mica for putting your witness cones in.

[CaroleLagace]

con someone tell me where to get the mica for mixing with clay to make the little stands to hold your witness cones in. also what is the ratio for mixing? oh yeah, I live in North America

 

 

[liambesaw]

What is the purpose of that? Very curious

[Hulk]

Hi Carole!

The instructor (and lab techs) at the local JC scoop lightweight granulated material that the cones are packed in to mix with clay to hold cone packs; I'm guessing the packs dry faster with the addition, and if not fully dry when pressed to service, quickly dry out as the kiln heats up.

I use a thin ribbon of clay, just enough to hold the cones; I'm turning the edge up for a bit for strength. So far, my lil' cone packs aren't breaking or blowing up. 

Where/how to find the material, not sure 'bout that; likely vermiculite, which I'd stay away from, generally, as there may be asbestos, right? Would not grog (perhaps even green clay granules) serve same?

Try searching "vermiculite for cone packs" and "cone packs"

[Mark C.]

Vermiculite which is mostly mica can be bought at a building supply place (not sure about big box stores)

It used to be an asbestos issue but now its not .Sheet mica is found at rock shops but that not what you are looking for. Also Garden supply places sell mica (vermiculite is the name you are looking for)as a soil moisture product.

[Hulk]

,)

More, includes pics of Mark's cone packs

http://community.ceramicartsdaily.org/topic/6923-making-cone-packs/

[Hulk]

Looks like a s'more! ...now me hungry, must smash snack

[neilestrick]

Just make your cone packs out of your regular clay and poke a bunch of holes in them with your needle tool.

[liambesaw]

Oh so it just helps dry them faster?  I made a fixture out of slices of soft brick so I can reuse it because I kept forgetting to make them up ahead of time.  Neat.  Never heard of vermiculite referred to as mica.  When I hear mica I think of the glittery powder.

[Russ]

They have mica online at new mexico clay.  it's mined here in northern new mexico.

[Mark C.]

Liambesaw

Cones used to come in this vermiculite mix in the box before foam.I still have boxes of old cones with this in them.

When you wedge it into cone packs it can be fired very fast without exploding.

It helps as Neil said to poke holes in the clay to make them dry faster-

This whole subject is for last minute get the cones in and fire NOW-I find it way easier to plan ahead and make up 6-8 cone packs and dry them well.

If I have to fire cones NOW then I wedge vermiculite into the cone pad clay-it has not happened for me in a decade.

[Bill Kielb]

Since the studio stopped using a cone boat for beginning reduction ( they start at 1500 F degrees because that is when their oxides begin to melt regardless of heatwork)  and they exclusively use self supporting cones there has been little cone pack drama to speak of.

If you can wedge some large particles in it allows your freshly made cone pack to dry more quickly and not explode. If you poke holes in it with your needle this helps as well. 

when it comes down to it we have our firing teams candle  (pilots only, minimal blower) their kiln  till about 250 degrees so the removal of all water at this slow speed almost guarantees that anything in there will dry slow enough to not explode regardless of the clay they use for cone pack, boats, etc...  

Fortunately with the use of self supporting cones we no longer have a need for cone pack drama.

[Mark C.]

(cone pack drama.)  it all can all be avoided by making them ahead of time and drying them out.For example make 6 pads today and put in warm dry place-drama is over. when you use 4 of them make another 6 of them again-Thinking ahead its easy.No need to poke holes or use mica.Like gas in your car you put it in before its needed.