Testing Results

I’m very happy with the test results. Tweaking these recipes in my cone 8 kiln so that I can get as close to possible before taking up precious room in the big gas fired cone 10 reduction kiln. All of these recipes are based on the Leach 40 – 30 – 20 – 10 recipe method which so far seems very stable. Getting the specific gravity dialed in is important.

Testing rolls right along

So I’ve got all the chemicals I need to make a vast amount of glazes in my simple palate and color range. Testing to cone 8 in my electric kiln so I can tweak it as close as I can before putting it into the big gas fired kiln at cone 10.

  • Zircopax white over temmoku
  • White over Celadon
  • Temmoku over Celedon with a dip into the red iron oxide (FE2O3) as a differentiator test
  • Clear glaze by itself
  • Zircopax white by itself.

Im really excited about these simple glaze combinations. Along with red wild clay slip from the lake and black slip that goes to cone 10 I have a wide range of decorating possibilities to play with.

Previous Celadon glaze tests with incrementing FE2O3 from 2% to 12%


Testing the specific gravity of the glaze with hydrometer.


The only thing I may want to do different is to get more flux into the white glaze to have it run, almost like a Nuka style glaze over Temmoku.

John Britt’s Complete guide to High Fire Glazes has enough information to keep me busy for many years! Big thanks to Jay Benzel of Benzel Pottery for loaning it out to me.

Another thing I was working on was pulling technique and made a nice delicate serving spoon. Beautiful right?!

Not anymore! Haha! The spoon is just a spoon. ┬áThat’ll learn me to put stuff on the counter!

A long day getting ready

First thing to test is the kiln. If it is over firing or some other malfunction is going on its of no use to be even attempting to make a base glaze. Sarah from Olympic Kilns gave me a few cones to test with. I’ll place on each shelf so we can see if we are getting even heating from top to bottom. One thing I noticed in the last firing was that the click to turn on the elements stayed on longer than I heard it before. Almost a full 60 seconds. I don’t know if that has anything to do with it, but we’ll see.

I keep notes of glaze tests that I’ve done in the past but got a great tip from Jason and Megan at Stone Mountain Clay and Glaze – Keep a firing log and record the times that it takes to reach temperature and I suppose its good protocol to record the cooling times to room temperature as well. This will tell you if your elements are going bad or a thermocouple or something like that. Or maybe in my case if it runs very short and over-firing we’ll know by the time it is supposed to take to reach temperature. I’m trying to eliminate as many variables as possible as is standard in just about every type of troubleshooting.

Also on order and will be here shortly:

Amaco Hydrometer – for measuring and keeping a consistent glaze density

The range for dipping or pouring glazes is 0.9 to 1.00.

The range for spraying glazes is 1.5 to 1.7.

The range for brushing glazes is 2.2-2.5.

Kemper DTA Glaze Dipping Tongs – Because I’m tired of brushing on glaze and getting inconsistent applications.

Aftosa Wax Resist – For creating a more precise glaze line on the feet of my pots.

Stainless 8 Inch Caliper – I really really want to get into making lidded vessels.

Ozeri Pronto Digital Scale – Need precise measurements for each ingredient (duh!)


 

For those interested in the base glaze recipe that I intend to match to my white clay body

Recipe – Plainsman Cone 6 M370 Transparent Liner Base

Material Amount Units +/- *Stat
Nepheline Syenite 18.30 kg
Ferro Frit 3134 25.40 kg
EPK 19.60 kg
Wollastonite 6.90 kg
Silica 37.60 kg
Talc 2.30 kg
110.10

 

Witness Cones 5, 6 &7 to see where it ends up at and where in the kiln.
Respirator, because I like to breathe and want to continue to breath even after mixing dusty chemicals.

 

Christmas part 2! 5 lbs each of a bunch of chemicals.
Broken scale – new one on the way from Amazon!