Alright, i have the larger mold down.
First, we have the subject, the Lindberg Skull. I personally wanted a toothless skull model, but the steps are the same.
First step is preparing the model. The Linberg skull has hollow eyes and nose cavities, and the areas right behing the eye sockets where the lower jaw connects. A couple small holes here or there on the underside, and in some of the tooth cavities.
First, we fill all these with clay. I'm using Crayola Model Magic, but have used play doh and silly putty before, along with more proper clays as well.
(will be 2 pictures here as well, but they're on another camera right now.
Now, when applying the latex, most faqs have you just lay this thing flat and paint on from the top. This leaves a large portion of the underside never modeled, and thus never replicated. I personally wanted more detail, and we are first applying latex to the underside. Turn the skull upside down, and you can see just how much of an undercut we are making. Steps are the same as above, except we are brushing on the latex instead of dunking due to size. Let dry, go again, pop bubbles in beteween.
(this is 3 coats of latex on the bottom)
Now, simply flip over and do the same for the top half of the skull. Making sure to get in the eye and nose sockets as well. You can see we made a little handle area at the base of the upper jaw. I actually punch a hole in this area and hang the things when I am making plaster skulls.
Now, as this is a larger skull, we need to reinforce the mold to help it hold it's shape under the weight of the plaster we will be adding. We can add this reinforcement anywhere it does not need to stretch, so everywhere along the face, top, and down the sides and back untill they hit the widest portions. Do not add any past where it begins narrowing again, or you'll never get these molds off.
We'll be adding cheese cloth as reinforcements. Measure and cut the strips you'll need. Brush on a thin layer of latex.
Now add on the cheese cloth.
Then cover that again with a nice thick layer of latex.
Repeat for any areas you want to reinforce.
Here we have the top coated, and the first eye socketgetting it's cheesecloth.
