Tuesday, May 4, 2010

Silversmithing: Hammered Metal

It's not everyone who has a conversation with a friend including the sentence: "I found one. I dragged it to the park and hid it in the bushes. You can come and see if it's what you want. but you should probably come at night". Sounds like the beginning of a thriller - and in a way it is. It's pretty exciting to me anyway ...

My friend was talking about a tree stump. I had finally acquired a silversmithing hammer, but I had nothing to hit! I needed the stump as a solid base for hammering - sort of a wooden anvil.
Silversmith hammer and stump

I have set myself the task of making a bowl a week so that I get familiar with the hammer. This first one was small - just a three inch circle of copper, turning into a little bowl about 2 1./2" across.

bowl
It took about an hour and three annealings to get the shape. Metal hardens as you work it - so you have to anneal it (heat it up and quench it) to make it go soft again. For those of you who are interested in such things - when you hammer it you disrupt the even placement of molecules, which is what makes the metal get hard. When you heat it (to about 1500 for copper) the molecules are regulated again. If you keep baging it after it is too hard, it will break.

The next part was 'planishing' which harderns the bowl into its final shape and adds shine. Traditionally you use a stake and the flat side of the hammer - both are highly polished - and the metal between where the two strike becomes shiny and hard. You also create a pattern of hammer marks that is beautifully reflective with the light sparkling off the many planed surface. I was challenged here, becasue I didn't have a stake! (silversmithing tools are quite expensive - one small bowl stake being about $100) So I got creative, and used the hammer itself as a stake by putting it in my vice.

emergency silversmithing stake

I then polished the flat side of an old ball pien hammer that I had and used it for planishing

planishing

The results were lesss than perfect - but I was impatient to finish my first bowl! The planishing stake is in my budget for next month...

finished bowl

For me as an enamelist who has worked almost entirely two dimmensionally for years, it's very exciting to feel shapes forming under my hand. I hope that this will lead to a whole new world of design for me.

4 comments:

mary k mcintyre said...

OMG!!! Welcome to the club!!

I have an old trailer hitch that would make a *perfect* planishing stake -- you just need to dress the top into the shape you want, and polish it.

Yard sales, etc are great places to find old tools and chunks of metal crap that can be recycled into perfectly serviceable metal forming tools.

Would be happy to hook you up if you are interested... I have a grinder, sander & polisher at my place, too :)

imagocorvi said...

Thanks for the offer Mary - but I am not sure I could shoe-horn anything else into my already manic schedule. at this point paying the $100 would be worth it to save myself another job!
Actually that's why I like hammering - it's very peaceful!

mary k mcintyre said...

No worries... just wanted to encourage you if $ seems like a bar to more tools.

Good call on using your hammer as a stake, smithing tools are more flexible than people think.

Would be happy to show you a couple of tricks, if you are ever interested.

Cheers,
M

Laura Brito said...

We too have been doing some hammering, but not on this scale. I was just thinking how I would love to get a stake system and a good hammer for this. I am using cheapie hammers. Congratulations on the bowls, that is so neat! I will have to show this to the girls so they can see what it is all about!