How to Handcast

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By John Greves
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Creating the Handcast in the original container

As fast as children seem to grow, you can freeze their little hands for all time, and can even hold their favorite object such as a marble or toy! For that perfect couple, read "Wedding Handcast"

Difficulty: Moderate

Instructions

Things You'll Need:

1 to 2 cups of lifecasting alginate.
Slightly warm water in a clean bowl.
a paper container tall enough to surround the hand up to the wrist without touching the sidewalls.
a kitchen whisk or mixer.
two to three pounds of plaster of paris.
a utility mixing container for the plaster
Old clothes, Extra water & paper towels
Graduated Measuring container(s)
A camera for sure!!!

Step 1

Practicing the Pose...

Have child roll up sleeve, grasp toy or marble if desired and lower hand till fingers touch the bottom of the empty casting container and then raise 1/2 inch or so as a practice drill - Decide on the hand pose the child or sitter would like to "Immortalize"
Step 2

Calculating the materials required...

Put the child's hand in the casting container and add water to desired casting level... This level of water is the amount of total casting fluid that will be needed to produce the cast.
Step 3

Pour off one third of the water from the casting container and then measure the remaining amount in a graduated mixing bowl - You will need one part alginate to two parts water (For example 1 cup alginate to 2 cups water)
Step 4

A great parent/child moment to remember!

Pour the two-thirds water into the mixing container and make sure that the child is all set to go! Pour the one third measured alginate powder onto the water and mix immediately by hand or power mixer for a minute or so until blended and bubbly. Child should dip his/her hand into extra water, shake off excess and get set to dip. Pour mix into casting container and assist child in lowering hand into container with slight wriggling motion until first finger touches bottom and then back up 1/2 inch... Remind child to assume planned pose and to avoid touching the sides of the container with fingers - You may have to help hold their hand in place until mix gels, you can tell by touching top of mix with finger until it feels like set Jell-O.
Step 5

Removing the hand and leaving the toy in the negative cast.

When set, have child start to wriggle fingers and pull hand out - If you used a toy or marble,have subject leave it behind in the alginate so that it will be embedded in the final sculpture. Removing the hand is a bit like pulling your foot from mud... be patient but firm and the air will suck in through the wrist and replace the vacuum without tearing the alginate.
Step 6

Negative hand ready for plaster...

If all went well, you now have the negative alginate handcast, ready for filling with plaster to immortalize for all time!!! Depending on the amount of water in the alginate, it will start to shrink relatively fast - You must now do one of two things, fill it with plaster or stabilize it by filling it with water and wrapping with damp rags... That will let you transport it back to the studio or postpone the positive casting. -To create the positive handcast, Read "How to plaster cast from an alginate mold"-