Sad first firing - amaco PC glazes - help please!

[elaine clapper]

As others have mentioned it also looks like you need to check the elements on your kiln and use cones to check temp.  Your images look like the glaze is underfired. Your firing times do seem long.  If I go much longer than 8 or 10 hours on my Skutt kiln, I know I it is time to check the elements.   I have worked with PC glazes for years and love them.  I am sure the type of clay you makes a difference but this is what works  me.... I use laguna Bmix clay bisque fired to cone 04. That is a higher temp than your bisque firing and might help eliminate gases escaping clay during glaze firing.  I generally layer the glazes with dipping.  Glaze fire to cone 6 with a 5 minute temp hold at the end.  If you are interested look at my website, everything is done with Potter's Choice glazes. 

[oldlady]

one very inexpensive tool for slowing the cooling in a manual kiln is a simple kitchen timer.   2 are  better than one.   if you do not stay with the kiln, set one for more time you kind of think it will take, say 40 minutes, set the other for 10 minutes and carry the second with you to wherever you are going to be.  return to the kiln  right at the 10 minute mark and check.  reset less than 10 minutes and keep the second timer with you.     decide to stay at the kiln at some point.   when you finish, the first timer should show how many minutes actually  elapsed so you know what to expect next time. 

[Pres]

Hi folks, seems like you have covered most of the firing information for a setter kiln, and it is true that firing without a controller is different. Firing without either is much the same. When I taught at the HS, I found a couple of work arounds with the orton setter on the L&L. I did not know Min's trick with pushing the button and being careful with the drop bar, but worked around it with a loop over clothes hanger wire placed over the cone bar and drop bar to allow me to fire down. 

Color chart is really helpful, as a reminder of what you are seeing through the peep or otherwise. My kiln at home never had a setter, and I fired it up and down. It takes note taking, and awareness with experience to use the chart, but it helps. .  until you don't really need the chart. You know that I have my kiln in the garage/shop, not attached to the house. I have a slight gap in the top of the kiln that allows light to come out of the kiln. I can stand in my kitchen, see the white washed walls of the shop and the red, then the orange red, then the orange, then the orange white line about 1/2 " wide on the opposite wall of the kiln. I know that when it gets to orange, I should be watching closer.  I start going out about every 15-20 minutes then. Watching carefully the cones, and the heat color at top and mid, using switches to balance heat color.  I am watching for that yellow white that indicates ^6, and when that cone is at 90 degrees I turn back all switches to 50% allowing the firing to back down, this is usually only 2 hrs., then I am shutting everything down.  Will it work for you? Probably not, but that is not the point.  I have been firing this kiln regularly about once a month for over 36 years. Some years I fired it 3 times a month, and with 4 sections deep and 10 shelves high. I know the kiln, I kept exacting notes, learned while I worked. Now it is second thought, and I admit I don't keep many notes anymore. I know when a firing takes too long, and know when the elements were last changed, or when I cleaned it out last.  To really know how to fire a kiln like this takes going through much the same steps as I did, and learned to do from reading. . .reading . . . and effort.

Sad thing is now I will join the rest of you to use a programmable kiln. Life will be easier, right? Not really as I will be starting the old process once again, learning the kiln.  However, now it becomes more complicated as I will have to deal with the controller, wifi connections, and setting up ramp schedules! UHhhhhhhh!

 

best,

Pres

[oldlady]

"setting up ramp schedules!"     is scary enough to me that i found a clay and glaze combination that fit the kiln manufacturer's programs very well.   it took awhile, changed clay several times to get exactly what i wanted.  tested over 500 glaze recipes to find the color and finish i wanted.   we all work differently, use differing clay and glaze recipes and styles.   i am very thankful that i have a computerized kiln to take over the work of finishing what i started.

if you are a new owner of a computerized kiln, the manufacturer's normal programs might work very well for you, too.   just because you can program the series of steps does not mean that you have to.    pres uses his schedule for his style of work on the clay and glazes he has found gives the best results for him.   it did not happen overnight.   it will not be overnight for you, either.

for many years of learning by testing, i used a paragon 18x18 inch kiln with a kiln sitter, loved that babysitter on the side of the kiln.    such technology!!