by AinsleyFrancis | Nov 25, 2008 | Firing Program, Kilncasting, Lost Wax, Sculpture
The original for this piece was wax, 9cm x 4.5cm x 5cm. The mold had a built in reservoir made out of clay. The mold was 60% Silica, 40% Plaster, and poured on Sunday November 23rd.
I measured 210g of cullet by water displacement, and filled the mold and reservoir with 191g of clear System 96 furnace glass and 34g fine ivory Powder (G102 FP).
The mold stayed intact through firing, on the following full-melt schedule:
1. 1:00 – 100
2. 14:00 @100
3. 21:00 -515
4. 24:00 – 600
5. 24:01 – 875
6. 31:00 @ 875
7. 31:01 – 515
8. 46:01 @ 515
9. 76:01 – 400
10. 100:00 – 50
The schedule was much longer than required for this size of piece because it was maximized for the largest piece in the kiln, which was Robyn’s spiked piece. The melt time was longer in order to make sure that the spikes filled, and the annealing time was long, because that piece was much larger than mine, and more fragile, so the program was very conservative.
More pictures of the process are here:
There were a couple of brown spots on the back of the bird after firing, which may mean that I didn’t steam the wax out of the mold well enough, or that the clear or ivory powder were contaminated.
by AinsleyFrancis | Oct 7, 2008 | Firing Program, Kilncasting, Lost Wax, Pâte de Verre
The mold for this bowl was an open-faced, lost wax plaster silica hand-built mold. I made silica molds of real star anise, and took wax impressions from those molds and attached them to a blank wax bowl. The wax was approximately 2.5″ X 5″. After the mold was built and steamed, there were quite a few really bad undercuts, where the plaster had filled in between the anise and the bowl, so I cleaned those up as best I could. The mold was approximately 2″ thick throughout. The mold was built on September 28th, and Steamed on October 3rd, 2008.
On October 5th, I packed the mold with System 96 powdered glass in the following colours:
1. Light Amber 5 clear : 2 colour
2. Gold Brown – 8 clear : 2 colour
3. Black Transparent – 5 clear : 2 colour
The mold was fired on October 6th, with the following pate-de-verre fusing schedule:
More details and pictures are available in the attached Picasa album.
I will re-make this bowl, as during the firing, the pate-de-verre slumped and pulled away from the edges of the mold, making the upper edge of the bowl rough and fragile. Also, a lot of plaster was fused into the glass, and is impossible to remove.
6 hours @ 100°C,
11 hours to 515°C,
13 hours to 720°C,
18 hours @ 720°C,
18.01 hours to 550°C,
25 hours to @ 550°C,
39 hours to 400°C,
46 hours to 50°