Page 2

Christian Hanson

picture 5

picture 6
Step 4) Plaster Bandage Application:  Once the alginate has set up, plaster bandages need to be applied. Take each four-layered strip and dunk it into the bucket of warm water. [picture 5] Squeegee the excess water with your fingers, and apply it to the alginate. [picture6] Overlap the bandages until all of the alginate is covered. Leave a small amount of alginate around the edges of the mold exposed. In this instance, I went so close to the edge with the bandage, which made removal difficult. Take the small strip of bandage and place that between the nostrils, and make sure to keep the nostril wholes open, so that your subject can breath well. The bandages set up in just a few minutes. [picture 7] You can tell when the bandage shell is set up once your fingernail will no longer leave an impression.

picture 7

picture 8
Step 5) Mold Removal:  To remove the alginate and plaster bandage mold, have your subject lean forward holding the mold with his hands. Have him move his face around to loosen the alginate from it. Be careful that the plaster bandage shell does not separate from the alginate. Carefully assist the removal by putting your fingers between the alginate and his face and loosening up the edges. [picture 8] Be patient, you do not want the alginate to rip. Once the mold is removed, your subject can go off and clean up. You, on the other hand, still have more work to do.

The nostril holes that were so carefully kept open will now need to be covered. Mix a small amount of alginate and slowly push it into the mold from the outside, being careful not to get it on the inside of the mold. When it sets, cover the area with a fresh strip of plaster bandage.

The alginate will start to shrink as it is exposed to the air. If you cannot start the plaster cast immediately, place a damp paper towel inside the mold to prevent this until you can start the casting.

picture 9

picture 10

Step 6) Plaster Casting:  This face-cast is going to be used as the base for a sculpture which will become a custom, slip latex prosthetic. If I was fabricating a foam rubber appliance, Ultracal 30 cement would be used for the cast, but in this case Hydrocal plaster will work. Hydrocal can be mixed fairly easily. First, fill your mixing bowl with approximately three cups of water. I just went by eye here, as I have years of experience mixing plaster. You will need just enough to give the mold about a half-inch layer of plaster. Sift in the Hydrocal until the top of the mix looks like a dry lakebed. [picture 9] Mix this up thoroughly with your hand, making sure to prevent too many air bubbles from building up. If you have sensitive hands, you may want to use latex or vinyl gloves. Once the clumps are out, use the disposable brush to paint in the plaster. [picture 10]

The aim here is to get the plaster into all of the details of the mold. Build up about a half-inch of plaster and allow it to set up. This should take only 20 minutes or so. It is a standard in mold making and casting to create a layer of plaster-soaked burlap in case the cast cracks. The burlap will keep it from falling to pieces. Cut the burlap into squares approximately 4" X 4". [picture 11] Mix up another batch of plaster as before and dip the individual burlap squares into it. Cover the inside of the cast with overlapping plaster soaked burlap. Use the remaining plaster to achieve a total even thickness of about 1/2-inch. As the Hydrocal sets up, smooth out the back of the cast. Once this final layer is completely set up, you can turn it over and remove the plaster bandage from the alginate mold. Finally, carefully peal the alginate from the Hydrocal cast, and there you have it. And exact casting of your subject's face. [picture 12] There are usually minor imperfections due to air bubbles in the alginate, which can easily be removed with a woodcarving tool.

picture 11

picture 12
If your first attempt at life-casting does not work out, do not give up. Most everyone who has done multiple life-casts has some story of things going badly. I am certainly no exception. Once, doing a full head cast, all was going well until we poured the plaster into the mold. The bucket that it was sitting in slowly filled up with the plaster. We were babbled until I realized that I had forgotten to plug the nostril holes before pouring the plaster! Another time I wasnít sure how many layers of plaster bandage were needed to keep the alginate in the shape of the subject. Using only two layers, the cast came out as a bizarre, distorted version of the subject. But, as they say, thatís how one learns. Read up more on life-casting, get your materials ready, convince someone to be your subject and youíll be a master caster in no time. Next issue: fabricating a basic latex appliance.

Return to Page 1 Return to The Articles

The Effects Lab
©2006 Joe Lester
©2016 John Lester