Monday, September 5, 2011

Standing On The Shoulders Of Giants

Each and every doll maker will eventually develop their own path.
Even Martha Armstrong-Hand suggests trying several different ways.

1. Drawings. Her final working drawings included shrinkage adjustments.
She made a materials shrinkage chart including shrinkage for many materials.

2. Armature and Modeling Stand. She made her armature according to the
final working drawings, so shrinkage was taken into consideration.
Her modeling stand was constructed from pipe fittings, which allowed
her to unscrew the finished sculpture from the modeling stand for molding.

3. Modeling Clay. She modeled oil-clay over the wire armature. She used
traditional methods to model the clay original. The original clay has
all the surface forms modeled as close as possible to a finished sculpture.
The oil-clay is reusable.

4. Remove Clay Sculpture and Cut. She removed the original clay on the
armature, from the modeling stand and cut it at the limbs and head.
She had six modeled oil-clay parts: torso, head, arms and legs.

5. Waste Molding. She made plaster rough shell molds of the six parts.
The plaster and water were mixed using the dry-lake-bed technique.
She saturated the plaster molds in water to cast carving wax.
This is where I make hot-pour moulage molds, in order to save plaster.
The hot-pour moulage molds do not need to be saturated in water.
Also, the hot-pour moulage molds can be reused after casting carving wax.

6. Casting Carving Wax. Martha used her own studio formula for carving wax.
She had very specific materials properties that she looked for.
She used a paraffin wax that had a melting point of at least 160 degress F.
She used an industrial talc that is almost as fine as talcum powder.
She used bleached beeswax.
The carnauba wax she used was obtained from a candle making supplier.
The formula she used, measured by weight is:
9 parts paraffin wax
9 parts talc
1 part beeswax
1 part carnauba wax

Use a thermometer when melting wax and never let it get over 185 F.
Do not breathe any wax smoke (it is too hot if it is smoking).
Always pour melted carving wax into water-saturated plaster molds.
She says that her carving wax shrinks 2%.

7. Wax Work. Martha used a wax pen, various metal dental tools, and sandpaper
to work the carving wax parts. She has six carving wax parts at this point.
All the carving wax parts are cut at the joints. Balls are cast and added.
Legs: upper legs, lower legs, feet.
Arms: upper arms, lower arms, hands.
Head: head.
Torso: upper torso, middle torso, lower torso.

She liked to keep carving wax at no hotter than 155 F. for adding to the parts.
Sandpaper is the final tool used to finish the carving wax parts.
Sandpaper grades used: 80, 100, 120, 240, and 280. For the finest finish: 600.

The actual work is practice, practice, and more practice: adding, subtracting
and smoothing repeatedly. It is during the wax work that the joints are
designed, tested, and improved, until every joint works as it should. Details
can be carved in the carving wax that are extremely fine. Eye position is
essential for the doll to come alive and look at you. Experience cannot be
read in words, so it all comes back to practice ,practice, and more practice.

Martha says that most beginners want to start working on the face right away.
The best place to start working with carving wax is the back of the skull, or
on a carving wax spare that was trimmed off. Get used to adding and subtracting
carving wax, and welding it to other pieces. As you gain experience, then you
can work on the delicate features of the face, and so forth.

8. Body Works and Stringing Design. Since you must design the joints and test
them in carving wax, this part should actually be done during #7 (Wax Work).
Martha made ball molds so she could cast balls in wax, ready to weld to an
arm or a leg. After deciding on ball and socket size, it helps to focus on
one thing at a time. For example, work on a shoulder joint with concentration
until you like it, then see how it works. Duplicate it on the other side.
Check front and back posture, then look at the rest of the body so far. How
high or low are the shoulders? How broad are they, and do they feel right
for the age of the person? Maybe the neck should be longer or shorter? Try
to research one problem at a time. Look at people or your photos for reference.
Study and practice until you gain experience. Experience is what you get
when you are looking for something else.

The nice thing about carving wax is that if you made the carving wax parts thick
enough, they will be strong enough to test string, using elastic or springs. It is
at this point in the process that you have created the complete BJD in carving wax.

You'll probably have holes and slots cut in the carving wax parts, and those will
need to be filled before the final molds can be made, otherwise the hollow parts
would fill up with the final mold material.

The final mold material can be plaster for making porcelain slip casting molds,
or silicone rubber for making resin castings. You use the refined carving wax as
patterns for making the final molds.

So the materials used are: oil-clay or polymer clay --> carving wax --> porcelain/resin
The molds used are: plaster or moulage waste molds --> final molds
Shrinkage of materials:
oil-clay or polymer clay (0%);
carving wax (2% to 3%);
porcelain (16% to 18%);
resin (0%).

If you have taken care to model the original clay very close to what you want,
then you should not have to make more than one carving wax casting, and that
carving wax, once refined, should not have to be waste molded again. You should be
able to make your final molds from the refined carving wax patterns.

Martha made a small Carving Wax Test Doll when she first decided to make
ball jointed dolls. She used the Test Doll to try different joint design things.
That is what my Carving Wax Test Doll is, just a test dummy. She is a part of my
process of making Aalish, but Carving Wax Test Doll will never have a final mold
made from her parts, or anything else. I am learning how to work with carving wax
using her.

I appreciate Martha's Method more and more, the more I work with carving wax.
After looking at so many work-in-progress threads at various forums, I can see
that, for me, following Martha's Method is the way I want to go, after I finish this doll.

I like the reusable oil-clay modeling material, reusable moulage, and reusable
carving wax, which can be used for test stringing a doll, as well as being refined
for making the patterns for the final molds, whether for casting slip or resin.
Martha Armstrong-Hand was an amazing doll maker.

Many doll makers at various forums, use non-reusable modeling materials.
Apoxie Sculpt, Polymer Clay, and Air-Dry Clay are all non-reusable for the most part.
However, they do not need to be waste-molded because they are all strong materials
that can withstand test stringing, and can be final molded when finished. Some of
them need to be sealed before they can be molded.

Plaster is a relatively inexpensive molding material, compared to silicone rubber,
but plaster cannot be reused, even though it can be stored, and used as a mold again.
Plaster mixed using the dry-lake-bed technique does not last for very many castings
before it starts to lose crispness, and starts to disintegrate.

Old silicon rubber molds can be chopped up into small cubes and reused for waste molds.
This technique, described in Tim Bruckner's book, Pop Sculpture, requires that you
have some old molds on-hand in the studio, some fresh silicone rubber, an air
compressor, and a pressure pot. Carving wax may be poured into the waste molds.
This method of using cubes of old molds is not used for the final molds.

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