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Troubles With Curves

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#41 clay lover

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Posted 08 February 2014 - 08:07 AM

so is Magic Water a defloculant?



#42 Pres

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Posted 08 February 2014 - 10:32 AM

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.

 


Simply retired teacher, not dead, living the dream. on and on and. . . . on. . . .                                                                                 http://picworkspottery.blogspot.com/


#43 Chris Campbell

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Posted 08 February 2014 - 12:20 PM

Thanks Bcisket for the John Britt video and thanks Babs for hanging in here with me! ...
I understand now ... I learn best by seeing.

Chris Campbell
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TRY ...   FAIL ...  LEARN ...  REPEAT


#44 Norm Stuart

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Posted 08 February 2014 - 01:11 PM

Score-No-More shelf-life is primarily determined by the gum you use.

 

If you use a gum with a biocide which protects the gum, it will also protect the Darvan from biological attack.

 

There are more than a couple of threads going on here, and I have a question that relates to both.  I like the idea of mixing Pat Horsley's "Score No More" to slips...it sounds like a great solution to resolve Chris' slip-falling-off issue (there's joke there I'm sure, but I'm not going there).  But, since the Pat Horsley formula includes Darvan and Darvan, from what I have learned here, has a short(er) shelf life, does the Score No More have the same shelf life as the Darvan or is the shelf life shortened, extended, or not-affected by the Darvan component?

 

I'm still pretty old school when it comes to joinery. I do my best to make sure pieces are very similar in moisture content and use slip from the same clay on the scored surfaces to be joined...and then I compress the bejabbers out of it as it gets leather hard.  That bejabbering process probably knock the flock or de-flock out of my join issues ^_^

 

My son still swears by 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

 



#45 Norm Stuart

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Posted 08 February 2014 - 01:15 PM

Magic Water is both a deflocculant and a flux.  So it's the Darvan and Feldspar components of Score-No-More.

 

Score-No-More also has bentonite to fix stacking problems between two types of clay, and gum to provide non-clay adhesion between layers of clay which aren't bonded for any reason.

 

so is Magic Water a defloculant?



#46 Babs

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Posted 08 February 2014 - 05:50 PM

Thanks Bcisket for the John Britt video and thanks Babs for hanging in here with me! ...
I understand now ... I learn best by seeing.

No worries mate! clarifies it to explain it, and yes, J britt did it in a nutshell, well a bucket or 2.



#47 Norm Stuart

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Posted 08 February 2014 - 08:24 PM

The thing to remember using a deflocculant of any type is you need to give the slip enough time to settle out so you can pour off the excess water.  If you don't, the deflocculant is not actually reducing the water percentage of your slip.

 

Thanks Bcisket for the John Britt video and thanks Babs for hanging in here with me! ...
I understand now ... I learn best by seeing.



#48 Babs

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Posted 09 February 2014 - 01:40 AM

 

The thing to remember using a deflocculant of any type is you need to give the slip enough time to settle out so you can pour off the excess water.  If you don't, the deflocculant is not actually reducing the water percentage of your slip.

 

Thanks Bcisket for the John Britt video and thanks Babs for hanging in here with me! ...
I understand now ... I learn best by seeing.

 

That is why J Britt got his initial slip bleedin' thick to start off!



#49 Chilly

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Posted 09 February 2014 - 07:32 AM

Let's see what John Britt would say . . .



 

I've now watched these two videos several times, and I'm starting to understand.  Too much more info than that and I'll get all confused again.

 

What I need to do now is to purchase Darvan (I'm sure there is an alternative that is more readliy available in the UK - Sodium Dispex?) to thicken up my slip so I can have another go at slip trailing, and epsom salts to fix my glazes that pan at the bottom of the bucket.  Put the learning into practice and then I'll truly understand.  Reading and seeing only work so far, for me to really learn, I have to do it. 

 

Thanks for all the contributions, but some of the above has gone straight over the top of my head.  K.I.S.S.


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#50 Norm Stuart

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Posted 09 February 2014 - 12:27 PM

The generic name is Sodium Polyacrylate CAS number 9003-04-7 for Darvan 811, and Sodium Polymethacrylate CAS number 54193-36-1 for Darvan 7.

 

The CAS (Chemical Abstract Service) numbers are an international reference and can be used to call for any local brand name.  Other brand names are Dispex and Dolapix.

 

Bear in mind that to reduce the water content of slip or glaze, merely adding a deflocculant like Darvan like John Britt does is not sufficient.  You also need to let the clay particles settle, say over night, in order to pour off the excess water.  John Britt is constrained by the run time of the video, but he should have explained this.

 

 

Let's see what John Britt would say . . .



 

I've now watched these two videos several times, and I'm starting to understand.  Too much more info than that and I'll get all confused again.

 

What I need to do now is to purchase Darvan (I'm sure there is an alternative that is more readliy available in the UK - Sodium Dispex?) to thicken up my slip so I can have another go at slip trailing, and epsom salts to fix my glazes that pan at the bottom of the bucket.  Put the learning into practice and then I'll truly understand.  Reading and seeing only work so far, for me to really learn, I have to do it. 

 

Thanks for all the contributions, but some of the above has gone straight over the top of my head.  K.I.S.S.

 



#51 Celia UK

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Posted 09 February 2014 - 01:19 PM

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!

#52 Chilly

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Posted 09 February 2014 - 02:04 PM

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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#53 Celia UK

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Posted 09 February 2014 - 02:52 PM

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.

#54 Babs

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Posted 09 February 2014 - 04:58 PM

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!



#55 Babs

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Posted 09 February 2014 - 05:01 PM

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.



#56 Benzine

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Posted 09 February 2014 - 10:10 PM

 

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.


"Anything worth believing, is worth questioning"

#57 Babs

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Posted 09 February 2014 - 10:17 PM

 

 

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.



#58 Benzine

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Posted 09 February 2014 - 11:07 PM

 

 

 

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. 


"Anything worth believing, is worth questioning"

#59 Pres

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Posted 09 February 2014 - 11:19 PM

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.


Simply retired teacher, not dead, living the dream. on and on and. . . . on. . . .                                                                                 http://picworkspottery.blogspot.com/


#60 Benzine

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Posted 09 February 2014 - 11:25 PM

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.


"Anything worth believing, is worth questioning"




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