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Am still at the very basics Have not added any color to anything If someone would be so kind as to explain in “ simple terms “ what the differences between Engobes , Stain , Mason stain , and Pigments are And then Underglaze And Overglaze ?

Thank you Nicky

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1 hour ago, Nicky S said:

Am still at the very basics Have not added any color to anything If someone would be so kind as to explain in “ simple terms “ what the differences between Engobes , Stain , Mason stain , and Pigments are And then Underglaze And Overglaze ?

Thank you Nicky

In the search bar at the top, type in those subjects.  There is a LOT of information on this forum concerning stains, engobes, Underglaze, etc.  Once you have read through that, you will have many more questions, that can help to clarify!

Roberta

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Add slip t'that list!

Amaco's site has a partial glossary (this is it startin' with S entry): https://www.amaco.com/terms?letter=S

   e.g. "Liquid clay, usually with colors added, with varying shrinkage rates, used for decoration. Since slips, engobes, and underglazes do not melt and flow like glaze, detailed decorations are possible."

...here's another http://walkerceramics.com.au/resources/glossary-of-ceramic-terms/

The distinctions between engobe, slip, underglaze may not explicit; for me, I want to know at what stage is the mostly clay colourant applied, does the colour stand firing (else changes how), how the colourant interacts with glazes, what's the target firing temp, does it fit my clays, etc. From there, I'll go with the whichever term.

For colour, I've only ventured as far as glazes, slips, and underglazes. I'm using Speedball underglazes (mostly on account o' they're supplied at the local JC, hence I bought five of my favorite colours for use at home).I blend up clay with some water, then screen out the sand and grog for slip*; I've black, red, white, and buff clays, so same colours in slips. For glazes, I chose seven recipes and am working on testing them out, as I didn't want to go with store-boughten glazes... 

At present (I'm a pottery neophyte), my understanding is engobe goes on damp/green clay, slip may be applied to green or bisque clay, depending on its formulation, underglaze goes on bisque ware (now I'll duck, lol).

Mason is a guy that markets stains; his stains can be used "...to color glazes, underglazes, slip, and clay. These ceramic stains are fritted raw materials. Frit is essentially one or more colorants encased in glass then powdered..."

For me, pigment is a more general term.

Overglaze, aah, perhaps includes china paints, lusters, and majolica?...oh, another glossary! https://digitalfire.com/4sight/glossary/glossary_overglaze.html

I'm not feeling very well today, have a bit of a temperature and a stuffy ol' head, :(; had fun looking at some glossaries though!

Mostly just wanted to post this pic, I'm so happy with this red slip under clear liner glaze!!!

*

 

small enough.JPG

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I always thought it was a "guy named Mason," - John Mason ('cause that's my era). But prior to him, masons are brick and stone layers. Mason stains are formulated to stain grout and are now used for all kinds of other clay stuff.

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1 hour ago, Hulk said:

Add slip t'that list!

Amaco's site has a partial glossary (this is it startin' with S entry): https://www.amaco.com/terms?letter=S

   e.g. "Liquid clay, usually with colors added, with varying shrinkage rates, used for decoration. Since slips, engobes, and underglazes do not melt and flow like glaze, detailed decorations are possible."

...here's another http://walkerceramics.com.au/resources/glossary-of-ceramic-terms/

The distinctions between engobe, slip, underglaze may not explicit; for me, I want to know at what stage is the mostly clay colourant applied, does the colour stand firing (else changes how), how the colourant interacts with glazes, what's the target firing temp, does it fit my clays, etc. From there, I'll go with the whichever term.

For colour, I've only ventured as far as glazes, slips, and underglazes. I'm using Speedball underglazes (mostly on account o' they're supplied at the local JC, hence I bought five of my favorite colours for use at home).I blend up clay with some water, then screen out the sand and grog for slip*; I've black, red, white, and buff clays, so same colours in slips. For glazes, I chose seven recipes and am working on testing them out, as I didn't want to go with store-boughten glazes... 

At present (I'm a pottery neophyte), my understanding is engobe goes on damp/green clay, slip may be applied to green or bisque clay, depending on its formulation, underglaze goes on bisque ware (now I'll duck, lol).

Mason is a guy that markets stains; his stains can be used "...to color glazes, underglazes, slip, and clay. These ceramic stains are fritted raw materials. Frit is essentially one or more colorants encased in glass then powdered..."

For me, pigment is a more general term.

Overglaze, aah, perhaps includes china paints, lusters, and majolica?...oh, another glossary! https://digitalfire.com/4sight/glossary/glossary_overglaze.html

I'm not feeling very well today, have a bit of a temperature and a stuffy ol' head, :(; had fun looking at some glossaries though!

Mostly just wanted to post this pic, I'm so happy with this red slip under clear liner glaze!!!

*

 

small enough.JPG

You got slip and engobe backwards, slip is used on greenware and engobes are for bisqued.  Engobes are usually formulated with less clay to reduce shrinkage, kind of a mix between a clay and a glaze.  Slips are usually mostly clay and shrink with the clay body.  I love slips! I just say no to white glaze now and slip my dark clay bodies.

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33 minutes ago, Rae Reich said:

I always thought it was a "guy named Mason," - John Mason ('cause that's my era). But prior to him, masons are brick and stone layers. Mason stains are formulated to stain grout and are now used for all kinds of other clay stuff.

It's was actually a couple from Stoke-on-Trent England, James Mason and Mary Skerratt Mason who founded Mason Stains in the 1840's. She was a colour chemist. The company originally supplied stains to the whiteware industry. They moved to East Liverpool Ohio in 1902 and since then the company has expanded into the ceramic gas log industry, pool and spa pigments, coatings and plastics colourants plus they developed a cobalt nucleating agent that is used in medical devices and turbine blades for jet engines. Lot of history behind this company.

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Enjoyed readin' some of the Mason story (http://www.masoncolor.com/mason-color-history); current president Carol Mason. Note the page spells color, hmm, I still slip* on that, having first attended school in Barrow, learned colour. ...marketed by the Mason family, or Mason company better than a guy named Mason, my bad. I'd seen a pic of John Mason somewhere in earlier...

 

"You got slip and engobe backwards, slip is used on greenware and engobes are for bisque."

   Yep, probably did! The materials marked engobe at local JC ceramics lab is for application to greenware only (although there are a few containers by the glaze table that are for bisque). DigitalFire indicates "In terracota and stoneware processes, engobes are most often applied to leather hard ware." As for slip, I'm seeing recipes for application on greenware and bisque.

  DigitalFire has a paragraph in the Slip entry "The difference between a slip and an engobe" - both are still liquid-y mostly clay t'me.

* :)

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Just now, liambesaw said:

Yeah, I have seen the terms used interchangeably before.  It's been explained to me that engobe is more like part glaze part slip. 

Plastic clay bodies, engobes, and slips fall under the Atterberg Limits. (PL) plastic limit is the amount of water a clay body will hold while still maintaining plastic properties. Engobes and slips are (LL) liquid limits: the amount of liquid a clay body will hold above the plastic limit; but still maintain its collidial properties. EX. 100 grams of dry clay body will hold 20-24 grams of water and still be within its plastic limits. Potters call it soft, medium, or firm clay. Engobes hold 32-35 grams, and have higher colloidials,properties. (?Paste like). Slips have 40-42% water typically: achieving a pourable state but still maintains its colloidal properties. 

PSD ( particle size distribution.) is different between plastic clay, engobes, and slips. Once you add past a clay bodies maximum colloidal limit: it loses its ability to pack. Better known as chunky soup when you pull it out of a mold. :)

spars are often added to engobes pending application: to which some compare to "glaze" additions. More common to add oxides to engobes as well.

T.  

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I'm trying to find a good fitting slip/engobe for my high iron body, and this last test yielded some good results.  Using John Britt's cone 6 white slip, which is more of an engobe I suppose (due to the high flux).  

WHITE SLIP CONE 6 

Nepheline Syenite 15.00 
Kentucky Ball Clay 25.00 
EPK Kaolin 25.00 
Ferro 3124 10.00 
Silica 25.00 

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I use slip made from commercial wet clay and apply to wet, leather hard, and bone dry ware for decorative effects.  Have never had a problem of adhesion, cracking, or anything else.   I fire at cone 10 reduction.  Have use slip from cone 04 clay bodies -- white and red -- that becomes true glaze at cone 10; cone 5+ slips produce various colors and textures, especially when the slip has coarse particles added to the slip.   If find that these mediums (scrap commercial clay bodies) are adequate, easy to deal with, and do not require any real special treatment.   I try a mixture, and if I like the result I go for it. I use this approach for various clay bodies:  Coleman, Nara, Armadillo porcelain,  Tuff Buff stoneware, all of Armadillo cone 10 clay bodies - including Raku clay,  B mix (cone 5 and 10 with and without grog), Soldat 60,  Calico red cone 5 clay, B-3 Brown cone 5 clay, recycle clay,  my own pond clay,  and a few other unknowns.  I started this approach years ago, and it works fine at both cone 5 and now at cone 10 firings.    The idea developed into a personal technique from my boredom with plain surfaces and an inquisitive nature for trying to see what happens if … .  

This approach follows the quote alleged to have come from a chicken hawk (and passed to me by my grandfather):  "some days 'u get chicken, 'n some days it's feathers"  .  Regardless of the source, the idea is to keep trying combinations of available resources (and materials) to make pots that are your pots.   The approach with the slips has expanded to use "dry slips" (dry powders applied over a sticky wet surface) to produce decorative effects that are attractive and interesting to me and to others.  

LT

Edited by Magnolia Mud Research

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i hope we have not driven Nicky into the loony bin.    you have not told us anything about how you came to pottery or what education you have in the field.    if you are learning on the fly, read on.

nicky, you are only at the very edge of the beginning of learning about pottery making and finishing.   get yourself some basic books,  (they are portable and not subject to interruption by not being recharged).   some very old textbooks written before your parents met.   you will find explanations of all kinds of things you do not want to make but the process is the same for what you do want so learn how to do the basics.   look at previous posts  about what books you might want.

and just FYI, slip is the simplest thing to color and use.   use it on wet clay, not bisqued clay.   yes, it can be done but why set yourself up to learn something so complicated when it is so easy to use slip made from your own clay and water plus color.    experiment with lots of things,  i know your first pots seem to be as valuable to you as the mona lisa but they are really only practice for making good work later.   

 

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Thank you all ALL for your help and kindness @oldlady I have only have limited access to internet info Which I find difficult as I have a learning disability So always looking for simplified explanations I’m self taught  on the wheel which I initially started as a form of therapy And even tho very challenging at times I’m sticking to it and good for peace of mind 

But feel now is the right time to try and start adding some color ( I’ve managed to bisque fire a couple of times and glazed using a transparent glaze ) And have just started throwing a bit with porcelain which even more challenging but is so beautiful on its own

Maybe my best option and probably easier would be to use only commercial colors (?) 

Does that mean I need different materials for stoneware and porcelain or just the glaze ?

And last but not least as I have my kiln in my apartment  was wondering at what temp are the fumes are the most dangerous Even with open window the fumes are rather strong sometimes 

Thank you Nicky

Edited by Nicky S
Wanted to add title

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Nicky it is extremely dangerous to fire a kiln in your living space. I would definitely find another solution for your firing. Clay and glaze maturity are both achieved by many chemical reactions/changes. All these reactions release little bits and pieces into the air that will end up in your living space. 

 I love your enthusiasm for this wonderful field of study I hope you keep with it it’s very rewarding!

Edited by Mullins Pottery
Needed to add a bit

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10 hours ago, Nicky S said:

Thank you all ALL for your help and kindness @oldlady I have only have limited access to internet info Which I find difficult as I have a learning disability So always looking for simplified explanations I’m self taught  on the wheel which I initially started as a form of therapy And even tho very challenging at times I’m sticking to it and good for peace of mind 

But feel now is the right time to try and start adding some color ( I’ve managed to bisque fire a couple of times and glazed using a transparent glaze ) And have just started throwing a bit with porcelain which even more challenging but is so beautiful on its own

Maybe my best option and probably easier would be to use only commercial colors (?) 

Does that mean I need different materials for stoneware and porcelain or just the glaze ?

And last but not least as I have my kiln in my apartment  was wondering at what temp are the fumes are the most dangerous Even with open window the fumes are rather strong sometimes 

Thank you Nicky

@Mullins Pottery Thank you for your advise

I’m not to keen on the idea either but my only option I’m afraid. I also have emphysema so am as cautious as can be.  I leave balcony doors open and hope wind blowing in right direction (s) But was wondering if certain temperatures where mayb more toxic than others I fire  980 -1200 

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Sorry---you can't vent an indoor kiln by opening a door, using a fan, and hoping the wind is blowing in the right direction. This simple overview is from L&L kilns--you need to get more info  so you can vent the kiln to the outside properly, and to assure it's not coming back in.  Ask your questions--with more specifics (size of kiln, your firing range etc.) --in the Equipment Use and Repair forum on this site.  If searching via the Internet isn't great for you, ask on that forum if there are a few simple books you could get that will cover most of what you'd need to know for how you are working. Here is the link for this     https://hotkilns.com/ventilation-essential      There is more than what I pasted here, it continues with ventilation Tips. 

  1. Kilns generate harmful fumes when firing ceramics.
  2. Fumes include carbon monoxide, sulfur oxides, hydrogen fluoride and metal vapors (all of which can be very toxic).
  3. Install kiln in well-ventilated area.
  4. Never operate in an enclosed space such as a closet unless you have good ventilation.
  5. Aside from issues of ventilating the fumes from the firing, the heat build up in an enclosed room could present a significant fire hazard. See the INSTALLATION cautions.
  6. Severe corrosion can be caused by kiln fumes, salt air or other environmental conditions.
  7. Good venting can minimize these problems.
  8. Ventilation must be to the outside.
  9. Be careful not to locate the outlet of the vent near an open window (so that it could get sucked back into the building).

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