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Chris Campbell

Troubles With Curves

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Chilly - I know exactly what you mean about going over your head! I've read all the posts, and watched the video clips - and I get it a bit BUT the penny hasn't really dropped yet. Is it definitely the Epsom salts for glaze that goes like concrete at the bottom? I've got a jar that I've saturated, but need to re read everything again before I try it! Have also got Dispex but I still feel that some of what I read seems to be saying the opposite of what I thought it was saying! NOT a Sunday night thing. Have just got back from an Anglian Potters' demo day - think I'll mull that over this evening and get on to clarifying the flocc and deflocc stuff tomorrow!

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Celia - for me I definately have "to do it" "to understand it".  VARK rings a bell, from a PTLLS course I did a few years back.  That was a whole learning curve in itself.  It taught me not to get involved, too much Elf and Safe Tea, Equal Tea and Lit/Num for a "pottery evening class wannabe tutor".

 

Watching the video of JB carving the glaze off the bottom of the pot reminds me of almost all the stoneware glazes I have ever seen or used, with the exception of Amaco's Potter's Choice.  I have three of them, and they sit in their pots all suspended, ready for a quick stir and brush on.  So, as soon as I find out where to buy Epsom Salts, I'm going to try it.  I need to do some glazing in the next couple of weeks for another stoneware firing.......  I'll let you know how I get on.

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Boots for the Epsom salts - sold as a laxative!

 

You've got the better of me with VARK, PTLLS, Elf, Safe Tea and Equal Tea??? You'll expand your list of acronyms no end if you get into education - it's riddled with them!

 

Fingers crossed with the glazing.

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Boots for the Epsom salts - sold as a laxative!

 

You've got the better of me with VARK, PTLLS, Elf, Safe Tea and Equal Tea??? You'll expand your list of acronyms no end if you get into education - it's riddled with them!

 

Fingers crossed with the glazing.

There are other deflocculants, Darvan just a trade name, in the UK you should be able to get sodium silicate and Sodium Carbonate which last forever.

Joh Britt has worked in his field for many years. Start by making a thick slip form dried clay, and do as he does.

Do what he does, it is very efficient and sufficient.

If you have time to wait till water to come to the top of your thin slip to drain it off, you are  a lucky person!!

Epsom Salts, Magnesium Sulphate is a Flocculant, sold in Supermarkets, or pharmacies. and it is a laxative, even used as a bath soak for aching limbs!!

Good luck! How is the British weather. From an ex pat who has been known to complain about the high 30sC experienced this summer!

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Chilly - I know exactly what you mean about going over your head! I've read all the posts, and watched the video clips - and I get it a bit BUT the penny hasn't really dropped yet. Is it definitely the Epsom salts for glaze that goes like concrete at the bottom? I've got a jar that I've saturated, but need to re read everything again before I try it! Have also got Dispex but I still feel that some of what I read seems to be saying the opposite of what I thought it was saying! NOT a Sunday night thing. Have just got back from an Anglian Potters' demo day - think I'll mull that over this evening and get on to clarifying the flocc and deflocc stuff tomorrow!

If you get doubtful, do what JohnB did and take a little out of your main bucket and test it. see what hapeens and go from there. Won't destroy anything.

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Lana Wilson's Magic Water formula for joining:

  • 1 gallon water
  • 3 tablespoons or 9.5 grams liquid sodium silicate
  • 1 1/2 teaspoons or 5 grams soda ash

I use it, I like it a lot.  I mix up a gallon and keep it in the shop always. I use a stiff toothbrush or cone shaped brush to apply it and work the joining area well. Since using it with HS students I had much fewer joins come apart and fewer seam cracks. So I decided it was a good thing.

 

 

Interesting.

 

Does it work well, on bone dry pieces, or those that are close to being so?  This is generally, when I run into the most issues, with student projects, despite my warnings to be very careful at this stage.

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Lana Wilson's Magic Water formula for joining:

  • 1 gallon water
  • 3 tablespoons or 9.5 grams liquid sodium silicate
  • 1 1/2 teaspoons or 5 grams soda ash

I use it, I like it a lot.  I mix up a gallon and keep it in the shop always. I use a stiff toothbrush or cone shaped brush to apply it and work the joining area well. Since using it with HS students I had much fewer joins come apart and fewer seam cracks. So I decided it was a good thing.

 

 

Interesting.

 

Does it work well, on bone dry pieces, or those that are close to being so?  This is generally, when I run into the most issues, with student projects, despite my warnings to be very careful at this stage.

 

 

Benzine if you tear up a bit of paper, tissue, toilet and blend it into the magic water  ie make it more like paper clay, i add a bit of theclay body as well, it will work better with drying out stuff: apply to both pieces.

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Lana Wilson's Magic Water formula for joining:

  • 1 gallon water
  • 3 tablespoons or 9.5 grams liquid sodium silicate
  • 1 1/2 teaspoons or 5 grams soda ash

I use it, I like it a lot.  I mix up a gallon and keep it in the shop always. I use a stiff toothbrush or cone shaped brush to apply it and work the joining area well. Since using it with HS students I had much fewer joins come apart and fewer seam cracks. So I decided it was a good thing.

 

 

Interesting.

 

Does it work well, on bone dry pieces, or those that are close to being so?  This is generally, when I run into the most issues, with student projects, despite my warnings to be very careful at this stage.

 

 

Benzine if you tear up a bit of paper, tissue, toilet and blend it into the magic water  ie make it more like paper clay, i add a bit of theclay body as well, it will work better with drying out stuff: apply to both pieces.

 

Ah yes, I've heard of that too.  Can that be smooth fairly well?  I believe I've seen Marcia post a recipe with paper pulp, clay and vinegar. 

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Magic water will not adhere bone dry pieces, but I have used the trick of the paper, magic water, and some slip. Mostly water and paper-slip for color. You will probably get some minor cracking in bisque but if they treat it real gentle should work out.  I found it did the best for me when I got them used to assembling leather hard slabs with the magic water working it to a slip with tooth brush. A lot of kids had problems getting slip too thick and not being able to work seam well-this helped.

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Magic water will not adhere bone dry pieces, but I have used the trick of the paper, magic water, and some slip. Mostly water and paper-slip for color. You will probably get some minor cracking in bisque but if they treat it real gentle should work out.  I found it did the best for me when I got them used to assembling leather hard slabs with the magic water working it to a slip with tooth brush. A lot of kids had problems getting slip too thick and not being able to work seam well-this helped.

I've been using something called "Ceramic Enhancer" for years.  It works pretty well, but I'm waiting for Norm to come in and tell me, that's it's something really cheap and common, that I shouldn't have been paying to have made for me....

The good thing about it, is that it really helps prevent the clay from cracking, while it dries, so you can essentially use it, in combination with slip, on bone dry clay.

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Score-No-More easily joins bone-dry clays.  It's pretty amazing.

 

I've broken-up bone-dry slabs and used Score-No-More to assemble the pieces into test tiles which immediately went into a bisque fire.

 

Pat Horesley's Score No More

100.0%  Dry Clay - the type you're using  == I just add the following ingredients to the wet clay I'm using

   2.0%   Feldspar Custer Potash

   2.0%   Bentonite

   2.0%   Gum Arabic / We use Xanthan Gum

   0.5%   Darvan

 

 

Lana Wilson's Magic Water formula for joining:

  • 1 gallon water
  • 3 tablespoons or 9.5 grams liquid sodium silicate
  • 1 1/2 teaspoons or 5 grams soda ash

I use it, I like it a lot.  I mix up a gallon and keep it in the shop always. I use a stiff toothbrush or cone shaped brush to apply it and work the joining area well. Since using it with HS students I had much fewer joins come apart and fewer seam cracks. So I decided it was a good thing.

 

 

Interesting.

 

Does it work well, on bone dry pieces, or those that are close to being so?  This is generally, when I run into the most issues, with student projects, despite my warnings to be very careful at this stage.

 

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Benizne - APT "Ceramic Enhancer" costing $5.95 per 3 oz at Axner is essentially Acrylic Floor Wax, a high-end floor wax which is a tougher version of Darvan, Elmers Glue, or common acrylic floor wax. http://www.axner.com/apt-ii-ceramic-enhancer.aspx

 

Ceramic Enhancer claims to be Acrylic Copolymer (which means a mix of acrylic copolymers) with Water and unreacted Monomers (decomposing acrylic copolymer).  They say it has an unlimited shelf-life, which is dubious, but to keep from freezing.  As with Darvan the percentage of Monomer will rise with time and rise very quickly and become almost completely monomer if frozen.  http://www.highwaterclays.com/index.cfm?fuseaction=feature.display&feature_ID=248

The APT "Porcelain/Stoneware Ceramic Enhancer" is also a mix of acrylic copolymers and water.  http://www.highwaterclays.com/index.cfm?fuseaction=feature.display&feature_ID=249

 

This acrylic floor wax is a mix of acrylic copolymers:  http://www.amazon.com/Harvard-Chemical-Thoroughbred-Premium-Copolymer/dp/B00C6OLYZI/

This is most likely what "Ceramic Enhancer" is. 

 

This mix of three acrylic copolymers is used for expansive car waxes, like the Zaino Z-2 Pro I use.  As the water evaporates, the polymers fully cross-link over the next 24 hours - or instantly if more "accellerator" 2-Ethylhexyl Acrylate is added.  Once cross-linked, the mix of four plastics are extremely resistant to detergents, UV, and and forms a hard plastic flexible plastic which is used for protecting all sorts of surfaces.

 

This less expensive floor wax consists of acrylic polymers - lower duty stuff like Elmer's Glue or Darvan:

http://www.amazon.com/General-Paint-Manufacturing-Non-Buff-1-Quart/dp/B003CENTMC/ref=sr_1_sc_10?ie=UTF8&qid=1392013130&sr=8-10-spell&keywords=Acrylic+Copolymer+Floor+Finish

 

All types of Darvans are Acrylic Polymers -- Darvan 811 is Sodium Polyacrylate $7.50 per pint (16 oz), while Darvan 7 is Sodium Polymethacrylate $6.35 per pint (16 oz). Darvan sold at Axner/Laguna is a very thick syrup.      http://www.axner.com/darvan-7-dispersal-liquid.aspx    http://www.axner.com/darvan811liquid.aspx

 

Acrylic Copolymers and polymers are an acrylic acid structure made of vinyl with carboxylic acid reacted.  Elmer's Glue is an Acrylic Polymer called Polyacrylic Acetate.  When Elmer's glue or Darvan are burned, you get the tell-tale smell of acrylic acid.  Burn some dry "Ceramic Enhancer" and you'll also smell the acrylic acid smell. 

 

A mix of Acrylic Copolymers with an activator is a tougher version.  This is a list of the Acrylic Copolymers   http://www.dow.com/acrylates/app/

Each product, such as the floor wax, is a different percentage of these four ingredients:

Butyl Acrylate;

Ethyl Acrylate;

Methyl Acrylate;

2-Ethylhexyl Acrylate (the trigger for cross-linking once the water is evaporated)

 

What's interesting is when this plastic burns out at 350 F, being Carbon, Hydrogen and Oxygen, it doesn't provide any ceramic flux, nor does the MSDS claim the presence of any flux salts. "Ceramic Enhancer" merely thickens the slip like Darvan and provides bonding and extreme greenware strength up to 350 F.

 

I'm sure you can use "Ceramic Enhancer" in place of Darvan and the Gum to make Score-No-More.

 

Magic water will not adhere bone dry pieces, but I have used the trick of the paper, magic water, and some slip. Mostly water and paper-slip for color. You will probably get some minor cracking in bisque but if they treat it real gentle should work out.  I found it did the best for me when I got them used to assembling leather hard slabs with the magic water working it to a slip with tooth brush. A lot of kids had problems getting slip too thick and not being able to work seam well-this helped.

I've been using something called "Ceramic Enhancer" for years.  It works pretty well, but I'm waiting for Norm to come in and tell me, that's it's something really cheap and common, that I shouldn't have been paying to have made for me....

The good thing about it, is that it really helps prevent the clay from cracking, while it dries, so you can essentially use it, in combination with slip, on bone dry clay.

 

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Benzine  --  Thanks SO much for the tip about using Acrylic Copolymers as a "Ceramic Enhancer"!

 

Adding a little Zaino Car Wax to clay is incredible.  I addition to starting with the three copolymer formula like ceramic enhancer, they add Siloxane - a hydrocarbon soluble silicone friction reducer which helps application and removal of the "wax" - actually a three monomer plastic.

 

The Half&Half Laguna clay quickly deflocculates and becomed extremely plastic - little force is needs to deform the clay-slip and it becomes very cohesive with the ability to bond heartily to dry clay other peices - drying absolutely hard.   The copoymers burn out at 350F leaving the intermeshed clay, from being deflocculated to sinter together on their own.

 

I'm going to look locally for the most inexpensive Actrylic Copolymer floor wax in a smaller container.  I don't think I'll be working with straight clay anymore.  But I can imagine situations where I'd also add bentonite and some frit for flux for repairs, but I'll wait and see.

 

As a protective covering, copolymer plastics are extremely resistant to detergents and bacterial action, but offer little protection from acid attack - so adding acid, say to change flocculation, would be contraindicated.

 

In terms of car wax, this means bird excrement which is extremely acidic needs to be removed quickly and additional copolymer wax applied.  The alternative is to apply alternate layers of copolymer wax and carnuba wax (which is acid resistant).

 

So far, it doesn't look like ceramic enhancer is less than double the price of comparable floor wax, so perhaps they dilute the wax with water before selling it as ceramic enhancer. 

 

 

I've been using something called "Ceramic Enhancer" for years.  It works pretty well, but I'm waiting for Norm to come in and tell me, that's it's something really cheap and common, that I shouldn't have been paying to have made for me....

The good thing about it, is that it really helps prevent the clay from cracking, while it dries, so you can essentially use it, in combination with slip, on bone dry clay.

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Norm, I'm glad I could provide you with a new product to test and explore.

 

The "Enhancer" really is good stuff, but with your recommendation of floor wax, I may have to raid the custodial closet, for more than just paper towels.

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Aaaah raiding the janitors closet, now those were the days. When I was in my 10th year or so one of the shop teachers retired-good friend. Left me all of his master keys!

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