|
Captain
Total Posts: 160
Joined 2011-05-19
|
As
promised, I am going to show you one way I make molds. There are so
many different ways to make molds, but generally the principal remains
the same. Mostly it is the choice of materials that constantly changes
depending on what your master is fabricated from. Sometimes a master
mold will need to be flexible. Other times it needs to be rigid or semi
flexible.
When I first go to make a mold of an object, the first thing I have
to consider is the general plane orientation of the sculpted piece. For
example, if I have a humanoid with protruding limbs, I would divide
the piece into separate planes. Usually this means molding the body in
pieces; having a leg that is bent from the primary body plane cast
separate, or weapons, or arms…etc. Sometimes this means your figure
will be cast in as many as 4 - 5 pieces. Don’t worry about how many
pieces you need to cast, because multiple pieces does not really add any
time to the final casting production process; since everything is
usually cast in one shot using the same pour.
The next thing I have to consider is what my master is fabricated
from. Can the master be heated or does it have to remain cool to
prevent it from melting? Is the master soft or rigid? Will the master
dissolve in water or oils? As I said above, the principals of molding
remain the same, but the materials used to do it will change depending
on how you answer these questions. Sometimes I make molds that are
rigid on both sides and are made from the same material that is being
poured into them to make a cast! Many times I make molds that are rigid
on one side and flexible on the other. It all depends on how your
master is shaped, what it is made of, what you want your finished
product to be cast from…etc.
Don’t let cost scare you away from making molds at home! I’m going
to show you a way to make molds for around a couple bucks using
household items. Yes, the ‘ghetto’ way! You will be astounded when you
see that the detail produced from hand casts is far better than most of
the mass produced plastic gaming products.
So here we go (photo 1 shows what we will be making):
Not too long ago, I decided that I wanted to make a set of wands for a
figure. I wanted my masters to look as realistic as possible, so my
choice of materials is going to be natural objects. I went on a walk
and found some interesting sticks and picked up a couple of quartz
crystals off the ground (yes, where I live, there are places you can
just pick crystals off the ground…lol). I superglued the crystals to
the sticks. Next I wanted the wands to be able to swivel in the hand of
my LEGO figure so I found some appropriate sized beads and glued them
to the opposite end. Now I have my set of three wands; one plain one,
and two with crystals at the end (photo 2). It is time to mold them so I
can have multiple colors to choose from and play with. Yay!
I know that my masters can withstand heat, so this means I can make
my mold using material like Sculpey III and hot glue. I chose to use
Sculpey III because after it is baked, it has a minute flexible quality
that will help assist in removing the master. I chose to use hot glue
gun material for the top because it provides even more flexibility yet
still retains its rigid casting shape. Because one will melt easily
with heat, and the other will not, I have to make the mold so that the
hot glue side is fabricated last.
First I coated my masters in vegetable oil so they would release from
the mold easily (photo 3). Too much oil will lessen detail or dissolve
the material (depending on what material you are using) so I use
caution here. I flattened a piece of Sculpey to about 1/8 inch thick
(photo 4), then I gently pressed the masters into the clay to their
midpoint (photo 5). This midpoint is going to be the planned seam for
the mold. Next I have to compress and push the clay against the masters
because when I pressed them in, it created a tiny rounded curve that
did not terminate sharply where the seam line is going to be (photo 6).
I do this with a toothpic that has been shaped like a flat
screwdriver. When I do this, it leaves lots of tool marks in the clay.
For easier mold cleanup, I smooth out all these tool marks with the
rounded end of a paint brush (photo 7). I then need to make sure that
there are some alignment points on the mold so that when the two sides
are put together they mate perfectly without an offset seam. I make
those points by simply pressing the rounded end of a paintbrush into the
clay in 3 places (photo 8).
(In my next post I will continue.)
Image Attachments
|
You make it look simple..I´m really bad at making molds 
No comments:
Post a Comment