Create Stunning Auto Lens with Resin and Silicone Molds

Table of Contents

1. Introduction
2. The Challenge of Finding Rare Auto Restoration Parts
3. The Importance of Mold Making and Casting
4. The Process of Reproducing Rare Auto Parts
   1. Prepare the Splitter Board and Mold Box
   2. Secure the Lens and Registration Keys
   3. Apply Mold Release and Pour Silicone
   4. Create the Second Half of the Silicone Mold
5. Casting the Reproduced Parts
   1. Preparing the Mold for Casting
   2. Choosing the Right Casting Material
   3. Tinting the Casting Urethane
   4. Mixing and Vacuum Degassing the Urethane
   5. Pouring and Curing the Cast Parts
6. Vacuum Degassing vs. Pressure Casting
7. Conclusion

How to Reproduce Hard-to-Find Auto Restoration Parts

Introduction

Restoring classic automobiles is a beloved hobby for many enthusiasts, but it can be quite challenging when it comes to finding rare replacement parts. Often, these hard-to-find parts can be expensive or simply unavailable in the market. However, with a little knowledge of mold making and casting, You can breathe new life into old parts and make them as good as new again. In this tutorial, we will guide you through the process of reproducing a brake taillight lens for a classic 1958 BMW Isetta 300. As a bonus, we will also Show you how to make a Rubber trim gasket for the convertible ragtop. So, let's dive in and unlock the mystery of materials!

The Challenge of Finding Rare Auto Restoration Parts

When it comes to auto restoration projects, finding rare parts can often be a significant hurdle. It's not uncommon to find one good part but struggle to find a matching pair or the quantity needed for a small business. This challenge becomes even more daunting when the parts are no longer in production or have limited availability. However, with the right knowledge and skills in mold making and casting, you can overcome these obstacles and create multiple sets of rare parts for your restoration projects.

The Importance of Mold Making and Casting

Mold making and casting play a crucial role in reproducing hard-to-find auto restoration parts. By creating a mold of the original part, you can replicate its Shape, texture, and even its glossy finish. The beauty of silicone mold making lies in its ability to capture even the finest details, allowing you to recreate the exact appearance of the original part. With the right casting material, you can produce multiple replicas that closely Resemble the original, ensuring a seamless restoration process.

The Process of Reproducing Rare Auto Parts

To reproduce rare auto parts, you need to follow a step-by-step process that involves preparing the mold, securing the original part, pouring the silicone, creating mold halves, and casting the reproduced parts. Let's break it down into detailed steps:

1. Prepare the Splitter Board and Mold Box

Before beginning the mold making process, you need to set up the splitter board and mold box. The splitter board defines where the mold will split into two halves, while the mold box contains the liquid silicone. Depending on the shape of the original part, you may need to build up the backside using modeling Clay. Once the splitter board is in place, you can lightly fasten the lens and registration keys using CA glue, ensuring proper alignment for the mold.

2. Secure the Lens and Registration Keys

To ensure the lens and registration keys are securely bonded to the splitter board, use a light spray of accelerator to create an Instant bond. Pay close Attention to the amount of glue applied, as only a tiny drop is needed. After bonding the keys, you can proceed to dry fit them to ensure proper layout and enough room between the lens and the mold box. Once satisfied, glue down the registration keys using small dots of CA glue.

3. Apply Mold Release and Pour Silicone

Before pouring the silicone, it's essential to clean the lens once more. Since silicone won't stick to a polished surface, there's no need to apply a mold release at this stage. However, the silicone will stick to itself, so mold release will be necessary later in the process. Cover the lens to prevent any Dust and carefully pour the two-part mold silicone, ensuring a steady stream and avoiding the creation of additional air bubbles. Fill the mold box to the top and allow the silicone to cure.

4. Create the Second Half of the Silicone Mold

Once the first half of the mold has cured, it's time to create the second half. Prepare another mold box using scrap pieces of wood and hot glue to hold everything together. Apply mold release to the exposed silicone to prevent any sticking, and then pour the second half of the silicone mold. Slowly and carefully fill the mold box, ensuring no air bubbles are trapped. After the silicone has cured, remove the mold box and carefully separate the two mold halves.

Casting the Reproduced Parts

With the silicone mold complete, it's time to cast the reproduced parts using the desired casting material. To achieve the best results, follow these steps:

1. Preparing the Mold for Casting

Before casting, it's necessary to spray an appropriate mold release onto the mold. However, in rare cases where a shiny surface is desired, you can opt not to use a mold release. While this may lead to a shorter mold life, it saves considerable labor time by eliminating the need for HAND polishing the cast parts later. Strap the silicone mold to a rigid board to prevent any flex during casting and angle the mold for optimal filling performance and air extraction.

2. Choosing the Right Casting Material

The choice of casting material is crucial for achieving high-quality reproductions. One excellent option for aftermarket automotive lenses is BJB WC783 Water clear polyurethane. This material offers unique UV inhibitors and natural color stability, resulting in a strong and impact-resistant finish. Consider the specific requirements of your restoration project and choose a casting material that best fits the desired characteristics of the reproductions.

3. Tinting the Casting Urethane

Depending on the original part's color, you may need to tint the casting urethane to achieve a perfect match. Perform a small test to determine the appropriate loading of translucent dye required to achieve the desired color. BJB PS-TF dyes are specifically designed to allow light to pass through the urethane, maintaining the desired transparency of the part.

4. Mixing and Vacuum Degassing the Urethane

To ensure a Bubble-free casting, thoroughly mix the water clear polyurethane, tinting as necessary. Once mixed, place the material in a vacuum chamber to extract any air bubbles that may have been incorporated during the mixing process. Vacuum degassing helps eliminate trapped air, ensuring a smoother and higher-quality cast.

5. Pouring and Curing the Cast Parts

After degassing, carefully pour the casting urethane into the mold, trying to avoid the introduction of any additional air bubbles. The use of a tall funnel facilitates a smooth flow, thanks to gravity. Lightly tap the mold to dislodge any minor air bubbles trapped inside. Allow the cast part to cure overnight before demolding. Depending on the specific casting material used, accelerating the cure with moderate heat may be an option.

Vacuum Degassing vs. Pressure Casting

When it comes to producing high-quality cast parts, the choice between vacuum degassing and pressure casting depends on the desired result. Vacuum degassing physically removes air bubbles from the material, while pressure casting compresses the air bubbles to a less visible state. It's essential to understand the characteristics of your casting material and the specific requirements of your project to determine which technique or combination of techniques is most appropriate.

Conclusion

Reproducing hard-to-find auto restoration parts is not as daunting as it may seem. With the right knowledge of mold making and casting techniques, you can recreate rare parts and bring classic automobiles back to their former glory. By following the step-by-step process outlined in this tutorial and utilizing suitable materials, you can produce high-quality reproductions that match the original parts in every Detail. So, embrace the challenge of restoring classic automobiles and Never let the scarcity of parts hold you back!

Highlights

• Restoring classic automobiles can be challenging due to the scarcity of rare replacement parts.
• Mold making and casting allow for the reproduction of hard-to-find auto restoration parts.
• Silicone molds capture detail and produce replicas with a glossy finish.
• The process involves preparing the mold, securing the original part, pouring silicone, and creating mold halves.
• Casting the reproduced parts requires selecting the right material, tinting if necessary, and vacuum degassing.
• Vacuum degassing and pressure casting techniques ensure high-quality cast parts.

FAQ

Q: Can I use other materials instead of silicone for the mold making process?\ A: Yes, while silicone is commonly used for mold making, other materials such as Legos, cardboard, or metal can also be employed.

Q: How do I ensure a perfect match with the original part's color?\ A: By performing small tests and adjusting the loading of translucent dye, you can achieve the desired color match.

Q: Can I skip the application of mold release on the silicone mold if I want a shiny surface?\ A: Yes, you can omit the mold release in this case, but be aware that it may reduce the mold's overall lifespan.

Q: What are the advantages of vacuum degassing and pressure casting?\ A: Vacuum degassing eliminates trapped air bubbles, while pressure casting helps force material into small air pockets and fine details.

Q: What is the recommended casting material for aftermarket automotive lenses?\ A: BJB WC783 water clear polyurethane is an excellent choice, offering UV inhibitor additives, natural color stability, and high impact resistance.