The technique of the aluminum soft plastic lure molds allows creating molds that reproduce the complete model in all its parts, in the round. Otherwise, it is impossible to extract from simple single-valve molds.
In the construction of a mold, the original model to reproduce (master) can be an already existing figure, or a personal creation of the model maker. To make a model, various materials can be common, such as:
Plasticine is undoubtedly the most suitable material for aluminum soft plastic lure molds. It offers the greatest creative freedom and allows you to create the desired shape in a short time.
Non-porous surfaces (e.g. metal, plastic) do not require the preliminary use of release agents. On porous ones (wood, concrete, plaster, clay, etc.)
It is in order to prevent the silicone rubber, fluid before hardening, from penetrating into the pores making subsequent demolding operations more difficult.
Moreover, it is very important that the separators are very fluid. They are applied (by spray or brush) in a very thin layer. It is to interfere with the precision of the details to aluminum plastic lure molds.
Once the volatile part contained in the separator has evaporated. It is advisable to subsequently apply a very thin layer of waxy release agent.
Once you have the original model to reproduce, the first thing to do is to get a pourable silicone rubber for molds. This rubber consists of two parts, a silicone compound plus a catalyst. You also need plasticine and wooden tablets of various sizes.
On a wooden base, aided by plasticine, form a kind of box of such size as to comfortably contain the model to reproduce. In our example we will proceed to the reproduction of a lead soldier. Make sure that the sides of the wooden boards fit together perfectly and leave no space.
We will fill this structure with other plasticine until we reach half the height of the box and then we will insert, by pressing lightly but firmly, our master. It must insert into the plasticine up to about half of its height.
If it is our intention to use a polyaddition silicone rubber for the production of the bivalve cast. It will be necessary to use plasticine without sulfur. This does not create phenomena of catalysis inhibition.
Alternatively, always place the aluminum soft plastic lure molds in the same box and pour some melted wax to cover the lower half. In this case it is advisable to wrap the lower part of the model with aluminum foil to prevent the wax from adhering.
With this system the division of the mold is in a straight line. With the plasticine method a more complex division plane is easy to obtain. It is able to exactly follow the morphology of the object to be reproduced.
Adjust the surface of the plasticine or wax around the aluminum soft plastic lure molds and form four hollows on the four sides of the modeling clay. This will be common to align the two halves of the mold.
At this point we will have to decide whether to proceed with the preparation of the sprue and the air escape routes at this stage, or whether to wait until the realization of the two silicone rubber molds finishes.
In the first case, to create the casting duct, through which the material will pours into the mold, a sort of plasticine funnel prepares and two equal parts divides. A half funnel attaches to the plasticine. This divides surface, with the thinnest part connected to the aluminum soft plastic lure molds at a predetermined point and the flaring outwards.
This adheres to the edge of the containment box. The other half of the funnel will then be common to complete the conduit in the second valve.
It is also necessary to prepare a vent channel for the air near the pouring one. For this purpose, you can use a drink straw half-drowned in plasticine. This connects the model to the edge of the wooden box. Any additional vent channels require at all aluminum soft plastic lure molds highlights to prevent air pockets from forming when the material pours into the mold.
It is a basic example of what we will have to do as we should adapt the work to each subject taking into account. It is to ensure that the material with which to fill the mold arrives in each corner before solidify. The air escape channels must be sufficient in order not to allow air bubbles to remain in the recesses that the lead will have to fill.
At this point the model is ready for the construction of the first valve of the mold, but first we will have to proceed with the preparation of the silicone rubber
Before talking about their preparation, let's see what silicone rubbers are.
What they are Silicone rubbers are liquid or paste products that are cold vulcanized by means of a catalyst, from which stable compounds with high elasticity are obtained.
Thanks to their peculiar characteristics, silicone rubbers offer great advantages in the construction of aluminum soft plastic lure molds. It is good in the artistic sector, objects, restoration and scenography where, in some cases, they prove to be truly irreplaceable.
One of the fundamental properties of silicone rubbers is the excellent non-stick effect towards the materials they come into contact with. This means that they do not adhere to the model.
Therefore, no release treatment is important, both on the model and in the mold. Furthermore, silicone rubbers have excellent reproduction fidelity down to the smallest detail, and good dimensional stability. Their elasticity and tear resistance allow you to easily demold.
With silicone rubber you can make casts of an infinite number of objects: statues, figures, bas-reliefs, architectural elements, rocks, fossils, tree trunks, etc.
You can also get casts on still wet clay. The rubber comes off easily and does not release greasy substances or residues that could damage the model.
The aluminum soft plastic lure molds can be common for reproductions with different materials, such as polyester resins, rigid or expanded polyurethane, plaster, marble, wax, cement, etc.