search  current discussion  categories  techniques - slips 

how to deflocculate a pint of slip

updated tue 31 jan 12

 

gina mars on mon 30 jan 12


Hi All, I have been experimenting with printing on clay and read an =3D
article that suggested deflocculating
my slip before applying it to clay. I'm not sure how much sodium =3D
silicate is needed in a pint of purchased
amaco slip or even a pint of slip I have made myself. It would be a =3D
shame to waste it if I did it wrong. Does anyone
have an idea of how to do this? My sodium silicate is in liquid form.
Thank you, Gina Mars
www.marspottery.net
Fabulous weather in Huntington NY this week.=3D

ronroy@CA.INTER.NET on mon 30 jan 12


Hi Gina,

Find out first if it is already deflocced.

I defloccc throwing slip to decorate under Tenmoku and Celadon glazes.

You would need to dry out some of that slip and crush it to a powder -
and I use Darvan #7 but sodium silicate will work as well. The Darvan
is said to leave more margin for error. Soda ash will work as well -
most slip casters use both soda ash and sodium silicate together - I
forget why - or something like Darvan.

First take off as much water as possible - if the slip is still thin
add powdered slip to get it thick - I would just do a cup and keep
track of what you do so you know how much of defloccer and dry clay to
add next time.

Now add a drop at a time (either sodium silicate or Darvan - and stir
let it sit for a few minutes and stir again - as soon as the slip goes
thin - add more dry clay - continue till the slip no longer goes thin
as you add more deflocker.

All kinda messy but the deflocced slip will not crack.


Quoting gina mars :

> Hi All, I have been experimenting with printing on clay and read an
> article that suggested deflocculating
> my slip before applying it to clay. I'm not sure how much sodium
> silicate is needed in a pint of purchased
> amaco slip or even a pint of slip I have made myself. It would be a
> shame to waste it if I did it wrong. Does anyone
> have an idea of how to do this? My sodium silicate is in liquid form.
> Thank you, Gina Mars
> www.marspottery.net
> Fabulous weather in Huntington NY this week.