Wednesday, June 1, 2016

Summertime Madness

It's been several months since I posted, but I had to go through the drudgery of Spring semester and finals. Now that that's done, I'm free to go about my work I've been neglecting.

My biggest project right now is a knife I've had in the works for probably a year. Currently I'm wrestling with the ferrule and guard you can see here. I bombed an attempt of a guard and handle previously and then another one with the ferrule. I'm trying to see what I can do with the current project, but I've set it aside until I can get some of the subsequent projects finished.


The lines in the blade are the remainders of rasp grooves. If I were to grind them out, the blade would be a bit thin.
I had no saw blades for my jeweler's saw so I used a carbide bit and a drill on my Dremel to get started.
...and finished with files.
The guard was fitted and set.
I squared a copper pipe.
Cut it, and joined as you saw at the top.

The next project was a cool idea I saw on the internet.
And a few more I'm working on.


On top of that, I've been doing a lot of jewelry work.
A sterling ring, alloyed by me, forged by me.
Soldered (the bead is excess. It was cut and filed off later)

The ring was filed and set up for the next stage. Pictured with the ring above is a sheet of sterling silver I beat out from a lump. More annealing and cold forging was done after this picture. 
Next, flower patterns were cut out of the sheet with heavy scissors. The pattern was taken from one like this. 
After this, the petals were bent, formed, and soldered together.

The next phase will be to solder it in place and finish shaping, sanding, and polishing. I'm debating putting in a stone in the center, but it will be very challenging if I do.
 This is a cast I just finished.

A few issues with it, but I might be able to salvage it.

The next big project is a stone set into my ring I wear on my right hand. I talked about that in a previous post. I wear it everyday and am quite happy with it. However, I had heard about a type of setting called a gypsy setting.
This is essentially how it works. So, I decided, I needed to do this to my silver ring, but first, I did it on come copper sheet.




And that is done. I'm very happy with it. 

Lastly, I'm working on some gold refining. I have a large amount of old gold filled and plated jewelry. First, some terminology; Gold plated jewelry has a microns thick layer of gold that is added to base metals like brass, copper, or bronze through an electro-chemical process called plating. The process is used in jewelry, electronics, and steel (although in this case it is zinc and the process is called galvanization). Gold filled is a term to describe a mechanical process where gold is bonded with heat and pressure to a base metal. Gold filled results in a thicker, more durable coating of gold. This is used typically in watch cases and jewelry. These are marked typically with things like "1/10 12KT," "1/10 14KT," or "1/12 18KT." These describe the amount of gold alloy by weight, and the type of gold alloy by karat (a 24-ratio, 18 being 18/24 or 75% gold). 


To determine if an object is gold or a copper alloy, I discovered a solution of 2/3 3% hydrogen peroxide and 1/3 5% vinegar will serve as an indicator. Leave the piece in the solution overnight. If the solution is blue in the morning, you have a copper alloy. I discovered also that this solution will also eat at copper alloys and indeed, most metals while remaining largely non-toxic and relatively safe. The mixture is called peracetic acid. This is a useful solution that can be used as an anti-microbial agent on vegetable and hard surfaces if diluted to about 140-400 ppm. This is actually used in the kitchen I work in. However, my more concentrated solution eats metal in a matter of hours. 

As gold filled and plated jewelry is used and worn, it wears down the gold layer slowly. Hence the holes that appear and become tarnished on some old jewelry. This can be exploited to erode the base metal. If the gold is intact, simply cut it up to expose the inner layer.
The solution is strained and anything in the filter is collected.

Here's what happens to a watch case after several washes in the solution. 
The leftovers are a highly ionized solution. The copper ions in here really want to come out of solution so the peracetate and acetate ions will join to anything more reactive than copper. For this reason, do NOT pour this down a drain. It's not acidic anymore but it is highly corrosive. 
Aluminum is added to the solution so the copper (the dark stuff on the side) drops out of solution and since aluminum is the second most abundant material in the earth's crust, it will largely not react with anything down the drain. Now it is safe to dispose of. Soon the gold will be the only remainder material and it will be melted down to a single bead. 

That's all for now. I'll keep this updated the rest of the summer.

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