Lost Wax Casting

Learning new stuff is one of my favourite things to do. I have been taking a course in silversmithing at Sheffield College to try a few of the things I can easily do (Yet!) in my home studio, such as casting.

Lost wax casting simplified is basically to carve a design in wax. Make an investment mould around the wax - a bit like plaster of paris. Then stick the mould in the kiln to burn away the was - hence the lost wax. That leaves you with a mould to pour your molten metal into.

Turns out you can actually cheat - you can use any item that burns away in the kiln instead of wax, so what I did is use some of my growing collection of dried pods and fir cones.

They have to be attached to a tree of wax called a sprue - this is the channel that the metal will flow into. Here's my first attempt.

Once the pods and wax was burned away in the kiln I was ready for the centrifugal casting machine!

Once the lid is closed the little arm inside with the balancing rod will spin around really fast forcing the metal into every corner of the mould.

 The silver was added to the white crucible and heated up till it was a round shiny ball. Time to slam the lid.

Once the silver has cooled a little the mould is grabbed with tongs and plunged into a bucket where all the investment starts to dissolve and you can fish around for your lump of silver in there.

This is what it looked like fresh out of the bucket. There is still gooey investment stuck to it and the silver is black from firescale and oxidation. I removed the goo and plunged it in the acid bath to clean the scale off.

It took a few goes, but eventually it came out looking like this:

It then has to be tumble polished to reveal the shiny silver:

Now I just have to figure out what to do with all my lovely little pods. I think the poppy seeds are destined to be tiny necklaces - they don't match in size for earrings. The conifer cones on the other hand are perfect for earrings. Tiny little dangles.

Back in the Studio

Phew. I’ve had a nice break. My sister is back to health, the convention is well over and things have settled down slightly except of course my work project which is now going full steam ahead. We’re trying really hard to finish it for an autumn release. It’s looking great and I am really pleased with it so far.

This weekend I had time to play with some silver and try out a few things that have been playing on my mind. It’s great to get back in the swing and see new things come to life. I have signed up for a course in metal clay, mainly to be forced to try out some new things and to see how other jewellers view my work. This can sometimes be scary, but they have been very supportive so far.

The earrings above are now in the shops. I’m happy with the design and toying with the idea of making more in a similar configuration; Silver sculpted stud adorned with a drop stone. I like the way it feels more secure because it is a stud, but still dangles as if it was on a French wire.

hollow core bead. New technique for me

Birthday Sunday

Don't you just love when you get unexpected birthday presents? Well. Any presents :o)

I just found out that I have won You Sew Should's giveaway:
   You Sew Should...: Giveaway Winners!:

Yay. I won!
I just love the cuteness of Gemma's design.
:o)

I have been spoilt today by my wonderful partner and family and have also had a chance to do a little Sunday Project.

It's made with three little pieces of sterling wire. I balled up 5 of the ends with my torch and on the last I soldered on a little orchid flower that I have moulded out of metal clay and fired till it became solid fine silver.

The two pieces were actually meant to become stacking rings in their own right. Simple rounds with a single bud or ball, but I messed up with the torch and burnt through the wire. Turns out it was a happy accident, as I love the result better than the simple rings. It was very fiddly to solder the three pieces together and I had to proceed very carefully so as not to ruin this ring with my love of fire :oD
I love the organic look. I think I might do more variations of this one. Maybe a leaf instead of the orchid, or a gem or...

Clear Out - Make room for the new

I'm having a bit of a clear out in my drawers.
Any jewellers out theere in need of some charms or Pandora style beads?

Following up on Bronze Clay

This is an addition to my previous post on bronze and copper clay.
So I've read up a bit about the Creative Bronze, and frankly it sounds like a general problem that it comes out looking more like copper.
One girl, Sabine Alienor, had very good results firing the clay in carbon in her kiln, which indicates that it might be an oxidation problem.
Since I don't have a kiln (yet) I decided to try removing the top layer of one of my bronze pieces to see if the core looked any different. So I took a heavy grind wheel to it. After heavy polishing and the leaf being a lot lighter, it does indeed look more like bronze, but it still has more of a pink tinge than I would like. Plus grinding half the piece off isn't really a good solution.

I think I might have to cave in and get a kiln, because I do love the look of bronze. Anyone got one going cheap?
:o)

Hook Sizes and Oxidising

Normal size ear hooks

I know, sounds boring right? But I've discovered that when I design tiny dangle earrings, I always imagine them hanging right under the earlobe, and then I make the hook compare and they’re miles lower than what I expected and wanted. Bigger hoops can be gorgeous of course, but I want to be able to choose.

I decided to try and take them right back, See how small I could make ‘fish hooks’ and still have them hold the earring securely.

Compared to the new small ones

The bronze coloured one is as small as I could possibly get to fit on my own ear. I was concerned they might be easier to unhook by mistake, but actually, since they fit so snugly they feel a lot more secure than large swinging hoops.

I don’t know if my lobes are average size – it’s just not the thing I have been noticing before (but now I will ;oD ) so I decided to make my next batch of hooks, just slightly bigger than the smallest that worked for me.

Here they are, ready for the oxidising process along with some of my new wire designs.

Bright copper before oxidising

I don’t use Liver of Sulfur but an alternative called Platinol. It works superfast and is much less smelly.

After dipping in Platinol

After a bit of steel wool cleaning, I let the pieces tumble for an hour. My partner has made me a tumbling machine out of wood and old printer parts He is so handy that way :o)

After polish