3D Print the Goonies Doubloon!

Hey you guys! My last instructable was making the Goonies treasure map. The next piece of the puzzle has to be the doubloon that goes with it, since it is drawn on the map and guides Mikey to the restaurant where the hunt for the rich stuff really begins. First, let's over-analyze the movie prop!

For a start, the Goonies doubloon is not really a doubloon. Doubloons were small, gold, and worth 32 reals, i.e. one doubloon was worth four ‘pieces of eight’. By contrast, the the Goonies doubloon is enormous and clearly not made of gold. It's not even based on a Spanish coin. The side seen in the film and illustrated on Willy’s map bears the shield found on English Tudor groats and crowns. The other side is never seen but is apparently based on a French Louis D’Or, with the date 1632 added to the prop (how One Eyed Willy managed to obtain a coin minted in the same year that he finished digging the tunnels and drawing the map is never explained, hmm!). The only Spanish thing about the Goonies doubloon is the lumpy ouline which is reminiscant of ‘cob’ coins crudely minted in the Spanish colonies of South America. Did the prop maker choose these designs just because they looked cool? Where they sculpted from scratch or adapted from coin moulds from some earlier production? We may never know.
EDIT: Since writing this instructable I discovered that Disneyland sold Pirates-of-the-Caribbean doubloon souvenirs in the 1960s/70s that look remarkably like the Goonies doubloon, complete with hole! The makers of the Goonies would have been the right age to have visited Disneyland as kids during the 1960s... I strongly suspect there is a link here!

The next thing to note is that more than one coin was used for the filming. There is the one handled by the actors -which seems to match the one pictured in the original fanzine- and another one that was used for the close-up. You can tell they are different by the shape of the holes; I'm guessing they were both cast from the same mould and the holes were filed out later. Replicas are available online, and slightly different versions pop up from time to time, but I haven't seen anyone document making their own, which surprises me. I therefore looked at lots of pictures and created my own model using Sketchup before 3D printing it. Now you can print your own Goonies doubloon, too!

Supplies

• 3D Printer;
• Superglue or acetone;
• Fine sandpaper;
• Candle or other flame;
• Paint

Step 1: Print It!

Download the .STL file and print it using your preferred settings. I used PLA and printed it 'fine' (0.1mm) with a skirt, which took about 4 hours.

The coin is printed in two halves, so after printing you need to glue them back-to-back with superglue or acetone, or whatever you prefer.

Edit January 2021: I have tweaked the model to make it more screen accurate. This file is called GooniesDoubloonVer2.stl.

Step 2: Deform It!

At this stage the 3D print is geometrically regular and has all those annoying printing layers. We need to smooth it and deform it to look more like the movie prop. If you print with ABS then you may be able to smooth the whole coin with acetone vapour, but I only have PLA which doesn't react that way to acetone.

What worked best for me was to hold a flame to the coin for 2 to 4 seconds so the PLA softens. This automatically rounds off some of the hard, fine details. In places where I wanted more deformation I held it over the flame, then removed it and quickly squeezed or smeared the hot plastic with my fingers. I was able to smooth out the rim of the coin, deform some details, and creat the 'smushed' areas this way.

Once the coin looks basically the way you want, you can go over everything with some fine sandpaper. You might want to use a needle file inside the holes or to tweak the rim of the coin.

Step 3: Paint It!

Finally the doubloon needs to be painted. The movie prop looks like aged copper, but you will find replicas in dirty silver or even gold, so the choice is yours. Everyone has their own preferred technique for painting, but here's what I did, using acrylics.

• Spray the coin with some primer (I used some really cheap car primer from the pound shop);
• When the primer is dry, give it a dark brown undercoat all over. I mixed in some black here and there so it wasn't the same shade everywhere. You can put it on quite thickly to hide the remains of the 3D printing layers;
• Next I mixed up some paint the colour of verdigris (copper oxide) -this can be anything from teal to pale green. Add water to create a thin wash and paint it liberally all over. It dries much darker, so I did this a couple of times using different shades of green and some white too;
• After I was happy with the oxiding effect I dry-brushed metallic copper all over, then finished with a lighter dry brush in gold to pick out the raised detail;
• Finally, coat it with matt varnish / clearcoat to seal it.

Hopefully you now have an authentic Goonies doubloon, now go find the lighthouse, the rock and the restaurant!*

*Ever wondered why he says "lighthouse" when it's clearly just a rock? In the original screenplay the restaurant was going to be a lighthouse, and the set even had what looks like a ruined tower. In the final script this was changed to be just a restaurant, but Tillamook Rock has a real lighthouse on it and is visible (in theory) from the restaurant set location -it's even mentioned on Willy's map. But for the looking-through-the-holes-in-the-doubloon scene the film makers ended up using a picture of Haystack rock and its neighbour (no lighthouse), maybe because they're closer to the shore and are very striking.