Advice: Working With Porcelain Slip

[petawb]

Hello there everyone! First post from a porcelain newbie.

 

Tell me if I'm being ambitious here, though I'd like to undertake a process of creating many super thin 15-20cm long porcelain feathers for a project.

 

I've only ever worked with stoneware, handbuilding with slabs and pinch pots, I've never used slip before - so this will involve a lot of first time experiences for me.

 

I'm trying to plan out how I'll make these forms, preferably double sided.

 

I have access to a kiln a few months from now, so will be able to do some home experimenting (though I'm a total novice in that regard, so I'd probably want to fire them with my local studio instead - however they only do mid-firings, so not sure if I'd be able to)

 

Regardless, I'm happy to make the greenware and store them until I can get access to a kiln.

 

So here are my ideas, let me know if they spark anything in your mind and you can give me any advice/tell me that it's never going to work 

 

First idea:

 

On a dampened plaster slab, using different nozzles on slip trailers, I pipe out the stem and an outline of the feather shape, with none of the feather 'prongs' (?) touching each other, leave to dry for a few minutes:

 

(Sorry in advance for my terrible MS paint skills)

 

Once the first piping has dried a little, I pipe out a second layer of 'prongs' and repeat this process until there are no gaps to achieve a 'feather like' texture:

 

 

I then finish it by piping out another stem on top. Leave it on the plaster slab to dry, then peel off?

 

Second idea:

 

Buy feather silicone moulds used for cake decorating and create plaster slump moulds from them:

 

 

The trouble with this idea is that the feathers would only have texture on one side, do you have any ideas on how I could make double sided versions?

 

Third idea:

 

Scrap using slip and use a plastic porcelain instead, roll it out thin and cut out leaf/feather shapes before applying a texture to each piece. (Time consuming?)

 

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Ultimately I'd like to make 60-70 pieces to start with - and maybe more in future if it all turns out well, so efficiency is important to me.

 

I like the first idea the most since it would make every piece unique, though if you don't believe it would work, let me know as while I'm happy to experiment, everyone's previous experience and knowledge is a fantastic gift and it'd be a shame to waste it

[Pres]

A few more thoughts about your cake form molds. You could press mold clay into them, then after removal slap/stretch the pieces on a table top to lengthen and thin the feathers. Then join two together back to back. Another thought using that form is to make a new plaster mold for pouring slip into the form to get a complete feather. This could actually be a mold with several feathers in a row for forming at once, much quicker than by hand.

 

best,

Pres

[Mark C.]

I'm with Pres make a clay feather and make a mold from it then after a few positives you could make some molds with several in each mold depending on how many you need. Just remember they shrink each time.

[petawb]

Thanks so much for the speedy replies!

 

Yeah, it'll probably be easier to make in stoneware for me, then create a mould - though I'm worried about getting it thin enough for my desired effect. Looking at the fine print on all the feather silicone moulds floating around, there's nothing over about 10cm, so I'll probably have to make my own moulds since I wonder if I'd be able to stretch them far enough.

 

So you reckon the slip on plaster wouldn't be worth it?

 

Cheers again!

[Tim T]

If you want to make them really thin, you may want to use paper clay slip, and brush on 3 or 4 layers of this to whatever you use as a mould - this will be a lot stronger for handling before firing, and also avoid any shrinkage/cracking problems. I've played with using this to brush onto leaves, leaving the clay on the leaf and letting it fire out in the kiln so there are no problems with undercuts etc.

[Chris Campbell]

I would use any handy clay to make about ten to twelve different flat feathers with the detail and texture on each side.

* Note - make them at least 15% - 20% bigger than the size you want your final product and exaggerate the details.

I would let these dry then bisque fire them.

 

When dry I would begin to make molds of both sides of them with plaster ... Just line them up and make a long mold of one side, then the other side.

Take one of these molds and make a negative mold of it.

*Note - you need to be very precise with these molds so the two finished molds line up perfectly.

 

So now you have a positive and a negative to press thin clay between to get your feathers.

As you remove the feathers, you can bend or twist them to make each one unique.

[EdptrKrmk]

Hi ! For super-thin porcelain, you could maybe use Keraflex porcelain sheets (http://www.kerafol.com/en/porzellanfolie/keraflex.html) and a water etching technique (wax, water, sponge). Let me know if you try this out. I'd love to see a picture.

Good luck

Emma