Movie makeup unmasked

A makeup artist who now works with chemists shares Hollywood's secrets of making facial molds. Rob Krebs now works for the American Plastics Council and is the proud owner of the sculpted nose that Jack Nicholson wore in the film Chinatown. Inside Science News Service spoke with Krebs to find out how the experts make the scariest masks and faces.
ISNS: What major known ingredients that are typically mixed in to make the "skins" like those used in previous films?
RK: Well this is a funny one, because most of the formulas are proprietary. Dick Smith was the first union makeup artist with a card to operate on both coasts of America. Hollywood dynasties of families ruled the makeup world so the formulas of the Bau family, and others became secrets to help the family earn money. Dick was the first to share this info freely.
I understand that some of the effects and make-up artists used some pretty potent surfactants, but nonetheless, everyday household substances- like ammonia & chemicals that even the average, non-chemist, non- engineer-type person would be familiar with. tell me about this, and what a product like ammonia, for example, might do for the type of "skin" or "appliance" being fashioned in the earlier days of make-up effects, like those seen in movies going back, 10, 20, and even 30 years ago.
[Dick] also invented the gunshot to the head. He puts morticians' wax over red 'blood' around a shirt button buried in the morticians' wax and tied to invisible fishing line. When the shot is fired, he pulls the string and you see a hole in the forehead!
ISNS: Are there any household substances, such as ammonia or other chemicals used and what do they do for the "skin"?
RK: As I understood this at the time the ammonia was a chemical agent that kept the parts of the latex molecules from sticking together sort of a' separator' but when the gelling agent for the foam was added [after the foaming - literally in a Kitchen Aid Mix Master whipper] it neutralized the ammonia and allowed the latex to coagulate, but it was in a foamed state at that time. The foam is poured into a negative mold and the 'skin' comes from the accumulation of foam against the surface of the mold, like the skin of a cheese that melts against a baking pan in an oven.
The latex foam ingredients were experimented with and experimented with until they got foam that basically wrinkles like skin, folds like skin and allows the actor to move his face as naturally as possible, and took makeup but did not dissolve under the lights. When they had the right 'formula' that was a family secret. Some formulas absorb light so differently that you could tell where the appliance ended and where the actor's skin began -and it looked fake. Others were more natural and those people were successful.
How do these 'skins' and 'paints' used on actors then, compare to material used in everyday consumer products such as materials found in automobiles (car seats), household furniture, like bedding, mattresses, clothing, or the kind of stuffing inside pillows?
RK: technically very similar however the foams for cushions and other items in cars, for example, are much, much more durable, lasting ten to twelve years of daily use, acting foams last about eight hours of filming and are not re used.
Are there certain safety issues that apply in both making the rubber/foam/latex molds?
RK: I'm sure there are but as these things were developed I'm sure they did not know if any of these chemicals harmed actors or the creators at first. Remember the story of the Wizard of Oz: the first tin man was Buddy Ebsen. (They used) aluminum dust. He breathed it and nearly expired. Not only did he nearly die he lost the part and the studio gave it to Ray Bolger! Then they used aluminum paste. There were originally [safety issues & potential hazards], not so much any more. Lots more is known about what chemicals can be harmful and which can be used to the same effect but are more recent discoveries.
For bald caps, very powerful solvents meant to dissolve the plastic film and melt it invisibly into the skin are used. [This] may cause harm if you are over exposed.
Was this stuff difficult to work with?
RK: Oh absolutely, this is science in its roughest form: experimenting over and over and over to get the foam to set after its in the mold, not before, to get the right consistency to be realistic, to not bake it too long in the oven to 'cure' it, to make the edges come out just right so they can blend seamlessly into areas of the face, finding 'release' agents to coat the molds so that the cooked latex comes out without tearing, or release agents. For casting the sculpted appliance once it's created so that the mold comes off clean and ready to fill with foamed latex.