Model kits are a popular hobby. Many people enjoy the experience of putting together a model kit and how much satisfaction they get when it is finished. But how exactly do you make a model kit? This blog post will look at how the process starts with making small plastic parts in large numbers.
History of the First Scale Model
Model kits have been around since at least 1850 when French railway engineer Lionel Jospin patented his design for an electric train in 1884–1885. Starting about 1840, he had experimented with clockwork trains before turning his attention to electricity as a motive power. In 1891, Uwe Tellkampff invented the first model car, which he named “Spielzeugauto” (toy car) and patented in 1898. The kit was powered by clockwork. By the early 1900s, kits were being offered for motorized models, but they were slow to take off because of the expense involved in producing them at that time.
Raw Materials Used in the Manufacturing of Model Kits
A short overview of the materials used in model kits is as follows:
The materials used in the manufacturing of model kits consist of diecast, injection molding, and other materials.
Diecasting is a process where lead and zinc are put together in the mold, leading to adopting a particular shape. To make a plastic model, you need to melt metal and pour it into a mold. Then the metal will harden.
Models manufactured with diecasting consist of different materials, including metal, plastic, glass, etc., one perfect combination of these materials makes it sturdy for this type of model. Besides this process, injection molding is also used to make specific models made from various combinations like zink alloy or plastics. The most important thing about dies casting is that it uses different raw materials, lead or zinc alloy. Zinc can also be mixed with small quantities of aluminum and copper etc.
Polystyrene Plastic is a ubiquitous material that is used in the production of models. It was first introduced to model kits in the 1900s. It is durable and versatile. It is also low cost. Polystyrene plastic can be molded into any shape with ease under controlled conditions of pressure and temperature. This feature makes it an excellent choice for making models.
Polystyrene plastic is used in model kit production because it can be turned into whatever color desired by adding paint or dye before molding (most other plastics are produced in their original colors). This type of plastic among model manufacturers continues to grow as more people enjoy collecting these miniature replicas from various franchises, such as movies, video games, and TV shows.
Photo-Etched Metal Parts
Please don’t be intimidated by the term “photo-etching.” It doesn’t mean anything more than using a photographic technique to create ultra-delicate metal parts for model kits, and it’s actually quite simple.
Photo-etched metal parts are made by combining two common materials: photo plates and etched metals. A photographic plate is created with CAD drawings which can then be exposed to light to produce the desired shape of the PE part. Pictures are put on the metal. They are called photo plates. The images were exposed to light to make them visible on the metal. But if you want your model kit looking extra elegant and realistic, photo-etched metal parts are precisely what you need!
Cast Polyurethane Resin
Polyurethane resin is a material used in the construction of model kits. It’s often mixed with other materials to make sure that it can be sustainable for continuous usage. Polyurethane resins are viable materials added to the models for making the best parts of different models, but they have drawbacks too.
It’s cheaper and easier to produce than injection molding. Still, it has a downside; too-parts manufactured with polyurethane resins are not durable compared to plastics or alloys because these parts wear out quickly.
Metal Cabled and Tank Tracks
It’s also important to understand that many military models have metal cables for towing other vehicles. They can’t be replaced with plastic strands because of durability problems, so some leading companies provide them with their model kits while in the other you have to buy them from the market.
Earlier I wrote an article about tank tracks: What are tank tracks and how to draw them?
If you have a tank track, you may get away from it to run most efficiently. These tracks are mainly manufactured with rubber-like materials, and the injection molding method is used as well.
Model Kit Design
A new design model kit takes 1 year and costs around $250,000. When you want to make a model of an old car, first take hundreds of pictures. Then you will need to take photos from all angles so that the designer can reproduce them on their computer.
When companies design a new model kit, they give model makers computer information about the parts. The model maker uses computers and software to make a scale design. They then use this information to create drawings that can be used to make molds for the model kit. This process can take several hundred hours of engineering time.
The Design Moves to the Pattern-Making Phase
Skilled artists follow the designer’s drawings and carve out a model from balsa or other softwood. It is made at two to three times larger than the scale of the model kit to add more details to it. This also shows how accurate the design is and provides a basis for all the molds made for model kits. As they carve, they fit them together.
To make a wooden pattern, the maker will coat each part with a hardening plastic. The maker will remove the piece from this coating and form it in a mold. Making these molds can take over 1,000 hours.
Engineers Use Design Drawings to Make a Tool
The tool is the metal cast of the plastic parts that are molded on a single form. This usually happens in rectangular shapes that will fit into boxes. Several standard box sizes are used, with the end of each branch narrowing into nodes for assembling models. Design engineers also use CAD to map out their tool layout.
The Resin Molds are Tools Used to Make the Tools for the Model
They are created using a pantograph to copy the shape of each model part and make it smaller. The pantograph has two parts: one needle-like part is run over the surface of the mold while another, a cutting blade carves steel at a smaller scale. When this tool is finished, it is polished, and more details are added with handwork. Some of these details can’t be seen by human eyes without a magnifying glass.
Other People Work on the Paper Aspects of the Model Kit
These designers take apart the plastic models and put them back together to become instructions for someone to follow. When they are reassembling it, they write down what needs to be done while they are doing it. They also draw pictures while they go along. Other artists design things that go onto the model like decals, which could be copied from accurate decals on a car or have different formats like racing stripes. Sometimes more research is needed to capture these details with accuracy.
The Box Cover
It helps the builder see what colors are on the model. The pictures may be photographs of the actual model or an artist’s impression. For example, a Fokker triplane box cover might picture the Red Baron’s airplane in a dogfight. Elsewhere on the box cover, there are descriptions about what you get when you buy it, how hard it is to build, and other details about it.
Quality control is an essential and crucial aspect of the entire process. Designers supervise the whole process and make sure that nothing is overlooked, and for this reason, designers should be well-versed in the subject area they are designing. The design should be approved by a review board before proceeding to the next phase. The quality control personnel also oversee the injection molding and dipping processes and assembly line progression. Every kit requires quality control inspection to ensure that all parts are present and accounted for.
Byproducts and Waste
There are a lot of good things that come out of the manufacturing process. But there are also some not-so-great byproducts and waste products. However, model manufacturers can recycle much of the waste associated with manufacturing plastic models. Plastic waste can be melted and remixed in future batches. Steel from tool making is collected and sent to a metal recycler. Paper products are made from recycled paper.
Safety is an essential concern for employees of the model kit factory. Employees must wear gloves, glasses, and protective gear when operating machinery or working with chemicals. The area where resin molds are made is equipped with ventilation hoods to protect against harmful fumes. Operators of the injection-molding machines must also wear heavy gloves to protect themselves from heat generated by these machines. These safety precautions are necessary because some chemicals can be dangerous if not handled correctly or breathed in too close proximity over a long period. All employees who work on-site at this factory receive extensive training on handling hazardous materials correctly and safely so as not to endanger themselves or others around them.
In the future, model kits might play a role in other areas of education. As technology improves and becomes more affordable, it will be possible to use 3D printers for making models. This will allow students to create their own customized models with different colors and textures. The only limit would be their imagination!
FAQ about How a Model Kits is Made
How are model sprues made?
Some model kits are molded in halves, while others are done in multi-part molds. This is determined by how many pieces need to be made and how they will break if they were modeled individually. For example, smaller or thinner pieces may not hold up well when separated from their siblings. Instead, multiple light components will be grouped together, which can be pulled apart after curing within the final model kit’s plastic shell. If a part needs to stand out more, it can also be molded separately, but this adds another step onto production because now, at least two separate molds must be created for each individual component!
What are model cars made of?
Model cars are made out of plastic. Models may also include metal pieces and other materials like glass or wood, depending on the type of model kit assembled. Some parts in model kits will need to be painted, while others remain unpainted when they arrive at consumers’ homes.
What are some of the scale sizes for model cars?
- 1:43 scale is a model that is 3 to 5 inches
- 1:24 scale is a model that is 5-8 inches
- 1:18 scale is a model that is 8 to 11 inches
- 1:12 scale is a model that is 14 to 16 inches
What is model glue made of?
Model glue is made out of water, acrylic resins, and other chemical compounds.