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calgon for terra sig

updated sat 3 jul 04

 

Donna Nicholas on thu 1 jul 04


I mixed up a Joan Tweedy recipe for terra sig that called for Calgon. After two days the stuff in the glass jar looks more like tofu than terra sig; it didn't separate at all. I'd ordinarily assume that I'd made a mistake in weighing and measuring, but I checked my figures several times. Is the Calgon sold on grocery store shelves these days different from the Calgon we used some years ago? If Calgon is no longer okay for terra sig, can anyone suggest a conversion ratio from Calgon to sodium silicate? Any other flocculants being used for terra sig these days?
Thanks, Donna

Donna Nicholas
nicholas12@earthlink.net

Lee Love on fri 2 jul 04


Donna Nicholas wrote:

>I mixed up a Joan Tweedy recipe for terra sig that called for Calgon. After two days the stuff in the glass jar looks more like tofu than terra sig; it didn't separate at all. I'd ordinarily assume that I'd made a mistake in weighing and measuring, but I checked my figures several times. Is the Calgon sold on grocery store shelves these days different from the Calgon we used some years ago? If Calgon is no longer okay for terra sig, can anyone suggest a conversion ratio from Calgon to sodium silicate? Any other flocculants being used for terra sig these days?
>
>
Old calgon is Sodium Hexa Meta Phosphate NaPO3.. Louis Katz said new
calgon is mostly soda ash (can you look on your box and tell us what it
says?)

Digital Fire says to use : 0.25% (1/4 of 1%) soda ash AND .25% sodium
silicate (the two together seem to work better than either by itself)

Wonder if you could just try .25% sodium silicate with your "Calgon".
Check and see what your Calgon is made of.

I found a box of old Calgon at a friend's house. You could
tell by the graphics on the package. I asked my friend if I could buy
it. They gave it to me. They sometimes managed estate sales and got
this box from an estate they were helping sell.

--
in Mashiko, Japan http://mashiko.org
http://journals.fotki.com/togeika/Mashiko/ Commentary On Pottery

Frank Gaydos on fri 2 jul 04


You need to get some Sodium Hexametaphosphate. That was the old Calgon.
I get mine from Dharma Trading in Ca. You also can get it at any fabric
tie-dyers suppliers.

http://www.dharmatrading.com/html/eng/2204-AA.shtml

Frank Gaydos

----- Original Message ----

> I mixed up a Joan Tweedy recipe for terra sig that called for Calgon.
After two days the stuff in the glass jar looks more like tofu than terra
sig; it didn't separate at all. I'd ordinarily assume that I'd made a
mistake in weighing and measuring, but I checked my figures several times.
Is the Calgon sold on grocery store shelves these days different from the
Calgon we used some years ago? If Calgon is no longer okay for terra sig,
can anyone suggest a conversion ratio from Calgon to sodium silicate? Any
other flocculants being used for terra sig these days?
> Thanks, Donna
>
> Donna Nicholas
> nicholas12@earthlink.net
>
>
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>

Lee Love on sat 3 jul 04


Frank Gaydos wrote:

>You need to get some Sodium Hexametaphosphate. That was the old Calgon.
>I get mine from Dharma Trading in Ca. You also can get it at any fabric
>tie-dyers suppliers.
>
>http://www.dharmatrading.com/html/eng/2204-AA.shtml
>
Thank you for sharing this Frank. I have used "old calgon" water on
the outside of gas fired bean pots, to make the bare clay toasty (it is
what I replaced dipping the same pots in the top water of shino
glaze.) Learned this use from Shirley Johnson.. Glade to see a new
source.

--
Lee in Mashiko, Japan http://mashiko.org
http://journals.fotki.com/togeika/Mashiko/ Commentary On Pottery