PLA+ since that's what I had loaded.

WHAT YOU'LL NEED

• heavy duty paper clip (∅1-1.5mm)
• heat source (lighter and screwdriver, soldering iron, etc)
• the prime line off your print bed
• a hobby knife

Start by straightening out and cutting 46-48mm off the paper clip.

Use the left over paper clip to jam it down all the way in the hole.

Fold up your prime line twice (four or five layers thick) and jam it down in the hole.

Cut that off flush and then fuse the surface together. I happened to have an M3 heat insert tip on my soldering iron and it made the job super easy.

That's it, you're done!