Advice on what went wrong
Posted: Fri Jan 05, 2018 11:19 am
This is an experimental project I've been working on over the past few days. I'm somewhat satisfied given so many unknown variables, but clearly I need to tweak the process a bit to fix a few problem areas. I was using pieces of tempered red translucent "fire glass" for this project with an unknown COE. The mold was a 50/50 POP & silica flour. Rapid ramp to 1650F, hold for 30 minutes, then allowed to cool to room temperature over about 8 hours. Here are the photos:
https://drive.google.com/open?id=198GIi ... VWxrkPpRhy
1. I was slightly disappointed that my nice translucent glass shards turned opaque during firing. I've never experienced this before when using translucent glass.
2. Hole on the left side of the face. I'm assuming this is from an air bubble that developed when the glass was molten and it didn't have a chance to rise to the top of the mold before cooling. I'm not quite sure how to avoid that in the future.
3. Strange raised "ridge" that formed across the face during firing. It's about .25 mm high and clearly visible in one of the photos. At first I thought it was a crack, but closer examination showed it's definitely a ridge. There was no such feature in the mold, so I'm mystified how it formed.
I'm pleasantly surprised that not a single crack formed in the piece given the lack of using a firing schedule and the unknown COE of the glass.
https://drive.google.com/open?id=198GIi ... VWxrkPpRhy
1. I was slightly disappointed that my nice translucent glass shards turned opaque during firing. I've never experienced this before when using translucent glass.
2. Hole on the left side of the face. I'm assuming this is from an air bubble that developed when the glass was molten and it didn't have a chance to rise to the top of the mold before cooling. I'm not quite sure how to avoid that in the future.
3. Strange raised "ridge" that formed across the face during firing. It's about .25 mm high and clearly visible in one of the photos. At first I thought it was a crack, but closer examination showed it's definitely a ridge. There was no such feature in the mold, so I'm mystified how it formed.
I'm pleasantly surprised that not a single crack formed in the piece given the lack of using a firing schedule and the unknown COE of the glass.