george koller on sun 28 jul 02
> on 7/28/02 8:08 AM, William Hendry at whendry@CHARTER.NET wrote:
>
> > I am using a heavily fritted glaze sieved at 200 mesh for spraying and =
> > need to determine the best deflocculent to be using.
> > What are the pros and cons of using sodium silicate vs sodium carbonate?
>
> We use a very (read VERY) small amount of Darvan 811 to help with this as
> well as to obtain a better glaze poise.
>
> Jonathan
I added 20CC of KodaFlow Whetting agent to my last 500g dry mix of
glaze. Normally we add this to our colorants but I wanted to see what
effect putting it directly into the glaze would have. Well, the glaze just
about "poured" itself through our sieve and it sprayed on very well.
(I sprayed immediately after blending this concoction, and it was sure
easy to clean the mixing equipment.) I also added our normal amount of
sodium Silicate.
Would anybody care to speculate about this? I thought I could sense
somewhat improved dispersion but it has not possible for me to
measure increased dispersion.
Are whetting agents in a dried glaze likely to become "instantly" active
when sprayed upon by a colorant and aid dispersion? (My concern about
using the whetting agent directly into our metal sulfate colorants is that these
strong chemicals could break it down over time.)
And my last question is - what is glaze "Poise"??
Best,
George Koller
Sturgeon Bay, Wi - Door County
Where I'm looking forward to going to the next art fair and saying
things like "look at the great glaze poise on that gestural pot".
Ceramic Design Group on sun 18 aug 02
on 7/28/02 7:43 PM, george koller at gkoller@ITOL.COM wrote:
>> on 7/28/02 8:08 AM, William Hendry at whendry@CHARTER.NET wrote:
>>
>>> I am using a heavily fritted glaze sieved at 200 mesh for spraying and =
>>> need to determine the best deflocculent to be using.
>>> What are the pros and cons of using sodium silicate vs sodium carbonate?
>>
>> We use a very (read VERY) small amount of Darvan 811 to help with this as
>> well as to obtain a better glaze poise.
>>
>> Jonathan
>
)
>
> And my last question is - what is glaze "Poise"??
>
George:
Glaze poise is the "set" of the glaze on the ware.... how it breaks over
the surface with no runs.
Poise and viscosity are kind of related. I have been eyeballing the glaze
poise for our glazes. We use hot paraffin to wax the bases of some ware, and
I look at how the glaze quickly breaks over the wax leaving no runs on the
surface as an indication.
I have started to keep records of viscosity lately, but it really is only
relevant to use in your own shop as a reference point.
Best (sorry it took so long to get back to this answer
Jonathan
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