? Secret Ingredient In Underglaze?

[oldlady]

I have found two recipes for underglazes.  I have mixed one and blended colors all afternoon only to find that the underglaze I made powders off my greenware.  what is the secret ingredient?  the recipe calls for stain, frit 3134 and a few drops of gum solution.

[bciskepottery]

From Vince Pitelka: http://iweb.tntech.edu/wpitelka/syllabi-handouts/handouts/mason%20base.htm

 

My recipes for the Bringle slips also use a spar, clay, and silica plus oxides.

 

My notes show Lana Wilson suggests using 100 grams of dry clay body plus mason stain.

[Min]

I've tried a few underglaze bases, none of them have worked as well as Spectrum underglazes. Spectrum sells their underglaze base to which you add stain in approx a 2:1 ratio. (500 series base)

http://www.axner.com/spectrum1050underglazebase1pint.aspx

[oldlady]

thank you both. I have talked to mason stain's tech.  the recipe given from vince pitelks calls for gallons of ingredients.  I have the recipe for bringle underglaze, I also have one from Kathy triplett"s book. 

 

lana Wilson is making slip.  I have dozens of colored slips, I want to make underglaze.  I want to paint several colors and not have them come off if touched before firing.

 

I appreciate your suggestion, min, but I want to make it without depending on a large amount of a purchased base. 

 

does anyone know what prevents the powdering off?  or have Kathy triplett's contact info? 

[Min]

Have you come across this article about home made underglazes? 

http://ceramicartsdaily.org/ceramic-supplies/underglaze-ceramic-supplies-2/how-to-make-homemade-underglazes/

 

I'm with you on being as self sufficient as possible as to making glazes and slips but with underglazes  I agree with the summation made by Holly Goring that "the manufacturers do just a bit better, faster, and cheaper".

[Diane Puckett]

I have been told that Karo syrup added to glaze stabilizes it pre-firing. I have not tried it, but maybe it would help with your underglaze.

[Mark C.]

I'm not a commercial underglaze guy but is not the magic ingredient a secret???as its a secret for the commercial guys?

There are some paint additives that make things stick (many paint ingredients are glaze ingredients).

I got some from a paint store that makes paint for making salt kiln sprays.

Mark

[Min]

I'm not a commercial underglaze guy but is not the magic ingredient a secret???as its a secret for the commercial guys?

There are some paint additives that make things stick (many paint ingredients are glaze ingredients).

I got some from a paint store that makes paint for making salt kiln sprays.

Mark

 

Could be a secret ingredient but I think it's more likely that short of ball milling for hours we can't replicate the process to produce a colloid.

[Chris Campbell]

Of course there are 'secret ingredients' ... they hire scientists who qualified to design and test their products.

They spend years improving them so they are simple to use over a wide range of clay bodies at all stages and all firing temps.

They fire to the colors in the bottle and if you follow directions, exactly like the sample pictures.

 

If you want to make your own for the learning or for the pleasure, wonderful ... but it is not likely to save you time, trouble or money.

[Babs]

•  

Holly's Underglaze.

Cone 04-10

Ferro Frit 3124 33.3%

EPK Kaolin 33.3%

Commercial Stain 33.3%

Seive 80 mesh, ballmill 12 hrs.

Add Sta Flo LAundry Starch till mix reaches yoghurt stage then sieve again. Goes mouldy but maybe vinegar will help this. Another binder may do the job of the starch.

Some one may know the link.

from a previous post

This may be classified as a slip??? Perhaps the starch will work for you? Spray after you apply with soft drink??

[Min]

 

•  

Holly's Underglaze.

Cone 04-10

Ferro Frit 3124 33.3%

EPK Kaolin 33.3%

Commercial Stain 33.3%

Seive 80 mesh, ballmill 12 hrs.

Add Sta Flo LAundry Starch till mix reaches yoghurt stage then sieve again. Goes mouldy but maybe vinegar will help this. Another binder may do the job of the starch.

Some one may know the link.

from a previous post

This may be classified as a slip??? Perhaps the starch will work for you? Spray after you apply with soft drink??

 

 

This is the recipe from my posting (#5 in this thread).

I would add that ball milling any of the cadmium inclusion stains is a bad idea.

[Babs]

Sorry Min,

didn't go to the thread you posted just remembered an article by Holly in a daily newsletter from CAD, had copied it before and so posted it. Lots of work and research evident in the article but some people really get into that even when there is a reliable commercial product.

33% Kaolin  slip or not??

[Min]

Sorry Min,

didn't go to the thread you posted just remembered an article by Holly in a daily newsletter from CAD, had copied it before and so posted it. Lots of work and research evident in the article but some people really get into that even when there is a reliable commercial product.

33% Kaolin  slip or not??

 

Ummm, don't say sorry! 

 

I think the terms engobe, underglaze and slip are all a little muddled. If "it" can go on dry greenware or bisque I think of it as an engobe or underglaze, if it doesn't work on those then I think of it as a slip, If Holly's underglaze can go on dry greenware or bisque then I don't think the amount of clay in it is really relevant.

 

I was taught that if it contains less than 50% clay then it's an engobe, more than that then it's a slip. Don't know if those rules still apply?

[neilestrick]

The recipes for making your own underglazes will not work nearly as well as the commercial underglazes. Commercial underglazes are a pretty amazing thing: you can use them on wet, leather hard, bone dry or bisqued clay without flaking off, they are durable when dry, and they work with most glazes. To make a product that will do that requires a certain amount of additives, suspenders, binders and often some milling- things we potters don't generally have a lot of experience with or the equipment to do. So if you want your underglaze to behave like a commercial underglaze, it's probably not going to happen. But if you don't need that kind of flexibility in the product, like you only plan on using it on bisque, or only on leather hard clay, then go for it.

 

As for the recipe that's powdery when applied, it's because there's no clay in it to harden it. Gum solution will only go so far to make it harder. I would play with adding 2-3% bentonite or 5% EPK and see how that works.

[oldlady]

thank you all.  each of you has touched on at least one thing of value to my search.

 

I am not trying to put Mayco or Duncan out of business.  I am not trying to make a perfect opaque underglaze.  the recent article in pottery illustrated shows the watercolor effect that would be my ideal goal except that I am not a painter.  I would be proud to produce even one of the beautiful plates shown in that article.  we all need goals that are unreachable so we stretch harder.

 

I could not remember Sta-flo.  since I have all kinds of things on my studio shelves, I could not remember whether starch, Vgum, sodium methotrexate, glycerine, karo syrup or something else was what I was trying to remember from many years ago.  I only intend to use an ounce or so of color on each pot so I am going to try some of these suggestions.  mostly brushing tiny dabs of blended colors.  opacity is not my goal so maybe the word underglaze is misleading in this question.

 

as a second request, has anyone figured out how to reconstitute the dried lumps that commercial underglaze becomes if you leave it on a shelf too long? (one year)   The plastic bottles it comes in leak air and the material inside just dries up.  adding water simply surrounds the lump with water inside the jar.  shaking the results ends up with a lump inside water that has to settle back down to its original lumpiness still surrounded by clear water once it settles.  I almost want to store these 20 tiny bottles inside a bucket of water to prevent air from reaching the contents!  no wonder they are sold in 2 ounce bottles.  and yes, 20 bottles X $4 does equal an investment I hate to see wasted.

 

again, thanks to you all.

[Mark C.]

I do not use any of these stuff in this thread (no commercial galze/underglaze) but will add that a blender will in 2 minutes make those two hard oz be a nice blended one.

You just need a mini blender-then store jars upside down in a sealed plastic tub.

You could dry out the whole deal and hit it with a hammer then slake it back with water-use a mini electric drink stirrier to mix baby amounts

Mark

[bciskepottery]

I do not use any of these stuff in this thread (no commercial galze/underglaze) but will add that a blender will in 2 minutes make those two hard oz be a nice blended one.

You just need a mini blender-then store jars upside down in a sealed plastic tub.

You could dry out the whole deal and hit it with a hammer then slake it back with water-use a mini electric drink stirrier to mix baby amounts

Mark

The difficulty is 4 oz of dried underglaze will barely cover the blades in a blender, much less get agitated once you turn it on.

 

Perhaps water and a mini wisk, or water and then running it through a sieve.

 

Maybe add some glycerine to keep it from drying out once it is reconstituted. And, putting some saran wrap over the jar top, then screwing on the lid will make the seal more air tight.

[Mark C.]

(You just need a mini blender)

like in Barbies doll house

(mini electric drink stirrer)-these are electric and work well on small amounts.

mark

[Babs]

(

(mini electric drink stirrer)-these are electric and work well on small amounts.

mark

As if!!  Oh you meant underslip, sorry.

[Venicemud]

For years I have used the Mason Stain Co system that Vince described in an earlier response and you don't need to make up "gallons".  I mix up the dry ingredients  in an amount convenient for my needs and store in one container. I do add about 2% bentonite to this dry mix.  I mix up the wet ingredients - liquid CMC (either purchased wet or made up by myself), antifreeze and water, and store in a bottle.  I'm not as precise as Vince when making up the underglaze (sorry Vince but it works for me), I take a generous tablespoonful of the dry mix and a not so generous  tablespoonful of the stain and mix, then gradually mix in the liquid (giving the bottle a quick shake first) until I have the consistency that I like.  The wet and dry mixes can be stored for years - I speak from experience - and the underglazes made from them can, of course, be made up in larger batches if you are more productive than I.  I do feel that the underglazes are smoother if pushed through an 80 mesh sieve - that's the most time consuming part.  Joan.

[oldlady]

thank you, joan

 

I read the recipe Vince provided late at night and was struck by 5 gallon bucket, 12,000 grams and other terms that made me think it was not possible to reduce the amounts mentioned without a lot of math calculations.  now that I have read it again, I see that your suggestion is a good one and workable.  thank you

[kali]

borax.    Sodium Tetraborate.  my guess.

[Min]

27 minutes ago, kali said:

borax.    Sodium Tetraborate.  my guess.

Borax in the underglazes? 

[kali]

nope. replied to wrong query.. on wrong thread. and then it refused to let me edit i am now firing myself off to bed.  gah!

 

[kali]

the dangers of copy/paste, and over tired.