I built a kiln modeled on Ian Gregory's ceramic flat pack fiber kiln using 2" thick 8# ceramic fiber rated to 2300F..
www.ian-gregory...
I built the kiln for Raku firing, but on it's maiden voyage, I decided to try a bisque firing. I was inspired to try bisque firing in this kiln based on a video I saw from Simon Leach doing a bisque firing in a somewhat similar kiln.
• SIMON LEACH - Raku kil...
I did not opt to use cone packs for the firing, but being a pottery newby and not having ANY experience other than Raku firings in my pottery class, I opted to use a cheapo digital pyrometer for my first attempt at bisque firing. Believe me, it was worth it's weight in gold!
I used a weed burner for my kiln burner, but to avoid propane tank freeze up, I bought a fitting off eBay that enabled me to run two 20 pound tanks into a common regulator. The eBay fitting came with an 11" water column regulator, but I replaced that with a 20 pound, adjustable high pressure regulator. With the twin tanks and regulator, I had steady pressure throughout the firing and no issues with tank freezing. (By the way, I estimate the entire firing consumed about 2/3rds of a single 20 pound tank's worth of propane)
I searched the internet high and low for any info on bisque firing, and came up with a planned firing schedule based on a number of resources. I was worried about being able to regulate the kiln at very low temps, so I opted to pre heat and dry my pottery overnight in a kitchen stove oven. All the pieces were bone dry, but regardless, I started heating them in the kitchen stove at 10:15 the night before at 170F and bumped the temp up 5 degrees every 15 minutes until it was at 220F.before going to bed leaving the oven door cracked open an inch or so. In the morning at around seven, i closed the door and bumped the temp 20 degrees F every 15 minutes until it was at 345F. (By the way, my worries about low temp regulation were unfounded)
Meanwhile, I set up my kiln and pre-heated it. By 9:00am, the kiln was at 360F. I shut off the kiln propane, transferred my pottery to the kiln, and commenced firing!
At 9:30am, with the kiln loaded and propane off, the temp inside was 170F. By 4pm (6 1/2 hours later) the kiln was 1925F. I kept detailed notes of my firing schedule and will be happy to share with anyone else interested in attempting to bisque fire in a fiber kiln!
I was extremely pleased with the way the kiln worked and my ability to control the firing. I rate this as a success. (At least before the kiln opening tomorrow!)
I will post a follow up video showing results after i unload the kiln tomorrow.
By the way, during the video, if you hear me say "cone 6" or "cone 5", etc., I really mean cone 06 or 05. (Sometimes when multitasking during filming solo, what you MEANT to say isn't what you actually say! Mea culpa.)
12 сен 2024
