Plastics
Plastic has been used whenever possible in model making because it is often easier and faster to work with than wood, metal, or cardboard. Plastic can be sawn, blade cut, drilled, lathe-turned, carved, sanded, and filled. Most standard woodworking tools may be used on plastic, and it won't splinter. Plastic parts often join in seconds with small amounts of liquid solvent cement. For bonding plastic materials to foam, wood, or masonite, contact cement can be used. For large stock, many professionals prefer to use countersunk screws for attachment. A spray adhesive is sometimes easier for small jobs.
Plastics offer an incredibly diverse range of properties from extreme rigidity and clarity to flexibility and high impact resistance. Their versatility allows for the creation of intricate details, durable structures, transparent elements, and specific functional parts that are crucial for a wide array of models.
---Quick Reference: Plastics
Use this quick guide to understand the primary characteristics and common uses of different plastic types in model making.
| Plastic Type | Key Characteristics | Common Model Making Uses |
|---|---|---|
| General Purpose & Styrene Plastics | ||
| Styrene (Polystyrene) | Rigid, smooth, easily cut & glued, good for fine detail, can be brittle, warps with some solvents. | Scratch-building plastic models, architectural models, custom parts, vacuum forming. |
| HIPS (High Impact Polystyrene) | More durable & impact-resistant than styrene, less brittle, good for vacuum forming. | Durable model parts, RC body shells, prototyping, vacuum forming. |
| Butyrate | Pliable, machinable, durable, easily cemented, good for turning tubing. | Tubing, profiles, turned parts, durable pliable components. |
| Clear & Transparent Plastics | ||
| Acrylic (Perspex) | Crystal clear, glossy, rigid, excellent optical clarity, can be brittle. | Model windows, display cases, clear bases, lenses, architectural models. |
| Clear PETG (Copolyester) | Transparent, outstanding toughness & impact resistance, easy to thermoform, less brittle than acrylic. | Windows, protective covers, custom enclosures requiring high impact strength. |
| Styrolux | Transparent, high impact strength, crystal clarity, rigid, styrene-based. | Clear components requiring toughness (e.g., windows that might face impact), clear structural elements. |
| Clear PVC | Rigid, transparent (often slight blue tint), good strength & chemical resistance. | Windows, transparent structural elements, protective barriers where chemical resistance is needed. |
| Acetate | Flexible, clear film/thin, easily cut & bent, can yellow over time. | Small windows, overlays, stencils, miniature glazing where flexibility is needed. |
| High-Performance & Flexible Plastics | ||
| ABS | Tough, rigid, high impact resistance, good workability & bonding, strong chemical resistance. | Durable model parts, structural components, RC car bodies, functional prototypes. |
| Polypropylene (PP) | Flexible, semi-rigid, excellent chemical & fatigue resistance, lightweight, challenging to glue/paint. | Flexible parts, living hinges, chemical-resistant components, parts needing repeated flexing. |
General Purpose & Styrene Plastics
These rigid plastics are widely used in model making for their excellent workability, consistency, and ability to hold fine detail. They are easily cut, formed, and glued, making them ideal for scratch-building and fabrication.
Styrene (Polystyrene)
Styrene, or Polystyrene (PS), is a rigid, general-purpose thermoplastic. It's the most commonly used plastic in moulded plastic kits (such as Model Railroad, Automobile, Aeroplane, and Ship kits). For that reason, it has been chosen as the medium for many FineLine Structural model parts for compatibility in kit-bashing.
Characteristics:- Material: Polystyrene (PS) thermoplastic.
- Texture & Consistency: Smooth, hard, and rigid, available in various finishes (e.g., matte, glossy).
- Workability: Very easy to cut using the ‘scribe and break’ method, with a blade, saw, or laser cutter. It can be drilled, lathe-turned, carved, sanded, and filled. It bonds rapidly and permanently with liquid solvent cement. Reinforcement bracing is recommended when cementing flat sections for walls to minimise warping.
- Finish: Accepts most paints, including enamel, alkyd oil, latex, or acrylic paints specifically formulated for Styrene plastics.
- Resistance: Tends to be brittle, especially after lengthy U.V. exposure or painting. It is easily warped by solvents, so care must be taken when cementing flat sections. When constructing closed tanks or structures, venting is recommended to allow inside and outside temperatures to equalise.
- Fundamental for scratch-building plastic models, architectural models, and creating custom parts, particularly where compatibility with existing plastic kits is desired.
- It has excellent forming characteristics, ideal for vacuum forming intricate components.
- Widely available in various thicknesses, colours (white is common), and forms.
HIPS (High Impact Polystyrene)
HIPS (High Impact Polystyrene) is a modified version of polystyrene, engineered to be significantly tougher and more impact-resistant than standard styrene, while retaining many of its desirable workability features.
Characteristics:- Material: High Impact Polystyrene (HIPS) thermoplastic.
- Texture & Consistency: Similar smooth, rigid surface to standard styrene but with added flexibility and durability. Less brittle than standard PS.
- Workability: Easy to cut, saw, drill, and thermoform (especially good for vacuum forming complex shapes). It glues well with plastic cement (solvent glues).
- Finish: Takes paint readily.
- Excellent for parts that need to withstand more stress or repeated handling, such as RC body shells, durable structural components, and high-wear areas in models.
- Very popular for prototyping and vacuum forming custom parts.
- Available in various thicknesses, often in white or black, and larger forms.
Butyrate
Butyrate plastic (Cellulose Acetate Butyrate, CAB) is known for being a pliable, machinable, and durable material, making it ideal for applications requiring good formability and strength.
Characteristics:- Material: Cellulose Acetate Butyrate (CAB) thermoplastic.
- Texture & Consistency: Pliable and durable.
- Workability: Very convenient to work with. It can be cut, turned (lathe-turned in the same manner as brass or Cast Acrylic), drilled, tapped, carved, and sawn. Grind cutting tools to provide chip clearance; resultant turnings will have a polished surface. Very slow speed is required for machine sanding.
- Assembly: Easily cemented. Tubing and Tubing Fittings are manufactured to provide a good friction fit and maintain the outside diameter; splines on male Fittings accomplish tight fit and prevent undesired rotation while still allowing intentional turning. This feature permits cementing to be a final operation. Fittings can be more readily attached to Tubing, particularly in sizes 5/16” and over, if the pipe is screwed onto the Fitting (always rotate the Tubing in the same direction). The telescoping sizes combined with workability make improvisation quite simple.
- The material used in our Traditional Round Tubing, proving ideal for its workability.
- Suitable for parts requiring turning, drilling, or intricate shaping, especially where a durable and pliable material is needed.
- Often used for tubing and profiles in model making.
Clear & Transparent Plastics
These plastics are chosen specifically for their optical properties, allowing modellers to create windows, display cases, lenses, and other see-through elements with excellent clarity and varying degrees of durability.
Acrylic (Perspex)
Acrylic, widely known as Perspex in the UK, is a rigid, transparent thermoplastic renowned for its exceptional optical clarity, gloss finish, and weather resistance. It is the most rigid and brittle of these plastics.
Characteristics:- Material: Polymethyl methacrylate (PMMA) thermoplastic.
- Texture & Consistency: Crystal clear, glossy, and rigid. It can also be found in translucent or opaque colours. Usually warp-free.
- Optical Quality: Excellent light transmission, often clearer than glass.
- Workability: Can be cut with a fine-tooth saw or laser cutter (which provides very clean edges), drilled, and polished to a high sheen. It can be heat-formed. Glued with specialist acrylic cement (solvent weld).
- Finish: Accepts most paints, including lacquer.
- Essential for model windows, display cases, bases, clear structural elements, and components requiring optical clarity and a high-quality finish.
- Often used in tubing and thick forms, cubes and balls, and round, square, and triangular rod in model making.
- Popular for architectural models, bespoke enclosures, and art installations.
- Available in a wide range of thicknesses, forms, and colours.
Clear PETG (Copolyester)
Clear PETG (Polyethylene Terephthalate Glycol-modified), also known as Copolyester, is a transparent thermoplastic known for its outstanding toughness, impact resistance, and ease of thermoforming, making it a versatile alternative to acrylic. It is tougher and less prone to split or shatter than Acrylic.
Characteristics:- Material: Polyethylene Terephthalate Glycol-modified thermoplastic.
- Texture & Consistency: High clarity, smooth, and rigid, yet more pliable and less brittle than acrylic. It is resistant to stress whitening and not prone to warp.
- Durability & Resistance: Excellent impact resistance. Good chemical resistance. Quite stable.
- Workability: Very easy to cut, saw, drill, and especially well-suited for vacuum forming due to its good formability and less moisture absorption than other clear plastics. It bonds well to itself, but with most other plastics, a special industrial-grade Cyanoacrylate Glue is recommended.
- Finish: Accepts most paints, including lacquer.
- Used for windows, protective covers, custom enclosures, and parts that require a clear material with higher impact strength than acrylic.
- Popular in vending machine windows, medical packaging, and custom-formed model components.
- Commonly supplied in clear forms of various thicknesses.
Styrolux
Styrolux is a brand of transparent styrene-butadiene copolymer (SBC), offering a unique combination of crystal clarity and high impact strength, making it an ideal choice where transparency and toughness are both required.
Characteristics:- Material: Styrene-Butadiene Copolymer (SBC) thermoplastic.
- Texture & Consistency: Highly transparent, rigid, and smooth surface. Excellent optical properties comparable to acrylic.
- Durability & Workability: Significantly more impact-resistant than standard polystyrene, yet still easy to cut, drill, and glue. It can be thermoformed.
- Ideal for clear components in models that might experience some impact, such as windows in vehicles or display cases, clear structural elements, and protective covers.
- Used in applications where acrylic might be too brittle, or where a balance of clarity and toughness is essential.
- Typically available in clear forms of various thicknesses.
Clear PVC
Clear PVC (Polyvinyl Chloride) is a rigid, transparent plastic known for its good strength, chemical resistance, and often a slightly blue tint compared to other clear plastics.
Characteristics:- Material: Polyvinyl Chloride (PVC) thermoplastic.
- Texture & Consistency: Rigid, smooth, and transparent, often with a slight blue hue.
- Durability & Resistance: Good resistance to chemicals and moisture. Generally strong and rigid.
- Workability: Can be cut, drilled, and glued with PVC-specific cements. It can be heat-formed.
- Suitable for windows, transparent structural elements, protective barriers, and custom enclosures in models where clarity and rigidity are needed.
- Often used where chemical resistance is a factor.
- Available in various thicknesses and forms.
Acetate
Acetate, or cellulose acetate, is a flexible, clear plastic film or thin form, distinct from the rigid plastics by its pliability and often glossy finish.
Characteristics:- Material: Cellulose acetate polymer.
- Texture & Consistency: Flexible, smooth, and transparent film or thin form. Often has a high gloss.
- Workability: Very easy to cut with scissors or a craft knife. It can be bent, folded, and glued with various adhesives (e.g., PVA, superglue, clear tape). It can be printed on.
- Resistance: Less resistant to scratching than rigid plastics, and can yellow or become brittle over time with UV exposure.
- Ideal for small windows in models, overhead projector transparencies, art overlays, stencils, and creating miniature glazing effects where slight flexibility is an advantage.
- Common in traditional drafting and design.
- Typically supplied in rolls or thin forms, often in A4 or A3 sizes.
Engineering & Performance Plastics
These plastics offer enhanced mechanical properties such as toughness, impact resistance, and resilience, making them suitable for functional parts, high-stress components, and models that require greater durability.
ABS (Acrylonitrile Butadiene Styrene)
ABS has been hailed by professional model makers as ‘the best all-around construction material since wood’. It is a tough, rigid, and impact-resistant engineering thermoplastic, widely used for durable components and consumer products due to its strength and ability to be easily processed. Size for size, it is nearly as rigid as brass. Our ABS structural shapes by PLASTRUCT have been used for engineering design models on an international scale since their introduction, meeting specifications for stability with just the desired amount of flexibility to minimise shock.
Characteristics:- Material: Acrylonitrile Butadiene Styrene (ABS) thermoplastic terpolymer, combining the best qualities of the Acrylics, Butyrates, and Styrenes.
- Texture & Consistency: Rigid, opaque, and smooth surface, often with a slight sheen. Known for its toughness and good impact strength.
- Workability: Relatively easy to cut, drill, and machine. It can be thermoformed (vacuum formed) very well, making it one of the best plastics for heat or vacuum forming. Excellent for bonding not only to itself but to other commonly used plastics with ABS cement (solvent weld), creating strong bonds. PLASTRUCT Traditional Structural Shapes are carefully moulded and extruded to extremely close tolerance.
- Finish: Takes paint well. PLASTRUCT ABS requires no priming, sanding, or sealing to enhance its hard finish. Its lustrous surface is unaffected by most chemicals, even lacquer – a property unheard of in the early plastics.
- Resistance: Stronger and more rigid than many metals. Extremely resistant to most acids and alkalines.
- Used for durable model parts, structural components, casings, and elements that need to withstand wear and tear.
- Common in car dashboards, LEGO bricks, and appliance housings, indicating its suitability for robust model parts.
- Ideal for RC car bodies, robot chassis, and functional prototypes.
- Available in various thicknesses, colours, and forms.
Polypropylene (PP)
Polypropylene is a versatile and semi-rigid thermoplastic, notable for its excellent chemical resistance, fatigue resistance (can be bent repeatedly without breaking), and lightweight nature.
Characteristics:- Material: Polypropylene (PP) thermoplastic.
- Texture & Consistency: Flexible, waxy feel, and translucent to opaque. It has a slightly softer feel compared to ABS or styrene.
- Durability & Resistance: Excellent chemical resistance, especially to acids and bases. Highly resistant to fatigue (good for living hinges). Water resistant.
- Workability: Can be cut easily with a knife or scissors. It's challenging to glue effectively with standard adhesives; special PP glues or mechanical fasteners are often required. Difficult to paint without specialised primers.
- Ideal for flexible parts, living hinges (e.g., on model boxes), chemical-resistant components, and elements that need to endure repeated flexing or exposure to certain liquids.
- Used for small containers, flexible joints, or where the material's inherent flexibility is a key design feature.
- Available in various thicknesses, colours, and forms.
