Welcome to my Instructable! I'm going to show you how to make a locket, made out of coins. Now the whole concept of a "coin locket" is NOT mine BUT I came up with this particular design on my own. I'm sure there are finer ways to finish the project, like maybe better polishing and covering up the solder-blobs but I made it for my sweetheart and she likes the whole crude look of it!
It can be used as a pendant around your neck or a simple key-chain that's really up to you.
Step 1: Materials Required:
I had to use substitutes in a few places but I'll also mention the right thing to use wherever necessary.
1xBrass pipe I.D. 1.5-2cm (you can also use a brass sheet with a thickness of 0.5-0.75mm)
1x2mm HSS steel rod (it can be any steel. I found this one to be most useful because it doesn't bend when you hammer it)
2xBimetal coins(I used Bahrainian but you can use any. A Euro seems like a good idea but make sure they're all the same)
2xAny ordinary coin with MATCHING dimensions (I used a Dirham because the bimetal and the dirham were of the exact same size. You can even use 2 bimetals it's your choice)
Galvanized wire about a meter long to be safe (2mm. same as HSS rod)
1xBrass Chain with a small quick-release on one end.
-Fine-tip Permanent Marker
-drill bits 1mm and 2mm
-Tin/metallic sheet cutting scissors
-Pinning hammer (one with a rounded impact-face)
-Jeweler's steel block (for pinning)
-Dremel tool with sanding, grinding, polishing and cutting bits.
-Torch for brazing brass and a suitable flux and solder.
Step 2: Preparing the Coins.
Grab your reamer and a hammer and place the bimetal coin in the vice so as to make sure the center of the coin gets separated out easily and simply falls off. During this you need to make sure the vice doesn't open up too much else there will be marks left on the coin from the impact or you'll simply end up with a bent coin. To make sure the coin retains it's original configuration even after impact, you will need to knock the center out in one stroke of the hammer.
Once separated, we'll only be needing the surrounding brass ring and NOT the central portion.
Step 3: Cutting!
Next, grab your dremel and get to work. Remember, in order to protect the coins, ALWAYS place a folded piece of paper or any other such material so that the vice does not disfigure the designs on the coin.
For this I used a diamond-coated blade to make it easier and faster. It's also more precise. Basically, in this step, all you need to do is extend parallel tangents from the center as shown in the picture. Remember to mark exactly where they must be else it won't be as symmetrical and neat in the end.
Cut along the mark carefully and use the mini-file set to finish it off. Don't use power-tools as you get close to it as you risk grinding off too much.
Step 4: Drilling the Bimetallic Coins.
Next, set up the drill press with a 2mm drill bit and drill three holes as shown, which are equidistant from each other. Make sure you don't end up with an error because then you'll have to start over and repeat all the previous steps again. Also, I first marked the center of the holes I wanted to drill. Then I drilled in holes using a 1mm bit to make the job easier.
You'll need to stay in the center away from both the edges because if you don't, you'll end up with a weakened coin susceptible to edge-cracks during the pinning process. That'll look terrible so do a good job.
I used CA glue to first join the coins together and then drill them both together for added precision. You can soak the coins later in acetone to get rid of the CA glue.
Step 5: Preparing the Other Coins.
Okay so once you're done with the last step, which was drilling the bimetallic coins in three places, follow this step which requires you to place the recently drilled bimetallic coins on the ordinary coins and marking where the holes have been drilled so you don't make an error. This is crucial as the coins need to line up perfectly. After marking it, go about drilling the holes. I suggest you repeat the exact same steps again using CA glue for added precision.
In this step however, you will need to drill four holes, of which only two holes (as marked up in the picture) are drilled according to the bimetallic specs. Flatten the marked side using a file. Stop filing as you reach the bimetallic coin profile on the ordinary coin.
The two additional holes along the center will be required for the hinges so please get these right.
Step 6: Making the HINGES! (part 1)
Grab your brass tube and cut it open. I used a 5cm long section of it. After you cut it open lengthwise, using a hammer, using a light hand, simply straighten it up to form a flat sheet. I know this may not be the best of ways but hell, it works perfectly!
Next, use a bimetallic coin from earlier and trace the inner profile out, mainly the inner curvature as shown in the picture. Make sure to have an extension of material so you have extra to work with in case you make an error.
Using the pair of scissors, cut along the borders but don't cut along the curve just yet. Those come in much later.
Next, lock the piece in place in a vice and bend about 1cm perpendicular to the sheet as shown in the picture.
Then, take the piece of HSS 2mm rod and work the sheet around it to make it round. I also had to use a screwdriver to give it the perfect shape.
Repeat this for both the pieces and don't rush. It requires patience.
Step 7: Making the HINGES! (part 2)
Next, mark the center of the hinge as shown and the two ends that are supposed to be filed down. The reason I made the inner hinge first is because the outer hinges require more precision and attention, and to minimize the room for error, I worked my way out.
After the inner hinge is done, I use it as a reference to make the outer hinges.
Use a very fine file and remove any blurs as they'll obstruct free-motion of the hinge.
Step 8: Making the HINGES! (part 3)
Once the filing is done, grab your torch and start brazing. I first melted the flux onto the portion that needed to be soldered. Also, I proceeded with the brazing whilst still having the HSS rod in the hinges to make sure the solder doesn't flow out and obstruct the motion of the hinge. (because solder doesn't stick to HSS)
As soon as you're done, get rid of the excess flux and clean the surface of the brass. This will make your polishing job much much easier believe me.
To finish it off, cut along the previously marked curvature and make sure the pieces are still moving well and are fitting as planned. Drill two holes of 2mm each (yes I know I made an error there) corresponding to the holes on the ordinary coin.(refer to no.5)
Drill the holes carefully. The each need to be able to move freely and without obstruction. Moreover, they need to be exposed just enough to ensure that they function properly. If not, you can try and file the coins and make them a wee bit more flatter on the hinge side to allow the movement. At the same time, they do not need to be banking outwards as that'll increase its chances of incurring damages while being used.
Step 9: Assembly! (part 1)
Alright now this step really requires patience. You have two options here. You can either use suitable screws (fine threading of course) or use brass pins (1.8~2mm dia). I used brass pins because of the aesthetics and the durability which was slightly more because there are little to no chances of the pins coming off.
The technique is known as pinning and peening and you can look for tutorials on how to go about doing it online but let me remind you, it isn't something that comes to you instantly. It requires practice so I recommend you first practice on something else before assembling this using that very skill. Mine aren't all that perfect either but they'll hold up very well I'm sure.
IMPORTANT:Pin the hinges to the ordinary coin first then proceed with pinning the bimetallic else you'll have a hard time hammering the hinges and you'll end up damaging the bimetallic in the process. Observe the pictures.
You can even use Galvanized wire as the pins. Work your way out and while pinning the hinges make sure the hinges are not damaged in any way or aren't able to move because of the alignment. They need to be exposed and you need to make sure of this while drilling the holes in the hinges.
Step 10: Assembly! (part 2)
Test out the hinges one last time and their placement to see if everything is going according to plan. If you notice them wobble at this point, you might want to use very very small washers.
For this step, I used Galvanized wire as shown above only because I felt it was a little more rigid than brass. Rigidity is good for hinge rods as the last thing you want is a dysfunctional hinge.
It took all my experience and patience to carefully pin the hinges here. If you rush while pinning and peening here, you'll end up with a bent central hinge rod which will hinder free-motion. Use light strokes and never focus on a single point.
Step 11: Final Step- the LOCK.
Now cut a small piece of brass like the one in the picture. The piece is cut out of a 1.5mm sheet of brass. Remember that one hole that we left out? the 2mm hole? yep, this is why. Drill a 2mm hole and a 1mm hole carefully one next to the other with about a 2mm gap. The piece is 6mm long and 4mm wide.
Pin the piece on the outer face of one of the coins. The 1mm hole must be totally clear of any obstructions. Next, insert a brass-wire ring through the hole. The ring should be large enough to perform two things: Act as a link to the chain so as to make it wearable and act as a lock.
Next, grab the 2mm Galvanized wire and cut a 1.5cm long piece. Flatten one side and drill a 1mm hole like so.
Lock the piece half inserted into the 2mm hole and peen one end. The piece will be behaving like a pin over here.
From the chain, I salvaged the links and the lock and attached it to the piece.
Step 12: Cleaning Up.
Test if it opens up easily. Run a few other tests just to make sure everything is properly working. I added an additional coin there to make some space to keep stuff in but this is entirely optional. You might've noticed it in previous steps too. It is optional and will not affect the basic principle. You can use it as a necklace as I mentioned earlier. A rather heavy necklace yes. My sweetheart used a brass chain, opened up the links on either ends and closed them around the lock-ring for it to be able to hang. You may also use it as a key-chain yes.
Polish it to a mirror finish using first steel wire and then a buffing wheel with some solvents to give it the shine. Clean it well before presenting it. As I mentioned before, my girlfriend wanted the crude right-outta-the-production look so I only did the basic cleaning removing the flux and the dirt.
All you have to do now is gift-wrap it and give it to your sweetheart or mother or sister or wife and (hopefully) see them smile :)
Thank You for going through my Instructable and I hope you enjoyed. If you have any queries, feel free to ask. I'll reply as soon as I can in the comments below. Be sure to vote for me if you liked it!
Happy Building and Merry Christmas!