Following on from my post about anticlastic forms the other week, I thought I’d have a go at it’s opposite – the synclastic curve. A bowl is a good example of a synclastic form; if it was hammered from a flat sheet, the X and Y axis would curve towards each other as the bowl was raised. As I don’t have that much metal to play with, I’m making some earrings (pictured right). Luckily enough, my dad found several pieces of hallmarked fine silver in a draw – we’re not sure when we bought them, but it was a nice surprise, and it coincided with a quiet afternoon. I’m hoping that the results are good enough to use for my AA2A application. Working in fine silver provides a different experience to sterling – the metal is much softer, so it deforms with little effort. The upside is that it takes ages to workharden, and the downside is that it takes ages to workharden. After finishing the earrings, I think I prefer doing this kind of work in sterling – unlike the wire I made by hammering, which would have been a lot more work in sterling. It didn’t effect the final polish, so I’m not concerned, just interested.
The strips I used were originally intended for making a series of adjustable rings of varying sizes, but I noticed that two of the blanks were almost identical; it didn’t take much effort to smooth the corners and start turning them into earrings. The sheet was half-hard when we bought it, and I thought I should anneal it – something I regret in hindsight, as the metal could have done with a little rigidity. One thing that surprised me (but isn’t clear in the photos) was the finish that the torch left on the strips after annealing – the side heated by the torch took on an almost frosted appearance, which was very even and attractive, but not what I wanted. Dad suggested that it might be the expansion of the surface – if anyone knows any better, post a comment and let me know what it is.
In theory, a synclastic form is easy to make, and certainly the basic curves were very simple to put in. Using the leather-covered saddle stake from the anticlastic blog post, the strips were curved along the short axis, and then partially curved along the long axis. I then set up two stakes (actually different types of tools used as stakes because they were spherical). The domed grip on a mandrel was used for the wider end of the strip, and an inverted doming punch was used for the small end. I experimented with a few different tools before that, but the spheres worked best. The process was simple, and the bulk of the time was spent getting the appearance and symmetry just right. Uneven hammering would cause the two ends to move out of alignment, and this was solved by tapping the corresponding edge, so that when the small end veered left, the left edge needed stretching to take it back. Eventually, I was able to get them close to perfect. Then it was just a matter of soldering on some sterling earring posts and polishing the surface.
If these earrings were intended to be reproductions of ancient jewellery, then some other method of hanging them from the ear would be more appropriate. Different ways of attaching earrings to the ear isn’t something I’ve put much thought into – presumably something like a shepherds crook fitting would be more accurate, but I’ll have to research a post on that.
The curvature wasn’t as obvious as I would have liked – a deeper curve on the short axis would have been better. The earring posts needed to be adjusted when they were first tried on; the centre of gravity was way off, which was a good reminder that it’s difficult to design earrings if you don’t have pierced ears. I balanced the earring posts on a stick, until they hung well. The other design flaw was their weight – Danielle, who is modelling the earrings in the photo, found that they pulled on the ear lobe too much. Thinner metal might be a better choice in future.
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