CONSTRUCTION OF A CHEAP ZOMBIE HAND
This is how I make my zombie arms too.
The supplies are few and simple. Here's a list. I'll expand on the list below.
THE MAIN ARMATURE FRAME
Cut 5 long pieces of wire and space them from the base using your wrist and hand as a guide and tape them in place. Then using your own hand as a guide again, mark with a sharpie where to cut the finger tip lengths. Then snip them to the proper length. I snip them at a sharp angle (this will help later on when you have to impail the foam knuckle joints). I also put a smaller piece of wire across the base of the wrist and tape it in place to steady the finger wires. This makes a total of 6 pieces of wire.
Mark your knuckle location on the wires with a thick Sharpie using your own hand as a guide. And using your own thumb as a guide, bend the thumb joint into the proper angle. Bend/pose the fingers any way you want at this point. I'm keeping the fingers flat on this hand so that you can better see my results in the photos.
Cut 14 small cubes of foam to use as knuckle knots. Aim for about 1/4" cubes. Some cubes will be larger than others because you can't be exact. So plan out where you want your foam knots (or tape balls) to go by size (with the larger ones being at the base of the fingers and the smaller ones at the tips).
One at a time, impail the foam knuckle knots onto the armature and using small pieces of masking tape, wrap in place. This is where you kinda round off the cubic shape of the foam knots. Continue adding/taping all the knuckle knots with tape. This step holds the knuckle knots in place and prevents sliding during the next step.
Now we form the finger bones with tape. Take a long piece of tape and lay it lengthwise over a finger bone. Then bend/wrap it around the armature and knuckles.
Fingers and knuckle knots taped and in place...(note the thumb angles and bends).
Now we work on the wrist. Make 6 balls of masking tape and arrange as shown.
Then take a strip of masking tape and adhear them in place...
Now it's time to bring it to life (or ummm...death). Assemble your armature, cotton batting, latex floor/carpet adhesive, brush and wax paper together...
(At this point it would be wise to plan ahead and bend some wire into a hook for you to hang your hand on while the latex dries later and pick out a place to hang it. I use my diningroom chandelier.)
Coat the thumb and base of hand with latex and wrap the cotton batting around and upon it. It should look something like this:
Then brush over the cotton with more latex and pull and wrap it here and there. I find that you need a good load of latex on your brush or else the brush will just stick to the cotton and pull it badly. Load the brush thick and anchor the edge of the cotton with adhesive first, then lightly pull it across the cotton.
You can build up latex/cotton to add flesh where you want here and there dependent on the amount of decay appearance you wish.
Below is a top and bottom view of my hand. I will finish it off by sponging on some redwood or oak colored minwax stain.
And remember that the armature is made of wire so you can pose them any way and time you want!
Bottom of hand...
A big consideration is carpet/floor latex vs regular latex...regular latex is noxious...horrible stench and is uber expensive. Carpet/floor latex is much cheaper but dries slower. I used carpet latex. It dries to the touch with a day or so but stays tacky/sticky for weeks to months (Dependant on moisture conditions). Carpet latex requires a good safe place to store/hang but once it dries completely, it's good to go for years and looks just as good as the more expensive stinky latex.
If you brush it with talc, you don't have to worry about the tacky factor. I haven't tried that yet though but it sounds like it would work fine.