So, since I was stupid with the last molds, this is a "too many part" mold making technique. I invested my waxes in a two part mold, using vasaline as a resist. They came apart well, though some of them I made too thin ad they broke... that's ok. I separated them and steamed the wax out, then wired them together and hand built a mother mold to hold them together. Then I built a massive reservoir and attached two of the molds to it, and poured a second mother mold over that. Horrah! I used a lot of vasaline to create a gap, and shaved away parts of the space between the original two-part mold to deliberately create fins, in hopes that the glass would flow better.
Were fired on April 4th with the following schedule, which I stole from Jesse's sandy screwdriver:
1. 2:00 to 100C
2. 12:00 to 150C
3. 22:00 to 650C
4. 26:00 @ 650C
5. 26:01 to 870C
6. 36:00 @ 870C
7. 36:01 to 515C
8. 46:00 @ 515C
9. 66:00 to 400C
10. 78:00 to 20C
The molds were still wet when I checked them, so I added 8 hours to the drying cycle when I checked at 380C. I unloaded the kiln on April 10th, and let the molds sit for a few days.
None of the molds worked... In the picture above the are the three on the left and the one on the far right. They all worked better than the last time I fired scissors, though. I'm not really certain why they didn't work, since some of the ones from the next firing (the two really finny ones), which was exactly the same, did work. maybe the built-in fins were not so apparent in these molds. The straight half of the scissors did tend to work better anyways, so I'll put success rates down to easier flow in the ones that didn't have a bent handle.
Pictures of this firing are here:
Labels: Kilncasting
