Update to Firing Schedule of White Bronze

After firing White Bronze almost every day since it launched, I have arrived at a new schedule that works for both thin and thick pieces. It involved a little surprise, but I’ll save that for later.

Here is the new schedule:

Ramp at full speed to: 500°F/260°C; No hold.
Ramp at 400°F/222°C to:
      1160°F/626°C (top loader kiln);
      1250°F/676°C (front loader kiln)
Hold for 3:00 hours

If you don’t want to deal with 2 ramps, use the following, simplified but longer schedule:

Ramp at 400°F/222°C per hour to:
      1160°F/626°C (top loader kiln)
      1250°F/676°C (front loader kiln)
Hold for 3:00 hours

Total firing time is 4:00 to 4:30 hours.

You will find programming instructions on page 4 of the White Bronze instruction manual. All of the manuals – for Quick-fire clays, for White Bronze alone, and the Quick reference guide – have been updated as of 5/4/2010. Please download the new versions.

The manual for steel clay will be updated with the upcoming launch of Pearl Grey Steel.

Now to the surprise. I had a little piece of Quick-fire bronze that needed re-firing. Having nothing to lose, I decided to add it to a batch of white bronze. The repair worked! I then fired pieces of bronze with White Bronze, using the above schedule for White Bronze, and all the bronze pieces fully sintered, although the firing temperature was lower by 300 degrees than what is required for bronze. It seems that at least in this case, slow ramping and longer hold time compensated for the lower temperature.

Furthermore, I included in this batch a mixed piece of bronze and White Bronze. Here it is, as it came out of the kiln:

t-From the kiln

And here it is after sanding and buffing:
t-After sanding

Why is this good news? First, if you have just a few pieces of bronze and White Bronze, there is no need for separate firings.

Second, contrary to what I thought before, in order to combine bronze with White Bronze, it is not necessary to fire the bronze first; they can be fired together following the White Bronze schedule.

So, if you want to mix copper, bronze, and White Bronze in the same piece, you have two options:

1. Fire the copper first, then add bronze and White Bronze and fire again;
2. Fire the copper and bronze first, then add White Bronze and fire again.

I am currently testing combinations of copper and steel. Copper and steel, too, can be fired in the same batch with the same firing schedule. There is no need for separate firings.

Pearl Grey Steel and copper can be combined in the same piece, and the results are amazing!

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