Friday, July 6, 2012

Low Fire Friday - Base 3

Recently, I've been doing a lot of tests and line blends looking for a reliable, food-safe, base glaze that works well with Mason Stains. And I think I just may have found one that suits my needs!! 

Base 3 has a glossy surface, though not super crazy shiny. It's a bit semi-opaque with lower percentages of stains, and becomes opaque when higher percentages are added.


 


Base 3 - Cone 04

Frit 3134       75
EPK             15
Silica             10
__________________
                   100

Bentonite         2%


For color add...
The Mason Stains I've tested are:
  • #6236 - Chartreuse
  • #6026 - Lobster
  • #6379 - Robins Egg
  • #6025 - Coral Red
  • #6201 - Celadon
The test tiles pictured have line blends of these stains. A line blend is an easy way to get fairly quick results when testing colorant/stain in a glaze.

I mixed up a 100g batch of Base 3 for each of the above Mason Stains. (That's five separate 100g batches.) For each batch I started by adding 1% Mason Stain, or 1g. Then, to test how the glaze would look with 3% Mason Stain, I added 2g. Yes, only 2g because my 100g test batch already has 1g in it. For a 5% Mason Stain, I then only needed to add another 2g, and so on. It can get tricky so I always write all this down before I get started. Between each addition I brush a stripe on my test tile before moving on and adding more Stain.

I tested each Stain at 1%, 3%, 5%, 8%, 10%, 12%, 15%, 18%, and 20%. Some of the differences are too subtle to see in these images, but are more viable in person. 

This will give you a nice range of color saturation for each Stain. From these results you can decide what you like and do further testing if desired.

So, for example, if you like the color/look of the third stripe from the left on the Celadon Line Blend, then you would mix up the Base glaze with the addition of the 2% Bentonite and then 5% Mason Stain #6201 - Celadon.

I've labeled each image with the Mason Stain used and tried to test all colors on both red and white clay. (Though you can see the state of some of my test tiles is a bit rough and I'm missing red clay samples for the Lobster Stain and Chartreuse Stain.) 








Lots of testing, but if you're (crazy) like me, you love this part of the process! If you've got questions, just leave a comment or shoot me an email.

Well, happy glaze testing.
Meagan