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Plastic Kits & Plastic Modelling
These techniques are of equal value for scratchbuilding and kit construction, and are recommended for the use of adult scale modellers only.
This section includes:
Introduction | Tools | Adhesives | Techniques - Hints & Tips |
Introduction
It should be noted that all adhesives and fillers used in plastic modelling may be harmful if inhaled or ingested. Always use in a well ventilated room and never inhale the adhesive vapour. Replace the lid/cap when not in use. Super glues bond skin instantly! Wash well any spills in contact with the skin. Always follow the COSH directions on the bottle/packet.
Plastics are now one of the most popular model making materials. In terms of model kits plastic is now used more frequently than older materials such as wood and cardboard. It should be remembered that plastics are manufactured to differnt formulas depending on their potential use. Some plastics are much harder than others and are generally manufactured for industrial use. This section is based upon the use of styrene, a softer plastic used in model kits and in modelling materials eg plastic sheet for scratchbuilding.
Tools.
Only simple inexpensive tools are required for model making and kit construction in plastic. These tools can be purchased from our Tools and Materials Internet Web Shop. See the Shopping Index on the right side of this page or CLICK HERE
Knife - The best modelling knives are surgical scalpels.
They are extremely strong and can be purchased in a variety of styles with
various blade types. X-Acto and other specific modelling knives are
popular together with the basic but effective Swann Morton Craft Tool.
The most important fact is that the knife is comfortable to use and strong.
Remember to always wear safety glasses when using sharp instruments,
and to cut away from you. All craft and surgical knives are extremely
sharp!
Straight Edge - A simple but essential tool to ensure clean straight lines are
cut in a controlled manner. When using any form of model/craft knife, always use a steel
straight edge to prevent the blade cutting into the straight edge. A variety of sizes are
useful from 15cm to 100cm depending on the work. Safety straight edges are an advantage
as the 'holding' fingers are protected from the blade.
Cutting Mat - A recent innovation available in a varity of sizes from A5 to A3, the
'self healing' surface provides a good flat surface for cutting without damage to the blade.
Generally a good addition to any tool box.
Scissors - Good quality straight and curve blade scissors are often overlooked by
model makers but they can save time when cutting irregular shapes in thin sheet material. For accurate intricate work
use scissors with a small blade and long handles eg surgical scissors, available in a variety
of types. A pair of quality long blade straight scissors allows for neater straight cuts if a
knife cannot be used.
Retaining Tools - Basically anything that holds the items in place whilst the adhesive sets. Useful items include elastic bands, bulldog clips etc. Masking tape
or similar can be useful to hold the model while it sets or as a temporary fix when checking.
Plastic Shears/Side Cutters - When cutting parts from plastic kit sprues,
plastic shears perform a useful task by cutting the sprue without the danger of cutting
into the part. They can also be used to snip thin strip styrene.
Sanding Products - Plastics sand easily and a variety of sanding products help to
improve the finish on models. Standard wet and dry papers are useful together with sanding sticks
(used to file finger nails) which are abrasive boards similar to 'lolly' sticks. The Flexi-File is an essential requirement
when constructing plastic kits with circular/oval structures eg aircraft fuselage. This special
file wraps around the shape reducing the potential to file a flat spot.
Model Filler - It is virtually impossible to assemble a plastic structure without
having a joint visible to the human eye. Fillers should be used to produce a neat join prior
to painting. Commercial model fillers include Humbrol 'Model Filler' and 'Model Lite'. For
harder finishes Milliput is useful.
Drills - These include pin vice and small modellers electric drill (Expo or Minicraft) together
with an assortment of drill tools.
Adhesives.
It should be noted that all adhesives and fillers used in plastic modelling may be harmful if inhaled or ingested. Always use in a well ventilated room and never inhale the adhesive vapour. Replace the lid/cap when not in use. Super glues bond skin instantly! Wash well any spills in contact with the skin. Always follow the COSH directions on the bottle/packet.
Initially it should be stated that plastic is a complex family of materials which include polystyrene (not the white packing material but the standard material used in plastic sheet and moulds), ABS, Perspex, Lucite, Plexiglass etc. The adhesives listed below are for use with polyyrene, however plastic weld will stick the majority of those previously listed. Plastic adhesives are available as follows:
Tube Adhesive - Dispensed through a nozel similar to a small tube of toothpaste. Tube adhesives are often the choice of the beginner as they are included in starter kits, and are sold in most shops. Tube adhesives are comparatively expensive, and very soon become second best to liquid adhesives as tubes are more difficult to control and produce a 'string' which can spoil models. Tube ashesive is however useful as it is a thicker consistency and can be used to strenghten joints.
Liquid Adhesive - By far the most popular group of adhesives available in a variety of formats and applicators. Commercial liquid adhesives are available from companies such as Humbrol and Revell in small bottles with a brush attached to the inside of the lid allowing easy and accurate application of a controlled amount of adhesive. The same manufacturers extend the accuracy of the adhesive application by producing adhesives applied from a bottle with a needle applicator. Most experienced modellers purchase liquid adhesives in greater volume from several manufacturers according to their requirements, applying the adhesive with a small paint brush. The most popular liquid adhesives are based around various concentrations of MEK (Methyl Ethyl Ketone), however with some plastics a stronger bond can be made using Plastic Weld, probably the best liquid adhesive available.
Super Glue - Useful in most modelling situations super glue can be used on some harder to glue plastics; and on softer plastics where a rapid bond is required, or to join plastics to other materials.
Techniques - Hints & Tips.
This section hopes to give modellers a few basic tips to aid in the construction of plastic models both kits and scratchbuilt. Some hints and tips occur in the tools section above.
Where possible paint parts of plastic kits before removing them from the sprue.
When cutting parts from a sprue use side cutters rather than a knife where possible. Once removed sand the injection 'pip' until it blends into the model.
If a craft knife or side cutters are used to remove a sprue or projection, do not cut adjacent to the part as damage may be caused. If the injection pip is removed by a knife be careful not to cut into the part required. Sanding is usually more succesful.
Use a craft knife with the blade perpendicular to the subject to scrape edges preventing damage to the model.
When cutting plastic sheet or strips if the plastic is too thick to cut in one stroke, score the surface deeply and then fold at the line to break.
A useful filler can be made using super glue and baking soda. CAUTION IS NEEDED!
Small windows can be made using clear drying high quality PVA adhesive. Simply place the PVA into the window frame allowing a thin film to cover the window. This will dry clear like glass.
Effects and textures can be made on plastic sheet by scoring the surface with a craft knife blade.
Use liquid adhesives for neat joints. Tube adhesives should only be used to reinforce joints. Beware of the glue string from tube adhesives.
When using super glue never apply the glue direct to the part. Always place the glue onto a waste piece and apply with a small tool to avoid excessive amounts covering the kit.
Keep the knife blade vertical when cutting plastic card to produce neat joints.
When building box structures from plastic card, always make a ventilation hole to allow the adhesive gas to escape. Failure to do so may result in distortion to the model.