Drink Can Wind Mobile - Cutting Tool

I first noticed these Drinks-Can-Wind-Mobiles when in Hong Kong, and was somewhat blown-away by how elegant their design was. I think they are part decorative, but also I suspect keep birds away from crops. They were from a place in Tai O, and island, known for it's laid back, slow pace, dried fish products, and cool crabs and mud skippers. In contrast to the bustle of Hong Kong island metropolis, it is indeed the sort of place people have time to craft things like this and have space to appreciate them.

However, I never met anyone nearby who could tell me how to make them, so I had a go at trying to figure it out myself... I should be said that these cuts can be made with a steady hand, but as I wanted my young son to have a go also - I felt that a 'guide' for the blade would be wise.

So I created a tool to help make it a bit safer. Hope you find it useful also!

You will need:

Aluminium Drinks Cans (330ml).

Access to a 3D Printer (see STL and Solid Works files below). Print at standard settings (design is not 'fussy').

Wire (about 1-1.5mm thick).

Scrap Wood (e.g. 18mm Plywood).

Basic tools: Craft Knife/Scalpel, Small Drill (to allow wire to thread through), Pliers.

Also Required (not shown): Masking Tape, Sharpie Marker. Countersunk Screws (~15mm long) & Screwdriver.

In case you're curious - I tried cutting into the can by hand, (Fanta Orange can), and found this was tricky and was very hard to achieve a clean line!

I realised I needed a 'guide' for the blade, so I actually made 3 version of this type of approach, with small tweaks, such as adding 'viewing windows' (so as to see the marks), and a 'centre point hole' for the drill to hit the centre of the can. I considered removing more material (like swiss cheese) but there is a trade off in that this will likely snag the rotating metal, and also print quality can be more tricky, and needs support. Either way - feel free to iterate on it.

Perhaps the most impactful 'update' was to make it so the tool could be screwed to a piece of wood - making it more stable, and reducing risk of slipping with a knife.

The third picture also shows a very early attempt to wonder if I could 'push cut' a can, with a scalpel blade protruding. The hope that I could do say 15 incisions in one 'punch' through. But alas, the forces were too high even for one. So I left it as a 'one cut at a time' level...but perhaps I'll have a new idea / someone comments to inspire a new direction!

And finally, I eventually figured out what the good folks at Hong Kong already knew - which is that rather than *cut*, it's better to *score*, and then flex to fatigue the metal, and then it separates, with a very good clean edge.

Ironically, the locals likely just 'score' and do it freehand, but I think the 'Guide' I create, is a useful tool, not just for me, but also for my young son to join in!

I put this print on standard settings on an Ender 3. It took 4.5 hours, on a 0.6mm nozzle. In hindsight it could have been done much quicker with a 1.0 nozzle. I didn't find it needed support material. I used Recycled PLA.

I've made holes for countersunk screws. Screw to some scrap wood as shown.

You can mark-up your can as shown with a bit of Masking Tape. I found that 1cm marks worked fine, and just went round the can nicely, with even spacing. You need not do this every time...

...If you get the spacing just so, you can use the 'window' to guide you. Simply add a small 'index mark'.

So you 'cut' and then, rotate, so the cut indexes with that mark.

Cut, Rotate to index, and repeat - all the way round.

Try to be accurate, as if not, you'll get a 'cumulative error' and it will not be perfectly spaced. Or you can just use the tape if in doubt. Whatever works!

Using a Craft Knife or Scalpel, cut as shown, using the guide-slot like a ruler to give a straight line.

As with the 'index' method, you can also add two marks at the top and bottom to let you know where to start and stop the cut/score.

In hindsight you might want to do this first, as it's better than forgotting!

Use the 'guide' to centre the drill bit, and drill bottom and top as shown.

If you're using the Cut method (ie cutting right through using fair force), then the can will be all cut.

However, if you're scoring, you need to remove and 'flex' to 'fatigues' the metal so it breaks along the line you scored.

Do this by carefully pressing/pinching near the score line, and you'll find it'll eventually split. So this all the way round the can. Take care as this can be sharp, as it's very thin metal, so wear gloves if you prefer.

It may look a bit crumpled at this stage, but don't worry - it'll 'straighten out' in later steps...

Insert the pliers and add a crimp as shown. Do this all the way around, at a slight angle.

This 'angle' is what makes the wind have a pressure to rotate one way and not the other.

NOTE - reverse the crimp, on the other side, so you have both crimps facing the same 'focal point' if you like.

To give the 'blades' a bit of angle, press the can, to flex them outwards.

If any bend inwards, carefully push them back out with your finger (careful!) or use pliers.

Thread the wire as shown, and ideally create a low-friction loop as shown at the base, so it does not snag.

Note - you may need to push the 'tab' inside out of the way, so it does not rub against the wire, slowing it down.

Bent a 'hook' in the top end of the wire, so you can hand it up.

This is ready to go!

You can of course make different cuts and angles.

Of course some of the HK ones have the blades also pushed inside!

See what variations work best. You can try different 'blade angles' and variations.

Thanks for any ideas or variations on this build. And do visit Hong Kong's Tai O...

...If you're curious I also did a report on UK and HK Repair Cafes:

https://www.rs-online.com/designspark/repair-cafe-culture-part-1-repair-like-your-life-and-career-depends-onit

Video: https://youtu.be/bdIQ6tGroSI

Thanks!

Jude

https://www.judepullen.com/

https://www.instagram.com/boredsmart/

https://www.linkedin.com/in/judepullen/