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Ginny C

Simple Wadding For Supporting Pots In Electric Kiln Glaze Firing

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I have some very narrow little vases I'm going to glue to a separate base, also glazed, AFTER they are all glaze fired. I'd like to glaze them all the way down, so I will need to support them during the glaze firing, and I don't have small enough supports. Can i make wadding with just my regular B-Mix (cone 5) clay with maybe some sand wedged in?

 

I plan to glue the wads in place before placing each vase in the kiln. I don't have any of the usual suggested ingredients around, but I do have some sand!

 

Suggestions? thanks!

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Shrinkage on a narrow base is insignificant. But the words "very narrow" are also very relative.

 

Do the vases stand up on their own??

If yes, just have them sit on an extra layer of kiln wash-- on a broken bit of shelf if you have one. If there is space to put a ring of clay under them, that would work as well.

If no... well... they are going to topple.

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can you get you hands on some shells? epk, fire clay? commercially made stilts?

 

have u seen the technique for crystalline glazes?

 

not tested @ 6  but similar to wood fire wadding.... (volume)

3 grog

3 clay (high fire/fire clay)

3 sawdust packed

1 sand

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when I made macro-crystalline glazed vases I learned the hard way that shrinkage was very significant. The practice back then (1971) was to high temp bisque to avoid it. When I was first experimenting, I had pieces fall over from the movement of shrinkage. The caustic glaze ate a 3 inch hole in the brick! Always use caution.

Marcia

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Ahh. Neil's answer is helpful. Always nice to know the WHY!  But I don't know if sand is "more refractory" than my clay...

The skinny little vases are only about 1 1/4" or 1 3/4" in diameter (and about 4-5 inches tall), so they do stand up but not very securely.  (They will be glued to a base after the glaze firing, so they don't need to be very stable on their own.)

 

They are made of B-Mix clay which is what I would make little wads of.  I guess I will coat them in kiln wash before gluing them on the vases. The reason for putting something under each is that I am glazing them clear down to the bottom.  I DO have some stilts but not enough of the very small size I need for these. 

 

I'll be firing these tomorrow so I'll report on the results after that!

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Marcia:

It is 2016 and that part of crystalline has not changed since 1971. 50% alumina / 50% EPK is still the standard wadding as well: as John has pointed out. This mix will hold it in place: and the unequal COE will make it release easily.

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Success, but actually didn't use any wadding.  I discovered that the little vases fit on top of my 1 inch shelf stilts. After glazing each I glued them each to one stilt.  A few didn't stick but it didn't matter after all. It was easy to set the stilt where I wanted it and just set the vase on top. None fell over. I will now try to attach some photos. One of them ready to go into the kiln and two after the firing. My husband epoxied them to the base and I used them for a special breakfast for friends this morning.

post-1066-0-90675600-1460408507_thumb.jpgpost-1066-0-98534400-1460408550_thumb.jpgpost-1066-0-44561000-1460408571_thumb.jpg

Hmm. Is there a way to rotate a vertical photo??

 

 

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post-1066-0-98534400-1460408550_thumb.jpg

post-1066-0-44561000-1460408571_thumb.jpg

MatthewV likes this

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glad you were able to fire them successfully.  are those tulips out already??  in indiana?   HOORAY spring must be on its way.

 

(those are posts under your vases.  stilts are some small shape or a bar with wires sticking up to hold lowfire work off the shelf so the bottom can be glazed.  stilt marks are those tiny blips of unglazed  clay you sometimes see on lowfire wares.)

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Thanks, Doris! And thanks, Old Lady, for clarifying posts vs stilts for me!  (I bet I'm older than you are...) I do have some stilts but they were not quite small enough for several of these skinny vases.  I have used them frequently under my mid-fire (cone 6) pots. Didn't know they were only for low-fire. I use them just in case of glaze running...

 

Actually, I bought the tulips at Kroger's! But our daffodils are blooming.

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The 50% alumina / 50% EPK wadding mix has been a revolution for me in the ease of packing my kiln! I roll it out and cut into small squares and dry. Hot glue as many of them as needed to the bottom of the pots and fire! And they are reusable!

JBaymore likes this

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Hi, I  am new here and not sure how to post my own questions in a new forum. There doesnt seem to be any link to start a new forum question.

 

I have question on wadding. My boss uses a wadding mixture of 50 parts EPK and 50 parts ball clay that is mixed together with water to create a dough which we then use to put between the kiln furniture and shelves to act like a glue so that as we are building up the each shelf it is sturdy.  Do most people do that or is it not necessary?

 

My other more important question is we have a bag of Kaolinitic Clay powder which I know is an ingredient in EPK, but I need to make more wadding and and we do not have any more EPK. Can I mix 50 parts Kaolinitic clay powder and 50 parts OM4 Ball Clay and maybe throw in  alittle Alumina to make wadding for the glue part of our shelf making? 

 

FYI this would be for an electric kiln......

 

Any advice would be much appreciated :)

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Hi, I  am new here and not sure how to post my own questions in a new forum. There doesnt seem to be any link to start a new forum question.

 

I have question on wadding. My boss uses a wadding mixture of 50 parts EPK and 50 parts ball clay that is mixed together with water to create a dough which we then use to put between the kiln furniture and shelves to act like a glue so that as we are building up the each shelf it is sturdy.  Do most people do that or is it not necessary?

 

My other more important question is we have a bag of Kaolinitic Clay powder which I know is an ingredient in EPK, but I need to make more wadding and and we do not have any more EPK. Can I mix 50 parts Kaolinitic clay powder and 50 parts OM4 Ball Clay and maybe throw in  alittle Alumina to make wadding for the glue part of our shelf making? 

 

FYI this would be for an electric kiln......

 

Any advice would be much appreciated :)

 

 

Welcome,

 

Top right corner of the main forum section page is a black button that says "Start New Topic"... Click that to cerate a new thread.

 

Using some wadding mix on shelf posts in any kiln is certainly a good way to make a stable load and get things really level.  In smaller kilns, unless the shelves and/or posts are pitted and/or warped.... it is probably a bit of "overkill".   For a soda, salt, or wood kiln........ it is pretty much a necessity to keep the posts from sticking to the shelf bottoms. 

 

In a larger electric or gas kiln (say maybe 40+ cubic feet) not a BAD idea to help make the load more stable.  In a 7 cubic foot hex electric.... with maybe a stack of 5-6 shelves tall at most........ probably not necessary at all.  But will not HURT anything.

 

"Kaolinitic Clay" as a term (unusual) basically says it is something that is more or less a kaolin.  Mix that 50% with 50% alumina hydrate... and you have "kiln wadding".  Any kaolin with 50% alumina hydrate will work as wadding pretty darn well.  In fact,...... for gas and electric high fire...... 50% kaolin and 50% silica works OK.  Or 33.3% any kaolin, 33.3% alumina hydrate, 33.3% silica is a pretty standard kiln shelf wash mix that makes a good (non woodfire/salt fire) wadding also. 

 

best,

 

................john

High Bridge Pottery likes this

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