Paper clay majolica

[docweathers]

I'm trying to push the boundaries of typical majolica by using cake icing piping tools. It all works pretty well except on larger decorations the cake icing is inclined to crack as it dries. At one level I have solved this by putting in a little cellulose like you do with paper clay. This works pretty well except for one hangup.

The bits of cellulose  tend to clump together and make it hard to extrude the majolica. I've tried putting the raw cellulose in a food blender and running it for quite a while to get it chopped very finely. This helps but there's still a problem with the clumping. 

Any suggestions would be appreciated

[Bill Kielb]

I have to ask my wife, I think she is a fan of very thick slip prepared with Darvan to make it reasonably dense then flocculates what is to be used just prior to using so it becomes a smooth sticky paste that she can pipe on the surface. I think she prepares the slip this way so it is maximum density,  minimal water which makes shrinkage and cracking more tolerable. She does incredible cake decorations with the real stuff as well! Yum!

[Min]

Fish Sauce Slip works even when really thick. I'ld mix up some with minimal water so it's thick to start with then add a tiny bit of Darvan to deflocculate the slip then work more dry Fish Sauce Slip into the slurry. Get it piped onto the pots while they are still as wet as possible. John Britt video on deflocculating slip here.  If you want to keep the Fish Sauce Slip really white then sub 5 macaloid for the bentonite. (you can also add zircopax or stains to the slip to opacify or colour it)

Fish Sauce Slip ^04 -  ^10  

• Kona F4 23.5%  (or Minspar)

• Grolleg 43.6%

• Pyrophyllite 7.8%

• Bentonite 9.5%

• Flint 15.6%

[docweathers]

There are a number of types of Pyrophyllite. What kind should I use in this fish sauce slip? what kind should I use in this fish sauce slip?

[liambesaw]

10 minutes ago, docweathers said:

There are a number of types of Pyrophyllite. What kind should I use in this fish sauce slip? what kind should I use in this fish sauce slip?

Give it the ole eenie meenie minie moe

[Min]

13 hours ago, docweathers said:

There are a number of types of Pyrophyllite. What kind should I use in this fish sauce slip? what kind should I use in this fish sauce slip?

I've only ever seen 1 choice at the ceramic supply places. Where are you ordering from? 

[docweathers]

I was ordering from US pigment.  They have a couple different kinds.  I think I'll try my local supplier since it cost more to ship the stuff than the purchase price.

[docweathers]

On 2/21/2019 at 2:38 PM, Bill Kielb said:

I have to ask my wife, I think she is a fan of very thick slip prepared with Darvan to make it reasonably dense then flocculates what is to be used just prior to using so it becomes a smooth sticky paste that she can pipe on the surface. I think she prepares the slip this way so it is maximum density,  minimal water which makes shrinkage and cracking more tolerable. She does incredible cake decorations with the real stuff as well! Yum!

Did you ever check with her?

[Bill Kielb]

I did and as mentioned she adds clay and Darvan blends in as much clay as possible with least amount of water and keeps this as her base slip. When ready she removes some, flocculates with  concentrated epsom salt and whips to a very creamy frosting like texture and pipes away. Simple, actually

[docweathers]

thanks