Uses for Plastic Cement in Model Building

Plastic cement is an essential tool in the world of model building, especially when dealing with plastic kits. This type of adhesive is not just a simple glue but a solvent that melts the plastic surfaces slightly, creating a strong bond as it cools and hardens.

Model builders often choose plastic cement for its ability to form durable, seamless joints.

When working with intricate models, builders appreciate the precision that plastic cement offers.  Its fine-tip applicator allows for careful placement of the adhesive, which is crucial for assembling detailed parts without creating a mess.

Plastic cement is especially effective for scratch building, where custom parts are crafted and assembled to create unique models.  For those involved in the hobby of 3D printing and scratch building, plastic cement provides a strong bond that outperforms other adhesives.

Whether it’s assembling small components or piecing together large sections, the reliability of plastic cement ensures that the finished model is both sturdy and meticulously crafted.

Understanding Plastic Cement

Plastic cement is an important adhesive in model building, especially for assembling plastic models and model kits. It boasts specific properties and comes in varying types that cater to different needs, ensuring precise and strong bonding.

Definition and Basic Properties

Plastic cement is a specialized adhesive designed for bonding polystyrene, commonly used in model kits. Unlike regular glue, plastic cement works by softening the plastic surfaces, causing them to weld together and form a strong, durable bond.

Key Properties Include:

  • Viscosity: Available in different viscosities to suit various applications.
  • Drying Time: Typically has a moderate drying time, allowing for adjustments.
  • Strength: Creates a robust bond ideal for plastic models.

Plastic cement often comes in bottles with fine applicator tips to provide precision in application, minimizing excess adhesive spreading.

Types and Varieties

Plastic cement comes in several types, each suited for specific tasks in model building.

Tamiya Extra Thin Cement:

  • Viscosity: Very thin, making it ideal for small, intricate parts.
  • Applicator: Includes a small brush for precise application.

Regular Plastic Cement:

  • Viscosity: Slightly thicker than extra thin cement.
  • Use: General purpose, good for most model assembly tasks.

Quick Setting Cement:

  • Drying Time: Faster drying, reducing wait times.
  • Application: Useful for parts that need quick assembly.

Other common adhesives used alongside plastic cement include cyanoacrylate (super glue), PVA glue, and epoxy glue, each having their own strengths and uses in model building.

Applying Plastic Cement

Applying plastic cement properly ensures strong, neat bonds.

  1. Preparation: Clean the surfaces to be joined, ensuring they are free from dust and grease.
  2. Application: Use the fine applicator or a toothpick to apply cement sparingly to one surface.
  3. Joining: Press the parts together and hold them until the cement sets.

Drying Time: Generally, plastic cement dries within minutes but reaches full strength in a few hours. For best results, follow the manufacturer’s instructions.

Achieving precision in application is crucial. Too much cement can lead to messy joints, while too little may not bond sufficiently.

Preparing Model Surfaces

Paint job with red metal airbrush spray paint gun on red scale model modern white blue passenger airplane

Preparing model surfaces ensures strong adhesion and a smooth finish. This involves cleaning and sanding, followed by priming to facilitate the plastic cement bond.

Cleaning and Sanding

Cleaning the model kit’s surfaces is crucial to remove dirt, oils, and residues. Use mild soap and water or isopropyl alcohol to clean the parts. Make sure to dry each piece thoroughly before proceeding.

Sanding smooths out imperfections and creates a better surface for adhesion. Use fine-grit sandpaper (around 400 to 600 grit) for plastic surfaces. Focus on areas with mold lines or rough spots. Sand gently to avoid damaging delicate parts.

For High-Impact Polystyrene (HIPS) kits, sanding helps create tiny grooves in the plastic. These grooves enhance the surface for liquid cement application, improving the strength and durability of the bond.

Priming for Adhesion

Priming the model surfaces prepares them for effective cement adhesion. Use a plastic primer designed specifically for model kits. Apply the primer in thin, even coats. This can be done using a brush or an airbrush, with the latter providing a smoother finish.

Allow the primer to dry completely before applying plastic liquid cement.

Primer helps by filling tiny gaps and creating an even surface, making the adhesive process more effective. It also enhances the overall durability of the glued parts.

The Gluing Process

Glueing Glass Pieces

When building plastic models, the gluing process can greatly affect the final outcome. It’s important to use the right techniques, focus on precision, and know how to correct mistakes effectively.

Techniques for Different Materials

Different materials require different gluing techniques for the best results.

Plastic cement is ideal for polystyrene pieces as it melts the surface slightly to form a strong bond.

Cyanoacrylate (super glue) works well for small, intricate parts but may cause cloudiness if used on clear parts.

For clear parts like windshields or canopies, it is best to use canopy glue or Micro Kristal Klear to avoid the fogging that other glues can cause.

Epoxy resins are useful for bonding different types of materials such as plastic to metal or wood, offering durability and strength.

Precision and Accuracy

Precision is key in model building. The right tools can help achieve clean and accurate glue applications.

Precision applicators or fine-tip bottles allow for the exact placement of glue with minimal waste. This prevents unwanted glue from messing up the details.

A steady hand and careful alignment of the parts before gluing are crucial. Light clamping or holding the parts in place for a few seconds ensures a strong bond.

Using too much glue can result in excess that may marring the model’s appearance.

Correcting Mistakes

Mistakes are common but fixable in model building.

If excess glue spills onto the model, removing it quickly is important. For plastic cement, smooth it out carefully before it dries. For super glue, an acetone-based remover can help dissolve it.

When pieces don’t fit right or are misaligned, disassembling gently and reapplying the glue correctly is necessary.

With epoxy resins, time is of the essence since they set slowly, allowing adjustments before hardening.

Advanced Techniques and Tips

When working with plastic cement in model building, achieving the best results requires some advanced techniques. Understanding how to create strong bonds, handle specific parts, and make custom modifications can take your models to the next level.

Creating Strong Bonds

To create strong bonds, it’s essential to use the right type of cement and apply it correctly.

Tamiya Extra Thin Cement is highly effective for creating strong joins in polystyrene plastic models. The fine tip applicator allows precise application, ensuring the cement seeps into the joints for a secure bond.

Two-part epoxy can also be used for parts that need extra strength. This glue is mixed before application and sets very strong, making it ideal for load-bearing sections.

Always ensure surfaces are clean and dry before applying any adhesive to maximize bond strength.

Dealing with Specific Parts

Different parts of a model require different techniques.

Clear parts, like windows and canopies, should be glued with white glue or clear-part cement to avoid fogging. Applying a small amount and allowing it to dry completely ensures transparency is maintained.

When working with intricate details, thin plastic cement is preferred. It flows easily into tight spaces without adding bulk.

For large components, general model cement provides a good bond but requires more drying time. Always clamp or tape parts together while they dry to maintain alignment.

Custom Modifications

For custom modifications, using fillers and additives can help achieve a smooth finish.

Applying putty to fill gaps between parts and then sanding ensures a seamless appearance. Mixing small amounts of polystyrene plastic with Tamiya Extra Thin Cement creates a strong filler for gaps that may otherwise be too large to seal effectively.

Model cement can be used to attach scratch-built parts. Use small amounts to avoid excess glue that could mar the finish.

For reinforcing joints, consider using two-part epoxy for areas that will be painted over, creating an unbreakable bond that will support the added weight of modifications.

Safety and Best Practices

When using plastic cement in model building, it is crucial to prioritize safety measures and follow best practices to ensure a secure and efficient working environment. Key considerations include proper ventilation, fume management, and careful handling and storage.

Ventilation and Fume Management

Ensuring adequate ventilation is essential when working with plastic cement, such as Tamiya Plastic Cement. The fumes from plastic cement can be harmful if inhaled over a prolonged period.

Recommendations to ensure proper ventilation:

  • Work in a well-ventilated area, ideally near an open window or with a fan to circulate air.
  • Use an exhaust fan or a fume extractor to remove fumes from the work area.
  • Consider working outdoors when possible. This is especially important when using strong adhesives like Gorilla Glue, which can have more potent fumes.

Additional tips for reducing fume inhalation:

  • Wear a mask designed to filter out chemical fumes.
  • Take regular breaks to get fresh air, especially during extended work periods.
  • Avoid working in confined or enclosed spaces without ventilation.

Handling and Storage

Proper handling and storage of plastic cement are vital for safety and maintaining the product’s effectiveness.

Instructions for safe handling:

  • Always wear protective gloves to prevent skin contact, as some adhesives can cause irritation or burns.
  • Avoid eating, drinking, or touching your face while using plastic cement.

Tips for secure storage:

  • Store plastic cement in a cool, dry place, away from direct sunlight and heat sources.
  • Keep the adhesive in its original container with the lid tightly closed when not in use.
  • Ensure that the storage area is out of reach of children and pets to prevent accidental ingestion or exposure.

Choosing the Right Cement for Your Project

Selecting the appropriate adhesive for your model-building project is crucial for success.

Types of Glue

Several types of glue are used in model building:

  • Plastic Cement: Ideal for plastic models.
  • Super Glue® (cyanoacrylate): Provides quick bonding but can cloud clear parts.
  • Liquid Solvents: Fuse plastic pieces together.

Advantages of Plastic Cement

Plastic cement offers a strong and durable bond. It works by slightly melting the plastic surfaces and welding them together. This ensures a seamless and solid connection.

  • Precision Application:  For precise work, use a brush applicator or fine-tipped bottle. This ensures the glue goes exactly where needed, avoiding mess and excess glue.
  • Penetration Techniques:  When using plastic cement, hold the parts together and let the cement wick between them. This method guarantees strong penetration and bonding.

Best Glue for Clear Parts

For clear plastic parts like windows, avoid Super Glue® due to its tendency to cause cloudiness. Instead, opt for a specialized glue designed for clear plastics.

Finishing and Post-Gluing Treatments

After gluing your plastic model kits, it is important to properly finish and treat the model for a polished appearance. This involves sanding to remove excess adhesive and painting to enhance the model’s look.

Sanding Post-Gluing

Once the plastic cement has dried, there may be excess glue or slight misalignments on the model. Sanding helps to smooth these areas. Use fine-grit sandpaper, usually around 400 to 600 grit, to gently sand the joints where glue was applied.

When sanding, make sure to move in one direction to avoid scratching the plastic. Also, constantly check to ensure you are not removing too much material. For tight spaces and small parts, consider using specialized sanding sticks or files.

This careful sanding process will produce a smooth finish, preparing the model for painting.

Painting and Sealing

After sanding, the model is ready for painting. Apply a primer first to create a uniform surface, which helps the paint adhere better. Once the primer is dry, you can start painting. Use acrylic or enamel paints specifically designed for plastic models.

Paint in thin layers to avoid drips and achieve a smooth finish. It’s best to use multiple thin coats rather than one thick coat. Pay attention to detail and ensure even coverage.

Once the paint is completely dry, apply a clear sealant. This protects the paint and adds a finished look to your model. Sealants can be matte, gloss, or satin, depending on the desired finish.

Troubleshooting Common Issues

When working with plastic cement in model building, several issues can arise. These include cracks, adhesive strength, fumes, and residue. It’s important to address these problems to ensure your models look their best and remain durable.

Preventing and Repairing Cracks

Cracks often occur due to incorrect application or excessive force during assembly. To prevent cracks, apply consistent pressure when gluing parts together and avoid bending pieces.

Use a brush to evenly apply cement along the edges for a solid bond without overloading.

If cracks do appear, a mixture of plastic cement and plastic scraps can create a filler. Apply this filler into the cracks and allow it to dry fully. Then, sand the area smooth for a seamless finish.

Choosing a flexible cement can also help reduce brittleness and future cracking.

Managing Adhesive Strength

Getting the right adhesive strength is crucial. If your cement is too weak, the parts won’t bond securely; too strong, and it may warp or melt the plastic. Test different brands like Tamiya or Testor’s to find one that suits your needs.

Control the adhesive’s strength by monitoring the amount you apply. Lighter applications prevent excess cement from weakening the material.

For heavy-duty parts, you might use CA glue to achieve greater strength. Ensure that the bond is adequate by letting the pieces sit undisturbed until fully set.

Avoiding Glue Fumes and Residue

Plastic cement can release fumes that are harmful if inhaled. It’s important to work in a well-ventilated area. Ideally, use a fan to keep the air circulating. Some modelers opt to wear masks to further minimize inhalation risks.

Residue from dried glue can ruin the appearance of the model. Carefully apply cement using brushes or applicators to control spread. Clean excess glue immediately with a cloth or paper towel. For stubborn residues, sanding down the affected area can help achieve a clean finish without damaging the model.