Multiple mediums & letting "wet" clay dry.

[DirtEater]

I've been playing with some WED clay and some Sculpey and have modeled a few things, but I've only been sketching, no commitment. I'm now at the point where I want to model some specific ideas for keeps, but have reached several dilemmas that I just didn't see coming.

I want to use wire, string, and tissue paper along with the primary medium of a water based clay for figures that would be about 2-3 feet in height, but I'm worried about how the clay will hold up if I just let it dry and seal it with something. Does anyone have any experience with painting and sealing dried "wet" clay? It seems to me that if I just coat it with enough shellac-type stuff then it won't matter what the clay decides to do, but I also won't always want that coated surface, it won't always fit the mood.

So with all this in mind and considering that it's important to me to keep the wire, tissue, and clay integrated, is there any reason to cast plaster from the clay elements when I'm not concerned with having more than just the original, and will the clay hold up on it's own if I allow it to completely dry?

[sculptor]

from my experience;

unfired waterclay will eventually crack and crumble

[bluedogshuz]

I agree. you could work with plaster direct. Model over wire armature then sand or use wood rasp. Also a cheap way is paper mache over styrofoam. You can create large objects quickly. Keep in mind that paper mache will shrink on the foam so make allowance otherwisw you will have warping. just some thoughts from experience

[fritchie]

I don't think there is any way to keep natural or "wet" clay in a formed condition, as you wish. Eventually, it will dry and crumble or powder. In fact, shellac or other coatings probably won't even adhere.

As bluedogshuz has suggested, you could use alternative, permanent materials, sculpting them directly into your final form. Plaster, or as he suggests,papier-mache over styrofoam. You probably could use a thin layer of plaster over styrofoam, also, to keep down weight.

[Merlion]

Relating to this topic, I notice this news article about a local sculptor who set up a stall in a shopping complex to sculpt quick clay portait busts of customers who apparently take them home afterwards. He can do them in half an hour.

In the online news article, photos are shown of life-size portrait busts of George W Bush and Mao Tse Tung he modeled with clay. The color of the busts is very pale grey.

I wonder what type of clay he uses.

I suppose it cannot be a water clay. As others here said, water clay scultpure models do get hard when dry. But they would shrink and may crack and break-up when they get dry.

Has anybody tried mixing water clay with paper pulp to reduce these problems?

Polymer clay can be hardened by heating in a kitchen-type electric oven. But I have not heard of it being used to model something as a life-size bust.

You can find the article and the photo here (http://www.sun2surf.com/article.cfm?id=12599).

[fritchie]

Merlion - Paper pulp in a water-clay would rot over time. Other materials, such as plastic fibers from "unwound" polypropylene or similar rope would not rot, but also would do nothing to stop drying, and probably would not help much with crumbling.

[Buster]

I know of a few people who do lifesize busts and larger in polymer. They use it mainly for modeling and then molding instead of using plasteline, but it could also be baked as the permanent medium. They use it because of its wonderful consistency, and also because some people (they) have a bad skin reaction to plasteline.
It is pretty expensive, compared to Wed clay, but you can build it over a heat-proof armature. All water based clays, unless fired, will remain extremely fragile dirt clods and are not suitable as a finished medium.
If making small statues, some people like to use MagicSculp and Aves epoxy. They are two part resin epoxy clays that when mixed together, will harden to stone in about 1-3 hours. Negative aspect is a short working time, so you can only mix as much as you can model in about an hour. No reason you can't use the stuff over filled out armatures (foam, wire, and plaster or FortonMG) - for the final 1/2 inch or less surface detailing. The epoxy should stick to the plaster.
The guy making water busts quickly for people to take home could be doing just that - and leaving it up to the customer to dry, fire, and finish the heads by taking them to some local ceramic shop.

[the2lees]

I work only in water-based clay and till recently kept only the unfired original for myself. With careful handling I still have pieces I made 15 years ago. I let the figures dry and repair any cracks that form, then paint it with shellac when it is completely dry. The key is to use a quality clay body and to watch out for thin areas like small arms, fingers, etc.

If the clay cracks (before shellac/sealing), I make a slurry of the same clay mixed with Elmer's Glue and fill the cracks, then clean it up. If this doesn't work and there is an area that isn't visible, I mix in torn toilet paper or tissues with the glue-slurry mix and apply it.

A word on armatures--if the wire you are talking about is on the inside of the sculpture it will be more likely to crack around the wire as it dries. If you want to experiment, you can try mixing Elmer's with the clay that will be touching the wires/armature to see if this helps.

Candice

[the2lees]

Also, "claystone" is a water-based clay made by Sculpture House- google for it--that is made to air-dry hard. The MSDS says it contains wood pulp and lignosulfats, which, interestingly enough, is like my homemade toilet paper and glue binder.

Candice

[classicalsculpt]

You can if this applies to your project, or future projects, do a traditional waste mold in plaster from the wet clay model to get only one figure. Just keep the clay model covered and wet until you are ready to cast it in plaster or whatever material, and the cracking won't be an issue. Make sure you get clear instructions on how to do this right. Also you can take the plaster figure from that and use it as a master model for any additional piece molds (such as a latex and plaster mother mold) and multiple casts in the future.

A good book that shows step by step how to do traditional techniques in this is "Moldmaking, Casting and Patina for the student sculptor" by Bruner Felton Barrie

The posts above use more modern techniques, and may be simpler to do. Some molding techniques now adays may be easier to use, yet more expensive. But if you are like me, and want to use natural materials, this is another option.