6 Ways to Make Translucent and Transparent Parts

If you need a part that lets light pass through, you have a few options. Whether you’re making lenses, covers, or display panels, choosing the right method is important.

In this article, we’ll tackle more about 6 ways to make translucent and transparent parts.

What is a Transparent Material?

A transparent material lets light pass through completely, without scattering or blocking it. They do not absorb much visible light, which makes them clear.

Transparent materials also follow the rules of refraction (bending of light). They usually appear as a single color, but some can show a mix of colors, creating a beautiful spectrum.

Many liquids are highly transparent because they have no internal defects like cracks or gaps. Some materials allow almost all light to pass through with very little reflection. These are called optically transparent materials. Examples include flat glass and a camera lens.

What is a Translucent Material?

Translucent materials let light pass through, but not as clearly as transparent materials. They scatter the light, which makes objects on the other side appear blurry. They do not always follow the rules of refraction. This happens because of the way light interacts with the material’s surface, causing some of it to scatter.

Translucent materials are not as clear as transparent ones because they absorb more light. Examples include frosted glass, tinted glass, and wax paper.

Translucent vs Transparent Parts

Both transparent and translucent materials let light pass through, but they are not the same. Here’s how they differ:

Why Choose Translucent and Transparent Parts?

There are many reasons why product designers choose to make parts clear. Look around—you’ll probably see something transparent or translucent, like a window, a plastic cup, or a food container.

There are three main reasons for using clear materials:

To See Through It

Some things need to be clear so you can see what’s behind them. This includes windows, eyeglasses, plastic storage boxes, and ID card holders. These are usually fully transparent, meaning you can see everything behind them clearly.

To Let Light Through

Some objects need to be clear, not for human sight, but so light can pass through. Examples include greenhouse panels, solar panels, and terrariums. Things like flashlight covers or car headlamp covers also fall into this category. They don’t need to be fully see-through but must let light out.

For Looks

Sometimes, clear parts are used just because they look good. They don’t have a functional reason, but they make products more interesting. Examples include transparent gaming consoles, watches, musical instruments, designer bags, and some tool handles.

6 Ways to Make Translucent and Transparent Parts

Here are six ways to manufacture high-quality transparent and translucent parts:

1. SLA 3D Printing

Stereolithography (SLA) 3D printing uses a laser to harden liquid resin into a solid shape. This method produces smooth, detailed parts, but they may look frosted at first. To make them clear, you need to sand, polish, and apply a clear coat.

2. CNC Machining

Обработка на станках с ЧПУ cuts parts from a solid block of material. It works well for making super-clear parts, especially with acrylic or polycarbonate. Polishing is needed to remove tool marks and make the part completely see-through.

3. Urethane Casting

Urethane casting pours liquid plastic into silicone molds to create clear parts. This method is good for making small batches of parts that look like injection-molded plastic.

4. Injection Molding

Литье под давлением melts plastic and injects it into a mold. This is the best way to make large numbers of clear parts that are strong and smooth.

5. Vacuum Casting

Vacuum casting is similar to urethane casting but removes air bubbles using a vacuum. This makes the parts smoother and clearer.

6. Material Jetting (3D Printing)

Material jetting sprays liquid resin in tiny drops, which are hardened by UV light. This method is great for making detailed, clear parts, but polishing is needed for full transparency.

Materials Used for Translucent and Transparent Parts

There are different materials for making translucent and transparent parts depending on the manufacturing process. Check the table below for examples of materials for each process.

Factors To Consider When Choosing Material for Translucent and Transparent Parts

When choosing materials for translucent and transparent parts, keep these four factors in mind:

Оптическая четкость: Ensure the material allows light to pass through clearly. For example, акрил (PMMA) is known for its excellent clarity, so it is ideal for applications requiring transparency.

Mechanical Strength: Consider how strong and durable the material needs to be. Materials like polycarbonate offer high impact resistance, suitable for applications where durability is essential.

Thermal Resistance: Think about temperatures the material will encounter. Some materials can withstand higher temperatures without losing their properties.

UV Resistance: If the part will be exposed to sunlight, choose a material that resists UV light to prevent yellowing or degradation over time.

Translucent and Transparent Parts Design and Assembly

When making translucent and transparent parts, you need the right material, shape, and assembly, and these are explained below:

Transparency Needs

Think about how clear your material needs to be based on how it looks and works. If you’re making optical instruments, the material should be very clear with no distortions. For things like phone screens, you need both clarity and durability.

To get good transparency, pick materials with little to no natural color and use additives that help light pass through. Testing different materials and running simulations can help make sure your design looks good in different lighting.

Shape and Size Matter

The size and shape of your part can affect how easy it is to make and how clear it stays. Complicated shapes or big sizes can cause problems like uneven cooling and bending, which can make the material look cloudy.

To avoid this, try to keep walls thin and avoid sharp edges, so light can pass through more smoothly. Using testing tools and prototypes can help you find the best design while keeping your part strong.

Joining and Assembly

If your part connects to other materials, you need to make sure it stays clear. Use sealing methods like adhesive bonding or ultrasonic welding to keep out dust and prevent light from scattering.

When designing your part, plan for seals and gaskets so everything fits well and stays clear. Careful planning helps avoid problems that could make the material less transparent.

Post Processes for Translucent and Transparent Parts

After making transparent and translucent parts, you often need extra steps to improve their look and clarity. Below, we discuss how to polish and add color to clear parts.

Sanding

Sanding is a process where you use rough materials like sandpaper to smooth a surface. This helps create the right texture before other finishing steps like polishing, painting, or sandblasting.

If your part has a complex shape, sanding can still be useful, though getting a fully transparent finish is challenging. However, with enough effort, you can make it look as clear as glass.

Polishing and Fumigation

Polishing makes the surface smoother but doesn’t change the shape or size of the part. It works well for SLA and CNC acrylic parts, making them shinier and more transparent. However, CNC parts made from PC or PS may still look cloudy after polishing. In such cases, using acetone fumigation can help make them much clearer.

Spray Painting or Coating

If you need transparent or colored parts—like red transparent headlights or textured designs—you can use spray painting. This method is often used before mass production with injection molding.

By adjusting the paint’s location, color, and thickness, you can create different effects. Spray coating is also a quick way to make an object shinier and more transparent, hiding layers and protecting against UV exposure.

Resin Coating

For the clearest, smoothest finish, especially on flat surfaces, you can apply a thin layer of resin. This method helps remove scratches and uneven spots. Simply apply the resin with a syringe, letting it spread evenly over the part. The thinner and more even the layer, the better the results.

Coloring

Instead of just polishing, you can also add color to your transparent parts for a more attractive look. During molding, you can mix in textures, additives, or colorants. Common coloring methods for CNC-machined parts include tinting, sandblasting, and texture painting. Primary colors like red, green, and blue are often used, but you can also mix secondary colors.

Where Do You Use Translucent and Transparent Parts?

These are some examples of objects where you need transparent and translucent parts:

Transparent Parts:

• Glass (Windows, Spectacles)
• Prism
• Camera Lens
• Fish Tank
• Computer Screen (if made of glass)
• Sand Timer (Glass part)

Translucent parts:

• Colored Plastic Bottle
• Colored Balloon
• Tinted or Frosted Glass
• Tracing Paper
• Sunglasses

Заключение

The best way to make clear parts depends on your project. For prototypes, use SLA 3D printing or material jetting—they make smooth, detailed parts but may need polishing. For strong, clear parts, choose CNC machining or injection molding. CNC machining gives high clarity, while injection molding is best for large batches.

If you need only a few parts, urethane or vacuum casting work well. They create smooth, clear parts but aren’t as strong as injection-molded ones.

Need clear parts? DEK offers various manufacturing options, from CNC machining to 3D printing, to match your project needs. Contact us to find the best solution for you.