Dinah Collopy on sat 26 oct 02
This recipe was given to me by the lab at Mason Color Works Inc. This
should be helpful to those other clayfolk who want to mix their own
underglazes. Personally I dislike small jars and prefer to mix up large
quantities that I can get my brushes into without feeling that I have to
look in the jar to see how much is left with every dip of the brush. It has
worked well for me in my initial testing. For those high fire folks: I
haven't tried the Liquid with oxides yet but it might work better than
glycerine and would not brush off as easily.
Mason Color Works has used this recipe for 50 years.
Glaze Type: Underglaze formula (measured in parts)
F-4 Soda Spar 20
Ball Clay 5
Frit (3124) 10
CMC Liquid 500cc
CMC Liquid(30 gms CMC to 1 qt. water) and let sit for 2 days to break down.
Antifreeze is Ethylene-Glycol and is toxic. For a non-Toxic substitution
use Proplyene-Glycol as a direct substitution. This mixture allows you to
use a brush and paint directly on greenware without your brush dragging.
Notes: Stain can be a mixture of Stain and Opacifier if a paler shade is
Further Note: I have substituted frit 3195 for 3124 in my own underglaze
mix and it works well. Mason Color Works has used this recipe for 50
It's a crisp -35 C. and the Northern Lights are spectacular this morning!
Paulette Carr on sun 27 oct 02
Making my own underglazes sounds like something that I would like to do. I
am a little confused about your (Harold's) underglaze formula. When I
measure in parts, are the parts by weight, volume or what? Are all stains
used at the 40 part level? Is this underglaze for greenware only?
I couldn't tell if this was a repost of Harold's original post, but if Harold
is not available to answer, are there others who can weigh in (no pun
intended) on this?
By the way, I use many of the Mason stains successfully at cone 9 oxidation
in a slip glaze (a glaze composed of 50% of my clay body). I would expect
something for underglazes.
Thanks for the clarifications. I am very eager to try this.
Marianne Lombardo on sun 27 oct 02
The underglaze formula would be by weight (grams).
Mix the CMC liquid first, and let it sit a day or two. You will have much
more than you need but can use it in glazes, etc.
Then take another container, label it "underglaze liquid" and by volume mix
all the liquid components.
Then, along with all the other ingredients, use weight to mix your batch of
underglaze. (You would use 75 grams of prepared underglaze liquid).
Underglazes may be used on greenware, or on bisque.
Omemee, Ontario, Canada
> Making my own underglazes sounds like something that I would like to do.
> am a little confused about your (Harold's) underglaze formula. When I
> measure in parts, are the parts by weight, volume or what? Are all stains
> used at the 40 part level? Is this underglaze for greenware only?