Chapter 2: The Facts of Life(Casting):
Comparing apples to apples, not apples to oranges.

An artist that creates in 3 dimensions is referred to by the genderless term; sculptor. There are two traditional methods employed by sculptors;

1. Carving reduces some raw material, like marble or wood from a raw, native shape into the form envisioned by the artist.

Carving is subtractive.

2. Modeling builds up a medium like clay, wax, plaster (or even legos) from smaller portions into the desired shape. In this sense an architect, who builds up from portions of wood, concrete, steel and glass, is a modeling sculptor.

Modeling is additive.

Lifecasting, despite its ancient roots is a new approach made possible by contemporary materials. In one sense, the lifecast artist bridges both categories.

Lifecasters model natural forms into the position desired and frequently carve the final elements of their work.

In another sense, lifecasting is unique unto itself, like photography is to the 2-dimensional art world. It neither subtracts nor adds but, seeks to capture nature's movement to admire its transient, static form. No other practical, art technique can yet match the exquisite detail of nature's forms thus frozen in time.

Measurement Systems:

It is usually easier to just do a basic LifeCast™ project than to explain all the reasons for why it has to be done in a certain way. However, it is important that you understand both how and why things work to be truly creative and persue more advanced visions.

The following principles are already "built in" to the step-by-step instructions of our BODY PARTS™ kits and everything is already pre-measured for you. In the other products you must do the measurements for yourself.

There are two distinct ways to measure the LifeCast™ mediums. They must not be confused and you should avoid combining them in a single project.
• Weight: How heavy a thing is regardless of how large (the volume) of it is.
• Volume:- How big a thing is regardless of how heavy (the weight) it is.

In one, very special case the same volume is always the same weight (at sea level). That is why water is the scientific standard for "specific gravity". One cup of water (8 ounces by fluid volume) is also always 8 ounces by weight (non-metric terms). This is an important concept to remember when using sculpture materials.

If some material is listed as having a "specific gravity" of 1.1 for example, it means that one cup of that material (8 ounces of volume) will be 8.8 ounces in weight (1.1 X 8).

Measurement Systems:

In other cases, powders for example, how much a specific volume weighs depends on how tightly packed it is.

This is also called specific density, another phrase for specific gravity.

The ArtForm™ for example, can weigh anywhere from 3 oz. per cup when fluffed up loosely (low specific density) to 6 oz. or more per cup when tightly packed (high specific density). A margin for error of over 100% in measuring just one cup by its volume alone if density is ignored!

In our BODY PARTS™ kit instructions and examples we nevertheless use volume measurements which work just fine for small lifecast purposes. However, it is very important to fluff up the powders just before measuring by volume. If you don't do this, when an example calls for one cup (3 oz. fluffed up) you could be adding twice as much by mistake if tightly packed. This of course would radically alter the behavior and outcome of the project.

IMPORTANT RULE: Always fluff up the powders loosely before measuring by volume!

If you wish to measure by weight, which can be useful in larger projects and required for Precision Lifecasting refer to the conversions provided in the Advanced Methods section of this Library.

Chapter 2a: The Facts of Life(Casting):
Getting the words right. Timing is everything!

Working Time:

Working Time is the amount of time a liquid medium remains fluid or able to be manipulated. In a LifeCast™ kit it is the time from mixing the powder and water together until the time that mixture begins to turn solid.

When that begins to happens it will no longer flow around or into the shape your are attempting to duplicate, leaving gaps or poorly defined areas of detail in either the mold or the cast. Or, if mixing continues the fluid will turn solid and be broken up into solid pieces (lumpy oatmeal) which can't then make a single solid for a mold or cast.

Work Time = Blend Time + Position Time

The model or object must be completely in the fluid before the end of the Working Time. For example, if the Working Time is 3 minutes the actual Blend Time should be only about 2 minutes to allow enough Position Time for the model to get into the pose of your design.

Working Time:

The Working Times of the single part ArtForm™ mold compound and the ArtCast™ statuary cement which come in our BODY PARTS™ kits are controlled by only two factors:
• Ratio: the amount of water to powder.
• Temperature: the heat of the water and powder.
These are described in detail below.

Remember we are useing volume measurements.
• We always place the water volume first in the ratios shown here and on the other pages of the LifeCast™ Library. So a 1:1 ratio woulb be equal volumes of water and powder (one cup each for example). A 2:1 ratio would mean twice as much water as powder.
• Also remember that the powders must always be fluffed up before measuring by volume.

ArtForm™: Equal parts (1:1) mix quickly but also begin to turn solid fast and are more like a thick paste than a batter. A 2:1 ratio is typical for the BODY PARTS™ kits
ArtCast™:The exact opposite is true of the cement. A 1:2 ratio is typical for the BODY PARTS™ kits. More about this in Chapter 3.

The Two Factors of Working Time:

1. The temperature of the materials (both the water and the powder).
• Cold water and/or powder makes the medium react slower, giving you longer working time. This is important in larger projects.
• Warm water and/or powder makes the medium react faster, giving you a faster setting time(below) and shorter working Time. This is important when working with infants who only require small amounts.
• The ArtForm™ mold compound is far more sensitive to temperature than the ArtCast™ cement.

The Two Factors

2. The ratio of water to powder. That means how much water compared to how much powder is mixed together. Ratio is expressed like this:
• 1:1 which indicates and equal volume of water and powder. For example 1 cup of each.
• 2:1 means 2 parts water to 1 part powder. In English this would read; twice as much water as powder.
• 3:1 means 3 parts water to 1 part powder. In English this would read; thrice (or three times) as much water as powder.
• 1:2 means one part water to 2 parts powder. In English this woulld read; half as much water as powder. Get it?

Earthium™ Note:
Since this advanced medium is in 2 parts (A & B) it has one additional very important control factor, especially when doing Precision Lifecasting.

Earthium™ NOTE:
That is discussed in the Earthium™ instructions and the Advanced Methods section. In this book we cover only the basics as they apply to the materials in a BODY PARTS™ kit.

Setting Times:

Set Time is measured from the end of Work Time to the complete "hardening" of the medium being used.

ArtForm™ Set Time is the minimum time the model(s) or object being duplicated must remain in the mold before being released or removed. The medium may continue to get firmer for awhile after that so waiting a little longer is usually wise but, not always possible.

Cold materials at every ratio allow longer Work Time and also require longer Set Time.

Setting Times:

This summarizes the ArtForm™ Work & Set Times.

ArtCast™ Set Time is very different. First, all the ratios are reversed. You typically use more powder than water.

Another very important thing to understand when using ArtCast™is a simple fact of physics:
• the more energy you put into the system by energetic blending, the harder the final result will be (see graph).

If the ArtCast™ cement is not mixed very well the resulting sculpture will be weak, easy to break with lots of cast bubbles and poor detail. The more vigorously you mix the water and ArtCast™, the stronger your sculpture will become.

This is why our instructions urge you soak the ArtCast™ first (to completely wet it and allow bubbles to escape) and then actively blend it for the time allowed (to add energy to the system) before pouring.

This summarizes the ArtCast™ Work & Set Times.

Earthium(f/x)™ Note:
Work and set times are nearly infinite. The entire purpose of its 2-part engineering (Part A is the thickner, Part B is the catalyst) is to allow the lifecast artist almost total control over his or her materials.

Earthium(f/x)™ Note:
It can be made to set as quickly as 30 seconds or as slow as an hour with proportionate working times. That is discussed elsewhere. In this book we cover only the basics as they apply to the materials in a BODY PARTS™ kit.

PolyArt™ Note:
Our silicone LifeCast™ media are not for beginners. However, after you understand the basics they are also not very difficult.

PolyArt™ Note:
Please refer to the PolyArt™ Instructions and Advanced Methods section in this Library. In this book we cover only the basics as they apply to the materials in a BODY PARTS™ kit.

Chapter 2b: The Facts of Life(Casting):
The Matrix (Mother Mold)

The word matrix is defined as something within which something else grows or is contained. In lifecasting the Matrix is any semi-rigid container which holds the liquids until they turn solid.

The matrix also determines the amount of water and therefore, powder a particular project will need.

The package itself is the matrix for the ChildCast™ and LifeCast™ kits. You should not use other containers for a BODY PARTS™ kit unless it holds the same volume of water and you have some experience

Also, a good lifecasting matrix should have some "tooth" to it. It should not be completely smooth on the inside or the mold will be able to move around, distorting in the process.

One method of making a smooth container suitable for lifecasting is to firmly adhere hook & loop (ie; Velcro®) strips around the inside for the mold to grip on to.

If you have done a lifecast where the bottom areas, finger tips for example appear flattened then you have used a matrix which was too slippery. You can read more about this common problem in the "Slip & Slide" section of Advanced Methods.

"Mother Mold" is another term for the matrix but this term usually refers to a free form, rigid casing or wrapping (also called a "shell").

That shell covers and conforms to the shape of an interior, flexible "daughter" mold.

These are described in more detail in Advanced Methods.

The BODY PARTS™ Matrix:

Our new, larger ChildCast™ and LifeCast™ packages are designed to allow much greater freedom to explore positioning options than the earlier cylinder could. Changing from a can to a box has increased the area by over 30% and we have of course, increased the amount of ArtForm™ and ArtCast™ accordingly – without increasing the price!

The box does require some simple preparation to be used as a LifeCast™ matrix which is both waterproof and also prevents Slip & Slide by the mold.

Matrix:

This illustration shows the two basic steps of preparation needed to create a simple but, roomy and very versatile matrix for the amount of materials included. Hook & loop as described above may also be used.

The BODY PARTS™ instructions provide additional detail and options for these set-ups.

Chapter 2c: The Facts of Life(Casting):
Materials Preparation Techniques.

Blending Methods:

Mixing of the materials is very important in lifecasting. You are mixing a liquid (water) with an absorbant solid (powder) within a limited working time. Not mixed properly it will be lumpy, poorly dissolved and full of bubbles. The resulting mold will not be able to duplicate the fine details of the anatomy or object.

We have designed several unique, simple solutions which are included with each BODY PARTS™ kit. BlendBags™ are specially designed to make preparing up to 10-12 cups of LifeCast™ mediums easy. Specifically, they allow the artist . . .
. . . to have direct contact with the medium, to feel its behavior rather than working with insensitive tools and abstract rules.
. . . to minimize air bubbles by creating a practical vacuum chamber for the mixing process.

Blending Methods:

. . . to add large amounts of energy to the fluid system in a short period of time without electro-mechanical aids.
. . . to control the fluids in a neat, organized fashion, putting it where you want it.

BlendBags™ take a little practice and the following illustrations show the correct way to use them. I urge you to empty the powder from one and practice with just water to get the idea of wetting, burping, blending and pouring.

How to use a BlendBag™:

1. Measure the amount of water needed for your design. This will be equal to the volume of your lifecasting matrix minus the volume of the forms to be duplicated.

In a BODY PARTS™ kit the instructions give the step-by-step process since the volumes are based on the size kit you have. The water is then poured into the BlendBag™ with its premeasured ArtForm™ already inside.

BlendBag™:

This can also be done by displacement measurement when using other containers or techniques as described in the Advanced Methods section of this Library.
• A little experience will make this process familiar and easy to estimate materials.

2. Quickly hold the top of the bag closed and rotate the contents to moisten the powder so it doesn't blown back in your face.

Set the bag on a flat surface and 'burb' the bag as shown to eliminate as much air as possible. This not only minimizes bubbles but ensures you do not get a "balloon effect" which prevents mixing. Now slide your hand up to the bag top without letting more air back in. Grip the very top of the bag firmly with one hand.

This process creates a "vacuum chamber" for blending the water and powder without creating all the bubbles which cause so many problems in every molding and casting process.
• Again, a little practice will make this technique almost second nature to you.

3. Holding the BlendBag™ tightly closed about 1-2 inches from the top mash and blend the materials for the time allowed by your temperature & ratio or until smooth (see Work Time above).

In a BODY PARTS™ kit this will be 2.0 minutes using 65-70 degree (F) water. The ArtForm™ will become smooth and thickened in the bag. A few small lumps won't matter. The kit's practice exercise will show you what to expect.

Note: Many clean looking tap water sources are actually filled with significant amounts of metals such as calcium and magnesium or other contaminants. If you have problems with the practice exercise then use a bottled or distilled water.

4. The blended ArtForm™ should be like pancake batter. A few small lumps will not matter.

Quickly pour out the mixture into your lifecast matrix then squeeze out the remainder form the bag like a toothpaste tube. Making a 'nozzle' with your hand as shown lets you aim the fluid where you want it.

Proceed with the next steps of the project as described in the instructions or elsewhere on lifecast.net.

Note: If you are absolutely certain that both the water and the powder were withing the correct temperature and ratio guidelines and still get a lumpy mixture then your water source is probably contaminated.

Using Earthium™ adds other options to this process for additional creative freedom.

Other Blending Methods:

If you choose to mix the powders and water with more traditional tools then follow these suggestions:

1. Add the powder gradually to the water while mixing.
• The ArtForm™ will float on top and gradually thicken as you stir.
• The ArtCast™ will sink down quickly with lots of bubbles coming out, releasing the trapped air so you don't get as many cast bubbles.
2. If possible use a rounded bottom mixing container so no powder gets left out of the mixture by being trapped in the corners.

3. Use a wire whisk rather than a spatula or spoon to do the mixing. This breaks up the lumps best and if you keep it submerged in the liquid, moving it back and forth instead of up and down, there will be fewer bubbles mixed in.
• Scrape the sides of the container frequently while mixing to ensure a complete blend.

2-Part mediums like Earthium™ or PolyArt™ have considerations which are described in Advanced Methods.

You can also use what's called a "Jiffy®" mixer attached to a power drill for very large amounts. Most hardware stores would sell these typically for mixing paints.

This is "overkill" in the small amounts used in a BODY PARTS™ kit but, can be very useful for preparing the larger volumes needed for group or body lifecasting.

Go To Chapter 3: Go With The Flow:
The physics of fluid behavior in lifecasting.

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