Sunday, October 24, 2010

Joy of Metal Clay: Fast Fire BronzClay - Part 2

Success!!!

Last week I began discussing the new Fast Fire BronzClay (check out last weeks post). I managed to successfully fire my first two batches of Fast Fire BronzClay test pieces. I am excited because the base metal clays can be finicky in their ability to sinter properly. I am hoping that there will be better consistency with this Bronze.?!?

Above, is a photograph of some of the fired bronze pieces next to unfired pieces. It gives a visual of the shrinkage. (I forgot to measure to difference between the pieces in order to determine actual shrinkage).
Directions for firing Fast Fire BronzClay can be found on the BronzClay website (Firing Fast Fire BronzClay).
I fired these bronze pieces in my Paragon FireFly top loading brick kiln. They were placed in a steel pan with activated carbon. I placed a one inch layer of carbon down, then my pieces ensuring there was approximately 1/2 inch space between each piece, then I laid down another 1/2 inch layer of carbon, then a few more pieces, finally I added a top 1/2 inch layer of carbon. The lid was place on top of the pan but it was off centered to allow air to escape. I ramped the kiln full speed to 1525 F then held the pieces at this temperature for 2 hours. Of note: the directions from the manufacturer do not give you an exact firing temperature. They recommend that you test fire pieces at 1525F and then adjust your temperature depending on the results from your kiln (blistering = temperature too high, unsintered clay = temperature not high enough).
Of all the pieces that I fired at 1525 F, I only had only one problem with one piece. Apparently if the firing temperature is too high you will get bubbling or blistering on your pieces. I found this with only one of the 20 plus pieces that I fired. Here is a picture below. The piece on the left has numerous bubbles whereas the piece on the right is completely smooth. It is odd that this only happened on one of the pieces....the only other reason this could happen is if your piece is not completely dry upon firing. I cannot explain this any further....it is what it is.
The final photo below is of the piece with a garnet coloured cz. It turned out fine but if you look closely you can see that there is bronze on the surface of the cz. Apparently I did not clean the surface of the cz...now the bronze is permanently attached to the cz. This is what happens if you don't clean your cz's before firing. To clean them I usually wait until the clay is dry and I will scratch off the clay with a toothpick, then I take cotton swab with rubbing alcohol on it to clean off the rest of the stone. (I guess I skipped this step in my excitement to get things fired!)

About durability of these bronze pieces, they withstood all the banging and bashing I tried!!! I have been unable to break any of the pieces that I have made.
One comment that I have heard it that if you overload your pan when firing or if you do not allow enough space between the pieces then you will run into problems in your firing.
I will keep you up to date about my tests. Next week I hope to post on a patina for Bronze!!!
Stay tuned.












4 comments:

Lisa Crone said...

I am in awe! This is GREAT!

Diana said...

I'm interested in trying silver clay and copper clay; can you recommend a reasonably priced kiln or firing method that doesn't take up too much room? I live in an apartment.

Diana

Fine Silver Girl said...

Diana...Firing methods are challenging to figure out the best option for you. In an ideal situation we all should be firing in well ventilated rooms away from our living quarters. That being said, I don't know many artist who have the luxury of doing this. There are many kilns on the market today. I have the Paragon FireFly which I love and was the most affordable at the time for me. If you are going to buy a kiln my advice is to get one with a digital controller as this will allow you to set the temperature and time and there is less of a need to baby sit the kiln. I do not know all the kilns on the market today. I will often refer my students to look at the WholeLottaWhimsy's website kiln comparison guide which gives good information. Or contact another similar supplier as vendors should a good idea about their products that they sell.

Our BeadFx buyer just informed me that they will be supplying the Ultralite Beehive kiln which I have tried some experiments with and I like it and have read good reviews about it. The only problem is you will not be able to get a high enough temperature to fire copper clay in it (I think its maximum temperature is 1550F.....

I will try and pull together some information on firing options and put together a post in the future.

One thing to consider is that when you get into working with metals like copper and bronze each brand has different firing recommendations. For example Art Clay Copper you do not need to use carbon in firing whereas Metal Adventures CopprClay does require carbon.

There is a system called the speedfire cone which is an open flame (reminds me of a camping stove) and I have a friend who fired both Art Clay Copper and Silver with it. One caveat though you don't have very much flexibility with this method and it is an open flame...not a great option for an appartment.

There are so many things to consider but hopefully this will help you start thinking about what you want or need.

Good luck. Heather

Dana said...

I am so glad I found this post. I have just started playing with the fast fire copper and white bronze powder. I absolutely love working with the new powder clays. So far I've done 3 firings and am not sure if I'm getting the best results. The directions I have call for a two step firing with the first one ramping full speed to 1000 degrees f for 30 minutes to 2 hours, cool to room temp. Fire again full speed to 1250 degrees f, hold for 2 hours. I had two of my larger round hoop shape earrings break (not happy) and the rest seems okay. However I can't figure out how to clean the fired pieces and bring them to a nice shine. Can you help?