Does it really mean stir for one hour? I won't even do that for carmels
(made with thick cream, sugar and corn syrup - to die for - literally).
Thank you again! Donna

"Steve Mills" wrote in message
...
I'm lucky over here; most of the clays I use will handle glazing while
dry.

I've just realized an answer that's been staring me in the face;

We found out while being Ceramic Suppliers that turning a glaze into a
brush-on almost without exception made it absolutely fine for raw
glazing regardless of the ingredients. The addition of CMC seems to work
the magic.
It was a chance discovery by a customer accidentally glazing some kids
earthenware models with commercial brush-on glazes without bisque firing
them.

The most important thing to remember though is that CMC is an organic
material, so MUST have some anti-bacterial material in it to stop it
going *off*!

I have a copy of the original information sheet we used to hand out, so
I have copied it and pasted it below.

Email me if you have any questions, remember to do what it says in my
address at the top of this post.

Note: Glowkil is an odourless commercial anti-bacterial preparation
which we used and sold. I can't supply any of this stuff now!

Steve
Bath
UK

BATH POTTERS' SUPPLIES Guidelines for making your own Brush-on Glazes

The process of making up your own brush-on glazes is fairly
straightforward. However
two important rules need to be observed:
1) make-up the glaze as for a standard dipping glaze.
2) when stirring in the CMC, use a medium or slow means of stirring;
because fast
stirring will make the organic polymer overheat and become stringy.

Basic recipe for earthenware glazes
To make 2 gal:
6 kilos glaze base powder e.g. B276.
9 litres of water.
270 grams CMC (organic polymer).
120 grams Glowkil (an anti-bacterial solution that increases shelf
life).
Colour.
Mix glaze, water, and colour together to the right proportions for
dipping glaze. Slowly add CMC. Stir well, for at least one hour. Allow
to stand for half an hour, add Glowkil and mix for a further ten
minutes, and then bottle down.
If you are going to leave the resulting glaze in the bucket, remember to
stir well before using it.

Stoneware glazes

2 gal prepared glaze.
100 g CMC per gallon.
45 g Glowkil per gallon.
Mixing instructions as for earthenware.

Raku brush-on glazes are very tricky to construct as the recipe varies
with each different coloured glaze. So it is down to trial and error
using the earthenware recipe as a starting point

Note
1) Glazes containing bone ash will need the amount of CMC in the
recipe reduced, the proportion will vary according to the amount of bone
ash used. Trial & error is the technique here as there are no hard and
fast rules.
2) Glazes containing Calcium Chloride glaze suspender are not
suitable for converting into brush-on glazes
3) These proportions are for UK based materials. Be prepared for
variations in materials local to you!



In article , Bob Masta
writes


Regarding the last question, you have to be very careful
when glazing bone-dry wa If it absorbs too much water,
the body can crack. Sometimes the cracking is not obvious
until after firing. I have given up using pour and dip methods
on bone-dry single-fire, but I suspect spraying would be OK
since you could keep it dry. (I am avoiding spraying since
I don't have a setup for that.)

Something else you might want to consider, at least for
experimentation if not for production, is using a base other
than water for pour and dip glazing of bone-dry ware.
The idea is that water rehydrates the body and causes
expansion cracking, but some other vehicle may not.
So far I have only tried oil (canola). I just mixed up the
regular glaze recipe but added oil instead of water.
This basically works, but it is really hard to use because the
glaze is left as a vrey loose powder on the surface of the
piece... reminds me of butterfly wing scales. So I ended
up with unavoidable finger smudges just from moving the
ware into the kiln, etc. But for a production operation you
might be able to use tongs or something.

I suspect any non-aqueous solvent would be a good candidate
to try. The problem is finding one that is cheap and safe.
For example, concentrated alcohol might work, but who can
afford that except for someone-off masterpiece? And
various low-weight solvents might work, but who wants
to have gasoline or xylene, etc, in the studio?

If anyone has any ideas for other solvents, I'm all ears!

Best regards,


Bob Masta
dqatechATdaqartaDOTcom

D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Home of DaqGen, the FREEWARE signal generator

--
Steve Mills
Bath
UK