Illusionist Locket: a How To.

Last Christmas, I decided to make my girlfriend the locket from the Illusionist ..For those of you who haven't seen exactly what this locket is, here is a scene from the movie http://www.youtube.com/watch?v=nvKWNyp5bbI ... As far as i know, in the movie, they used two lockets and didn't actually make a working one.
As you can imagine, after some people saw this cool locket, they wanted to make a working one, myself included.
The first thing I did after I decided to make the locket was to have a quick google search.
one of the most usefull links I found was http://cranitorium.com/aneurysm/index.php?Itemid=50&id=20&option=com_content&task=view..... and from instructales user Pushan Panda (https://www.instructables.com/id/Illusionist-Heart-Locket/).

I wanted to make it more than a plain locket, to have some detail in the front and back surface so that it was visually more appealing.
With this in mind, I started looking up veneers. I then had the idea of making the front and back surface from two separate materials so there was a full depth inlay.

I came up with a few designs for the front, from the butterfly seen in the movie to stars and horse shoes. In the end, I decided to go with a stylised A (her first initial) and used a Celtic script ( I'm Irish :P )

If you like this instructable, please vote for it in the holiday gift competition and in the instructable design contest. Thank you!! :D

Here is a video of my locket:

Note: I have made two of these now. A replacement was made and some of the things learned from the first attempt were applied here. This means that images from both lockets are used, but they were the exact same so no biggie. Thanks to Anna for recording the video.

Step 1: Bill of Materials and Equipment

So, when I made the locket, I had access to a laser cutter in a local school. This doesn't mean this can't be done without one though!!!! If you have a scroll saw, you could manage this project with some patience and some fresh blades. I used a scroll saw to make a larger scale one before I made the actual one and it should be no problem to do.
Anyway, here is the list of equipment:

• Sand paper ( some fine, medium and coarse grades)
• Laser cutter or Scroll saw,
• Scalper with good blades,
• Good tweezers,
• Glue ( I used super thin model aircraft super-glue but regular super-glue will do too..any strong glue that adheres well to wood and acrylic should do)
• Glue remover( for your fingers :P)
• Fine drill bit(same diameter as magnets)
• Pin vice for drill bit ( can use drill but be carefull!!!)
• Table saw or bandsaw
• Needle nose pliers
• Drill or lathe( wood lathe is fine)
• Fret saw (makes life easier)
• Jewelers files (optional)

Warning!!!
Please, do not use any tools that you are unfamiliar with!! Ask for help!! Some of these tools can be very dangerous and should be treated with care. I take no responsibilities for any injuries sustained in the process manufacturing this locket. You've been warned....

Materials:

• 3mm Arcylic( don't need much but may need to make a few test pieces, 100mm x 100mm should be enough)
• Your wood of choice. Pick one that'll look good and has a nice grain. I used walnut. (again, you may need bits for testing so minimum 40mm x 40 mm x 100mm block
• Wooden dowel for the split pin approx 10mm diameter but it'll be reduced later.
• Varnish + brush( I used Ronseal Ultra Tough Satin Coat, Clear)
• Some strong wire to make the loop to attach the chain ( I used some AL brazing wire)
• Small magnets( to keep the locket locked in either configuration, improves rigidity) mine were 1.5mm neodymium cubes .....you need around a dozen
• A dress maker pin with a small round ball at one end(around 2-3mm diameter) use a good one

Step 2: Designing the Locket.

Okay, so, first of all, you need to design your locket. I've included my drawing but you'll probably want to change the front and back to whatever you want. For people using a scroll saw, you might want to change the shape of the picture recess for ease of manufacture.

The biggest thing to remember when you are designing all this is the thickness of the blade/laser that you are using. This really only applied to the inlay pieces in the top and bottom parts. With the scroll saw, this is easier to take into account because the blade it vertical.
However, the laser I had access to wasn't  focussed properly so the cuts were diamond shaped rather than parallel.

To counter this problem, it it occurs for you, make a mirrored copy of the inlay and scale it accordingly so it fits. It might take a few goes to get it right but it'll be worth it.

Note, the drawing here has the ball of the pin on the bottom piece but later pictures show it in the top piece. This drawing was created after the fact and the doesn't matter which side the ball is on. Sorry for that confusion.

UPDATE:
I've attached the CAD files(solidworks and STL) for anyone who want's to try print it on a 3d printer. If you succeed, lemme know :)

Step 3: Making the Layers

The first thing you need to do with your block of wood it to square it up. Or rectangular, just so long as two adjoining side are flat and 90 degrees apart.

Once it's squared,set the fence on your table saw or bandsaw to 3mm( the height of each layer ) or to what ever thickness acrylic you have.

Please mind your fingers!!! These machines will have no problem removing fingers or hands!!

Feed the wood the along the fence and cut the strips out.  When it's getting near the end of each strip, use a shaped piece of wood to feed the last of the wood through. You will need 4 strips but make more to practice with.

If any of the surfaces are rough, give then a quick sanding with some fine grit sand paper

Step 4: Cutting the Design

Laser:

1. Load the design files into whatever software package you are using, or use the included 2d editor to draw the parts.
2. Place a layer in the laser, setting what ever you need to set and make a test cut.
3. Try reduce the amount of burning to the wood, it just makes cleaning the burn marks easier.
4. When you're happy, cut out all the wooden parts. Note!!!! on layer three, only raster/draw the pin's location on the surface of the wood, don't cut it.......I speak from experience :P 
5. Now repeat with the acrylic design. this you will possibly have to iterate through it ( resizing it) a couple of times to get a perfect fit, Leave the wood the same and just alter the acrylic, or vice versa, just keep one the same.
6. once you're happy with the fit, move onto the next stage

Don't look directly at the laser. Yes, it is bright....

Scroll saw:

1. Mount the printouts on the wooden layers
2. Carefully cut out each layer. Be patient!! Don't press on the blade too hard and keep a good hold of the work.
3. Clean up any rough edges with medium sandpaper
4. Repeat 1-3 with the acrylic this time. Be carefull with the acrylic and take it nice and handy.
5. If your fit is just a little bit off, don't use the saw to fix it!! grab some sandpaper and sand off whatever need removing.
6. Using a scalpel, cut though on layer 3 where the lines are.

Watch you finger here too......

Step 5: Gluing the Insert

The first thing I did was to assemble the front and back sections.

1. Before any glue was applied, I gave all the edges to be glued a very light sanding with fine sandpaper to remove any burrs or carbon left from the laser.
2. Do a dry fit just to make sure it all fits. (first image)
3. I then glued both parts that were going to be in contact and set them together, making sure to keep the insert level with the surface of the wood.( note: don't glue the two halved together!!)
4. Keep repeating the process until the two parts of the front and the back are assembled. Try not to mix them up.

Step 6: Making the Loop for the Chain

1. Take the fine brazing rod and bend it into a U shape with two longish legs..leave it attached to the brazing rod for ease of handling.
2. Next, bend the legs of the U down more than 90 degrees.say 100-110 degrees. This give the loop extra purchase in the wood and make's it much harder to it to be pulled out.
3. Mark the position for the holes in the third layer of the upper portion (top right) and drill with the right size bit at the correct angle.
4. Now carve out a channel from the hole's to edge of the wood for the loop to sit in.
5. Sit the loop in the wood, making any adjustments necessary. Cut/ file off any of the loop that protrudes from the bottom of the layer.

Step 7: The Middle Layers

Starting with layer 3,

1. Score along the line of the pin, carving a small channel for the pin to sit in.
2. You can use the small drill bit to help carve out the small recess for the ball. Use the scalpel to give it a good round shape.
3. Take the pin and bend it where it need to be bent, then snip off what ever is excess.
4. Place the correct layer 2 piece their respective layer 3 pieces and mark where the small channel is on the layer two parts.
5. Repeat 1 and 2 until the pin can sit in it correct position and the layers can sit complete flat on one another.  Try to keep the pin as tight as possible.
6. You can glue layer 2 and 3 on the ball side , making sure not to glue the ball itself. be careful with the edge that goes over the chain loop, it can be delicate.

Step 8: Making the Split Pin

For this step, ideally you have access to a wood lathe or even a drill. 
Lathe:

1. Place a small length of dowel in the lathe, making sure it's well attached and the tool rest is in the correct position.
2. Turn on the lathe and reduce a 15-20mm section of dowel to 7mm diameter.
3. At the centre of this section, mark a line and then reduce one side to 5mm diameter.
4. Remove from the lathe and remove the excess above the 5mm end only!!!! If you cut the 7 mm end too, the next step'll be really fiddly and hard. Also make sure you have at least 6mm of 5mm dowel lefts.

Drill :

1. Place the small length of dowel in the drill and tighten the chuck up well.
2. Using a file/rasp/coarse sandpaper, reduce the last 15mm or so to 7mm diameter.
3. Now reduce the last 6-7mm or so to 5mm diameter.

Splitting the pin (same for drill and lathe):

1. Place the reduced dowel in a vice.
2. Using a fine fret saw or scalpel, cut straight down the middle so that both halves are equal. Be patient and line it up well.
3. Once you've cut down through the 7mm section,cut the top top part off so that you have a layer thickness of 7mm dowel and 2 thicknesses of 5mm.
4. Verify that the split pins fit in their space in the locket and that they can rotate the whole way around when the locket is in the heart configuration.
5. When you are happy with the fit, mark where the 5mm section where the layer 2 surface is. Don't cut yet.

Step 9: Magnets!!

I'd seen magnets used in one or two of the lockets online, so I decided to put some into mine. I bought a bag of 50 1mm x 1mm x 1mm rare earth magnets from ebay ( can't find the exact page but these will do just as well http://www.supermagnete.de/eng/W-01-N for Europe and  http://www.supermagnetman.net/index.php?cPath=29  for the US) Cylindrical ones will do just as well

Anyway:

1. Decide where you want the magnets. I have placed a pair in the split pin, some around the rotating pin, in the side of the lid and between the lids and the adjoining layer.
2. Carefully mark where the first magnet should go. 
3. When you are happy with your marking, sure the small drill bit (1mm) to create the recess. The hole should make a tight fit with the magnet.
4. Mark where the corresponding magnet hole should go.This need to be precise as if they are misaligned, the magnets could pull your locket off angle.
5. Now the finicky part. Glue one magnet into it's recess, keeping it parallel to the axis of the layers and let it dry....The allow another magnet to attach to it to determine the polarity. 
6. Mark the unattracted end and make sure that this end is the one that goes into the recess. If these magnets have to mate with other magnets, repeat the procedure. 
7. Repeat the process till you have all the magnets you want in.

You want to be really careful about the polarity because once those magnets are in, they aren't going to come out again. If one does go in the wrong way, you don't have much choice but to carve out a plug of wood to excavate it, and fill the void with filler.

Step 10: Final Assembly and Gluing

Continuing with the split pins:

1. You need to leave a peg on the top of the pin so that you can get a good mechanical bond with the top/bottom layer.
2. Leave a 2mm rectangular peg like that in the CAD drawing. Remove the rest of the material.
3. Reduce the the height of the peg to 2/3 the thickness of a layer.
4. Mark on the top/bottom layer where the recess needs to be to receive the peg. a good alignment is very important.
5. Carve out the recess and test fit the peg in the slot. The split pin should be able to stay in by itself.Test the assembly in the locket to make sure of the fit.
6. Once you are happy with the fit, glue the split pin the top/bottom layer.

Now glue the lower layer 2 piece to the lower layer 3 piece, making sure that the rotating pin is sitting in it's recess and that all the magnets are lining up. As the glue dries, rotate the locket to make sure it doesn't get stuck.

The magnets give the locket a nice clicky feel and let it stay in either shape.

Assemble the locket and test it :D  it anything sticks, just sand the offending area.
 When you are happy with the mechanics of the locket , sand the entire outside of the locket, removing the edges and  making the entire body smooth. occasionally test the locket to make sure you haven't removed too much material. Start with a coarse sand paper but quickly move through the grade till you are using a fine paper.

Step 11: Varnish and Finished!!!!

Disassemble the locket and crack out the varnish!! Do this in a ventilated or open area

1. Work out some way of mounting pieces so that all their surfaces can be varnished. I hung the body of the locket and used " helping hands" to hold the split pin pieces.
2. For the first layer of varnish, varnish all the surfaces, including the rotating surfaces, just so that everything is sealed.
3. The first layer can take a long time (24h) to dry, but successive layers take much less time
4. For subsequent layers, varnish all the external facing surfaces, including the picture recess.
5. You should apply at least 3-4 layers to get a nice strong protective coating.

When all the varnish has dried, and the solvent  smell gone, re assemble the locket. A second ring can be soldered around the loop to take the chain. You can solder this shut for extra strength.

Either you or the receiver can place the picture in the locket, just remember that it needs to be split for the mechanism to still work.

Place the locket on a chain, box it , wrap it and give it to whomever you please. Watch the growing delight on their face as they see the locket rotate and the lid slides over to reveal the cavity.

Good luck !!! 

Step 12: Video of the Locket in Operation.