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[Ricardo Pontes]

Im wondering what are some techniques to start dong larger clay works. I generally do pretty small stuff that fits in a kiln. But what if i wanted to sculpt things that were 50" tall etc.. All that clay would weight a ton, even if it was hollow.

Do sculptors start out by using paper,a nd just put it on the inside? Or some other method. how do you keep the sculpture from dripping and sinking?

[Stuart]

First you build a sturdy armature (basically a metal skeleton) on a strong wooden base. (revolving is best if your space is limited) ....and there are examples here on the forum ............I'm sure Heidi will supply the links. These can be welded or constructed from a system called KeeKlamp (available in the UK and USA.) The latter, supported from the outside usually.
Then you create your general bulk with 'chicken wire' and stuff the iside with old paper or even lighter polystyrene blocks. Paper is actually better though because you can soak it with water, which forms an internal damping system, once the clay is on.
To keep the exterior damp, spray with water and cover with damp cloths and then plastic each time you finish work for the day.
Be sure to use 'butterflies' to hold the clay at various points.*

Your head or other detailed areas can be removable to allow you to work on them seperately, thereby not leaving your main structure open to drying out.

Downside with wet clay is the weight. You've got to be sure of your floor!

Upsides........MUCH faster, and.......gives itself more readily to expressionistic surface handling...........or super smooth with a sponge!
You can even polish it when it gets leather hard if you like that kind of thing! Very physical, very expressive, and a lot of fun and easier to alter. No spirits needed to smooth surfaces.
Extra requirements: Bins to keep your clay moist, cotton cloths to do the same (old sheets) and lots of patience when building a carefull, well supported armature.

* butterflies* small pieces of wood placed in a cross fashion and wired together, then suspended securely from your armature at different points. Pack your clay in around these.
Stuart

[Tamara]

Ricardo,

I too been considering life size and how to do it in clay. One thing I'd like to try is paper clay. I have used home made paper clay to repair areas that need strength but I'm talking about using the manufactured kind that is evenly dispersed paper throughout.

Benefits are that paper clay is a lot lighter after paper burns out (not sure if it's lighter while in the green/unfired state). In the greenware stage, the clay is much stronger (and maintains strength even after firing) and thus, I've heard, life size works can be done without an internal armature. It's strength is greater so that arms can hold the weight etc,etc.

I printed out for my own records this article link below. Ian uses bubble wrap for the inside area and sometimes uses aluminum (light in weight which can burn out in the kiln.
http://www.ian-gregory.co.uk/paperclay.html

On larger works- I'm guessing that the paper fiber wouldn't cause surface problems(bumps etc.). If doing rough surface texture then would be okay to have a little fiber in there.

I'm thinking of using it when I do quicker sculpts that take a month or less to do (reason-rotting paper won't smell well

Stuart- What do you think of paper clay?

If the life size work will be fired rather than cast i.e. in bronze, then a big enough kiln is necessary.

I've been looking at Oval Olympic Kilns 3031HE which is 30 X 42 X31.5 "
http://www.bigceramicstore.com/Supplies/kilns/Olympic_oval.htm

Need to see if the kiln is capable of breaking down in components and remove the rings/walls so that the sculpt can simply be set on the bottom of the kiln- then put the rings back on.

Life size works can be cut in half and have registration protrusions to reassemble (possible glue?) after firing.

I'll probably only go on up to half life size for starters .

~Tamara
_________________
Happy Sculpting!

[Stuart]

I'm sorry, I have no knowkedge of this medium, but it sounds really interesting!
S

[Chuck Williams]

Back in the theme park days we would rough sculpt the form in foam and cover it in a layer of water clay about an inch thick.

On large pieces, the foam blocks were foamed in place around a welded steel armature. Some of them had tabs to help support the foam on very large pieces. Smaller pieces of foam were just shoved on a metal pipe or spike.

The largest armature I ever worked on was made from an aluminum antenea tower around 35 feet long with a steel center post. It was held up on either end with welded steel "T" frames on wheels and the center post revolved on a huge bearing.This was covered in foam and then water clay.

Now here's where young and reckless part comes in!
We made a plywood wheel on one end of the armature and attached it to a table saw motor with a speed regulator.
We got the thing rotating at a good speed and I "turned" it with a custom fabricated steel tool! Made a beaultiful tapered foam armature for a giant redwood tree.

The foam was then shellaced. I drove large wooden "stir sticks" in all over it to help grip the clay.
I also used an open weave strip of nylon fabric to wrap the clay periodically as I was building up to help support the weight since the whole thing was on it's side.

To give you an idea of the weight of the water clay,I slapped on a skin about one and a quarter inches thick, one third of the way down the length and all the way around this six foot thick "tree" and had gone thru one ton of clay before lunch.
After lunch I continued skinning it with clay when the steel pin locking the whole thing in place was sheared right thru and the whole thing started spinning!
Well as you can imagine, the water clay started peeling off this thing and flying all around the room.It looked like I had just skinned an elephant!

A good sized chunk landed right on the foot of the owner of the company! After the shock of what just happened faded ,I looked at him ,picked the chunk of clay off his foot and said "Well,you don't see that everyday!".

Spent the rest of the day shoveling clay onto a plastic sheet.

Big stuff can be fun!
Chuck...

[Tamara]

Wow! Quite the story. Enjoyable to hear your experience with working with life size and then some!

Clay sure is heavy. A ton of clay! Lots of work you did and then have the whole thing spin the clay off. Sounds a bit fun! A mud bath of sorts.

Neat how you turned the tree with cleverness.

Thanks for sharing,

Tamara
_________________
Happy Sculpting!

[Chuck Williams]

Thanks Tamara,

I felt like I was rambling a bit.
Glad it made sense!
When I was done with that piece, it was covered in two and a half tons of water clay.
It was different, that's for sure!

Foam , any kind of foam, over a sturdy wood or metal frame makes a great lightweight filler.

I like Stuart's set up very much because it allows you to really work the sculpture in scale and make adjustments.
In that set up, foam strips could be attached in the long bones of the legs and arms,a good sized chunk in the chest,hip and head areas.

For a life sized torso I used 1/2" plumbers pipe in a narrow, upside down "U" shape and filled it with blue foam from the hardware store.

A covering of fabric or scrim dipped in plaster holds it all together and gives a nice surface for the clay.
There are new liquid plastic coatings for foam on the market but I haven't used any yet.

Keep in mind that if you change your mind about something or want to tweak the pose, you want something that can be altered on the fly.
Plaster over foam is great because you can use a hammer to literally knock down the surface of the armature.

Chuck...

[Heidi Maiers]

That's a hilarious story Chuck - although you probably weren't doing much chuckling at the time!
Great info in this thread.
I would think that in nearly all cases of working this way in water clay would be intended for molding only, not firing. But if one was clever enough to remove the clay from the armature in sections and fire them, then reassemble and repair/reinforce, I suppose it would be possible.
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[Chuck Williams]

Thanks Heidi!

I was more happy I wasn't killed than angry!

You have an idea there.

There must be a way because I just remembered the terra cotta soldier sculptures in China.
Were those each sculpted separately or slush cast and fired? Either way a look into those may give some insights.

I suppose you could sculpt a lifesized figure in smaller stacking pieces.

Back in the day in Japan at least,I know that enormous kilns were built on hill sides and a years work would be fired at one time.

Could be a very interesting end result!

Chuck...

[Tamara]

Looking at Ricardo's initial comments, looks like he's asking about fireable larger work techniques. However, he may realize that life size work is most often converted into another medium. I personally haven't seen many clay full body life size works. Definitely need sections for that! Or some great technique that I'd love to know about!

The bubble wrap on the inside can be reduced by poking a skewer in and popping some bubbles to adjust that type of internal armature. It will burn out in the kiln.

Ricardo- to keep things from sagging, like an arm, can prop it up with a large coil of clay (which will shrink at the same rate as the sculpt) or a piece of wood but this needs to be removed as the sculpt shrinks or it will create a stress line probably at the arm pit area.

~Tamara
_________________
Happy Sculpting!

[Ricardo Pontes]

[Heidi Maiers]

A wood armature might work, taking in some considerations. Because wood is dense, it wouldn't shrink while the clay dried and therefore the clay would crack and fall apart all around the wooden armature. If, however, you applied a very thick layer of wet newspaper over the wood and used masking tape to secure it, and then applied the clay, the wood would support the wet clay and when drying, the newspaper would provide enough cushion so that the clay had room to shrink without breaking apart.
When firing, it would be best to remove the wood, if possible, and just leave the newspaper to burn out. If not possible to remove the wood, at bare minimum, it would need very good ventilation system (think lots of holes) to allow the smoke to escape - or the piece will explode in the kiln.
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Heidi Maiers
Forum Owner
If you learned something here, consider donating to the COFFEE FUND!
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[Seb]

Hello everybody.

Heidi, last week a potter said to me that it was very dangerous to let a wood armature, or ever newspaper in an electric kiln... he said it's because electric kilns don't have ventilation nor flame inside during the firing process. So a volume of gaz builds and might eventually explode.
I don't really know what to think because I fired a few sculptures without wood armatures, but there were newspaper inside. I always keep a vent open on the top ( it's a small hole one inch or less in diameter ), and you can smell the fumes in the room where the kiln is...so I think smokes and inflamable gaz find their way to escape.
Is it dangerous to have a wood armature in an electric kiln.... if yes, I might consider using metal or someting at the core, but still want to use newspaper cause it's easy and cheap.

It's fun to see we all want to add finer and finer shapes ( arms , fingers... ) as we improve ^^
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[Christine Towers]

Having just posted my first post ever on the Work in Progress bit, I've just now read this discussion on armatures for larger sculptures - my work in progress is currently 46 inches high and I'm building it round a beanbag armature.
I made the beanbag to the rough shape I wanted my figure (it's a traditional style statue of St Hugh of Lincoln for a local church) and once filled, I gathered the top and suspended it from my studio rafter. I built the figure using fairly chunky extruded coils - heavier at the bottom.
When thoroughly filled, the beanbag gives good support - I have experienced slight sagging at the bottom, but have easily corrected this by adding more clay - it could just as easily have been righted by adding a temporary external support. I have also been able to remove some of the beans (using my vacuum cleaner!) from the top of the bag to narrow the head section which was looking a bit too deep front to back.
I hope you find this interesting.
Thank you for a brilliant resource
Chris