Jump to content


Photo

Redart


  • Please log in to reply
40 replies to this topic

#1 ayjay

ayjay

    Advanced Member

  • Members
  • PipPipPip
  • 333 posts
  • LocationHampshire, UK.

Posted 02 August 2013 - 03:44 PM

I'm starting to get away from bought glazes and mixing my own instead, mostly from previously published recipes but I like to give them a tweak here and there,. (firing to ^6 Ox)

 

I often see Redart listed as a glaze ingredient and am wondering if any red earthenware clay will provide a good substitute or is there something special about Redart which makes it particularly suitable as a glaze ingredient?

 

I have access to some Fremington clay and obviously any other clay available at suppliers here.



#2 OffCenter

OffCenter

    Advanced Member

  • Members
  • PipPipPip
  • 1,372 posts

Posted 02 August 2013 - 03:52 PM

Earthenware clays aren't interchangeable but some may be close enough to sub for each other, especially if the earthenware clay is a low percentage of the glaze. You may get a glaze that works but it will not be the same glaze. You can compare the two clays you mentioned here:

http://digitalfire.c...edart_1191.html

and here:

http://digitalfire.c...html?logout=yes

 

Jim


E pur si muove.

"But it does move," said Galileo under his breath.

#3 oldlady

oldlady

    single firing an electric kiln to cone 6

  • Members
  • PipPipPip
  • 1,015 posts
  • Locationharpers ferry west va and pinellas park fl

Posted 02 August 2013 - 04:42 PM

it would be good to know where "here" is.   in USA?


"putting you down does not raise me up."

#4 oldlady

oldlady

    single firing an electric kiln to cone 6

  • Members
  • PipPipPip
  • 1,015 posts
  • Locationharpers ferry west va and pinellas park fl

Posted 02 August 2013 - 04:57 PM

ok, jim, 

 

the recipe i have for a red clay that fires at cone 6 is made up of only 2 ingredients.  half redart and half XX saggar.   it is very hard to break.  i have had pieces fall 6 feet to concrete and not break or chip.  it rings nicely, too.  why does it work????


"putting you down does not raise me up."

#5 OffCenter

OffCenter

    Advanced Member

  • Members
  • PipPipPip
  • 1,372 posts

Posted 02 August 2013 - 07:18 PM

ok, jim, 

 

the recipe i have for a red clay that fires at cone 6 is made up of only 2 ingredients.  half redart and half XX saggar.   it is very hard to break.  i have had pieces fall 6 feet to concrete and not break or chip.  it rings nicely, too.  why does it work????

 

The weathering and sedimentary process that resulted in Redart deposits also created a unique inverted chain crystal in that clay's phyllosilicate minerals that just happens to fit perfectly into the montmorillonite-smectite polly strands of colloid crystals in the more sedimentary XX Saggar producing partial reverse liquefaction.

 

Jim


E pur si muove.

"But it does move," said Galileo under his breath.

#6 oldlady

oldlady

    single firing an electric kiln to cone 6

  • Members
  • PipPipPip
  • 1,015 posts
  • Locationharpers ferry west va and pinellas park fl

Posted 02 August 2013 - 08:15 PM

love your answer.   thank you.  hey, axe, you listening??


"putting you down does not raise me up."

#7 Biglou13

Biglou13

    Advanced beginner pottery, Advanced in other art

  • Members
  • PipPipPip
  • 1,019 posts
  • LocationNorth Florida

Posted 02 August 2013 - 11:31 PM

love your answer.   thank you.  hey, axe, you listening??


Axe doesn't like 2 part clays........

ok, jim, 
 
the recipe i have for a red clay that fires at cone 6 is made up of only 2 ingredients.  half redart and half XX saggar.   it is very hard to break.  i have had pieces fall 6 feet to concrete and not break or chip.  it rings nicely, too.  why does it work????

 
The weathering and sedimentary process that resulted in Redart deposits also created a unique inverted chain crystal in that clay's phyllosilicate minerals that just happens to fit perfectly into the montmorillonite-smectite polly strands of colloid crystals in the more sedimentary XX Saggar producing partial reverse liquefaction.
 
Jim

Jim are you being funny or is that real clayspeak
Caution big brother is watching.
The beige is blinding!!!!!!
The middle of the road is boring

The true sign of intelligence is not knowledge but imagination.
-Albert Einstein

#8 trina

trina

    Advanced Member

  • Members
  • PipPipPip
  • 437 posts

Posted 03 August 2013 - 06:13 AM

Ha, Jim I see you are finally reading that book I lent you....T



#9 oldlady

oldlady

    single firing an electric kiln to cone 6

  • Members
  • PipPipPip
  • 1,015 posts
  • Locationharpers ferry west va and pinellas park fl

Posted 03 August 2013 - 09:05 AM

but he did spell poly wrong.


"putting you down does not raise me up."

#10 Biglou13

Biglou13

    Advanced beginner pottery, Advanced in other art

  • Members
  • PipPipPip
  • 1,019 posts
  • LocationNorth Florida

Posted 03 August 2013 - 09:58 AM

Old lady Any pictures of that clay?
Caution big brother is watching.
The beige is blinding!!!!!!
The middle of the road is boring

The true sign of intelligence is not knowledge but imagination.
-Albert Einstein

#11 oldlady

oldlady

    single firing an electric kiln to cone 6

  • Members
  • PipPipPip
  • 1,015 posts
  • Locationharpers ferry west va and pinellas park fl

Posted 03 August 2013 - 10:23 AM

i just looked at all my own pots and found that there are 3 of them made in that clay.  the only thing that shows the color is the bottom which had been waxed before glazing.  i can take pictures but not post them here since i just don't seem to get them right.  the color is the color of redart.  plain red brown.  make up 5 pounds and try it. it is very smooth but you could add grog since it is inert, (i think) and won't affect much more than tooth and color.

 

i stopped using it because my hands were constantly stained by it.  it  is a really good clay.

 

i used the cement mixer at Foxcross Pottery and just tossed in a bag of each, some water and turned it on.  Del Martin had set up the cement mixer years ago and allowed me to use it.  i took home 6 or 8 five gallon buckets of fresh clay each time.


"putting you down does not raise me up."

#12 nigich22

nigich22

    Member

  • Members
  • PipPip
  • 16 posts
  • LocationLouisville KY

Posted 03 August 2013 - 10:55 AM

Out of curiosity could you make that two part clay with Goldart as opposed to Redart? 



#13 ayjay

ayjay

    Advanced Member

  • Members
  • PipPipPip
  • 333 posts
  • LocationHampshire, UK.

Posted 03 August 2013 - 11:13 AM

OK, thanks everyone,  I'll test something!  :D

 

@ Old Lady: "here" is still in the UK.



#14 Wyndham

Wyndham

    Advanced Member

  • Members
  • PipPipPip
  • 430 posts
  • LocationSeagrove NC

Posted 03 August 2013 - 12:36 PM

You could try gold art or any other clay but it might not vitrify at cone 6 or it might over fire at cone 6 and become a glaze puddle.

 

Make up a sample test tile and fire it your next cone 6 firing and see what it looks like, then weight it and write this in a note pad or glaze book. Soak the test tile over night in water, take  and towel dry it and weigh it again. Note the difference in weight if any, this is the of  water absorption. If it's 1% or so that's vitrified the higher the water content the more pourous the clay.

 

Testing is a lot of fun in both clay making and glazing

 

Wyndham



#15 Marcia Selsor

Marcia Selsor

    Professor Emerita, Montana State University-Billings

  • Members
  • PipPipPip
  • 4,007 posts
  • Locationwhere Texas, Matamoros, Rio Grande and Gulf of Mexico come together.

Posted 03 August 2013 - 08:01 PM

Out of curiosity could you make that two part clay with Goldart as opposed to Redart?

no, because Goldart is a stoneware clay. Redart is a low fire clay.
Marcia

#16 OffCenter

OffCenter

    Advanced Member

  • Members
  • PipPipPip
  • 1,372 posts

Posted 04 August 2013 - 04:39 AM

 

love your answer.   thank you.  hey, axe, you listening??


Axe doesn't like 2 part clays........

 

ok, jim, 
 
the recipe i have for a red clay that fires at cone 6 is made up of only 2 ingredients.  half redart and half XX saggar.   it is very hard to break.  i have had pieces fall 6 feet to concrete and not break or chip.  it rings nicely, too.  why does it work????

 
The weathering and sedimentary process that resulted in Redart deposits also created a unique inverted chain crystal in that clay's phyllosilicate minerals that just happens to fit perfectly into the montmorillonite-smectite polly strands of colloid crystals in the more sedimentary XX Saggar producing partial reverse liquefaction.
 
Jim

 

Jim are you being funny or is that real clayspeak

 

 

Just another half-assed attempt at humor.

 

Jim


E pur si muove.

"But it does move," said Galileo under his breath.

#17 Marcia Selsor

Marcia Selsor

    Professor Emerita, Montana State University-Billings

  • Members
  • PipPipPip
  • 4,007 posts
  • Locationwhere Texas, Matamoros, Rio Grande and Gulf of Mexico come together.

Posted 04 August 2013 - 09:12 AM

Jim,
Dang! I was taking notes!
Marcia

#18 Wyndham

Wyndham

    Advanced Member

  • Members
  • PipPipPip
  • 430 posts
  • LocationSeagrove NC

Posted 05 August 2013 - 09:56 AM

EPK is a high fire clay as is ball clay. Goldart can be used, the effects may not be the same as expected and may turn out uugly as a garbage pail kid but it will give a wealth of information whether good or bad on learning about glazing.

Wyndham



#19 Biglou13

Biglou13

    Advanced beginner pottery, Advanced in other art

  • Members
  • PipPipPip
  • 1,019 posts
  • LocationNorth Florida

Posted 05 August 2013 - 06:44 PM

 

 

Just another half-assed attempt at humor.

 

Jim

 

i figured.    but i bit anyway.......


Caution big brother is watching.
The beige is blinding!!!!!!
The middle of the road is boring

The true sign of intelligence is not knowledge but imagination.
-Albert Einstein

#20 Biglou13

Biglou13

    Advanced beginner pottery, Advanced in other art

  • Members
  • PipPipPip
  • 1,019 posts
  • LocationNorth Florida

Posted 05 August 2013 - 06:48 PM

 

no, because Goldart is a stoneware clay. Redart is a low fire clay.
Marcia

 

are you saying you cant use a stone ware and low fire clay together in a clay body?

or is that the case for a 2 part clay body only?

is there literature rating dry material clay   temps  i know epk high  lizella earthenware     what about om4 and a host of other "usual suspects"


Caution big brother is watching.
The beige is blinding!!!!!!
The middle of the road is boring

The true sign of intelligence is not knowledge but imagination.
-Albert Einstein




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users