Thursday, April 15, 2010

Experimenting with "White Bronze" clay

The last couple of years have seen an influx in new metal clays, including bronze, copper and steel made by different companies.  The latest in these is a new "white bronze" that Hadar Jacobson is making.  She supplies her metal clays in powder form and so you mix them yourself by adding just water.

I liked the look of her new white bronze clay so thought I'd give it a try.

As I often find with Hadar's clays, when I mix them according to her directions, they seem to slump when making thicker sculptural pieces and this is what happened with my first try with white bronze.  As it dries, it just doesn't hold it's form and flattens out.  So I decided to cut that piece into three and use them for some test firings to check what temperature is correct for my kiln.

Here's what one of the cut up pieces came out like after firing - finished only roughly - dark silvery grey color:


I then made up a new batch and added less water than Hadar suggests so that it wasn't quite collecting in the bowl.  Then I rolled this, adding the tiniest more bit of water,  and it came together and didn't slump as it dried.  It is on the verge of cracking but doesn't quite - so it is not the satiny feel that Hadar uses for her pieces and shows in her videos.  Anyhow - this drier form seems to keep sculptural pieces in their shape.

I made two of the drier batches and have just fired those.  The kiln settings seem fine - but both these pieces came out quite yellowy.  Here's one of my little birds -  not as yellow as traditional bronze but still a lot yellower than the test piece.  (I tried firing niobium wire embedded in him but it seemed wobbly which is what the little blob on his head is!):


So the final color of these last two pieces - each made with a different batch of drier clay - is quite different from the test piece and also from Hadar's work on her blog.  I can't imagine that just adding less water would take away the "white" coloring so I wonder what it was?  I'll see what Hadar has to say.

Here are three pieces for comparison.  The bird on the left is silver, the test piece in white bronze is in the middle and the yellowy white bronze bird is on the right.



Maybe it's just me and bronze! The prometheus bronze came out pink and now the white bronze comes out yellow????  Anyone else been trying this out?  what did you find?

4 comments:

Sue McNenly said...

So I'm easy...done now. I prefer your silver bird so I guess I don't need to run out and get white bronze. I keep changing my mind...yes,no,yes,no.

Laura Smith-Hos said...

Hi,
Thanks for sharing yoru experiments. I wish I could find time to share all of mine, but a 4 yer old son, means not much time left for show and tell if I want time in studio.

Two things though, I mentioned this on the Metal Clay Yahoo group, the pink from prometheus (which I don't like, too much like copper!) the pink can be removed/ reversed TWO ways that i know of...one fire it in carbon for as little as 30 minutes afte your first oen...ONLY MAKE SURE you have no black stuff loos left, since they will also trun mbak into Bronze in carbon and be loose flaky metal scales.

OR use Hydrogen Peroxide pickle. I believe normal Sparex pickle mixed half and half with HP is the recommended ratio. :-)

TWo: are you VERY sure that the blackish grey piece is fully sintered?? I had some of my first test pieces come out that color....and it turned out that REFIRING them at a slightly higher temp made then turn the normal silvery white color. I have what I would call a pretty good color match with some fine silver wire I mechanically embedded ij the white bronze, BUT it required a slightly higher than Hadar's minimum than recommended.

Anyway, just a thought, since i also was originally disapointed in the dark color, but they are ALL silvery white now after higher temp! I will try and get some bad pictures taken sometime soon to share. :-)

Regards from Borneo,
Laura Smith-Hos

Unknown said...

Hi Laura,
What temperature do you fire it at, and do you have a front load or top load kiln?
I'm also having trouble with one of my students pieces cracking, she tends to use less water than the rest of us, wonder if that's a problem?

Robin said...

I had nothing but problems with the White Bronze.

I couldn't get it fully sintered to save my life. I'm not new to Metal Clay. I've been doing it for a quite awhile. The pieces came out blackish grey too and when I sanded they were crumbly inside. I tried following Hadar's direction but this clay is not a "quick fire" at lower temperatures. I fired again and again to try and get them to sinter. Finally I went higher with the temp but it was too late by then and they were ruined.

I'm going to give this one more try. I really want to get a handle on this clay because I like the look of the White Bronze. Only this time I'm going to follow my instincts. I know my kiln and I need to go to a higher temperature right from the start. I going to fire it like the "Fast Fire Bronze" only I'm going to shorten the firing time and fire one piece at a time. If this doesn't work I'll do a 2 phase fire only I'll fire at a higher on the 2nd.