Rubber prototypes—crafted from materials like silicone, TPE, ТПУ, and natural rubber—are critical for validating product functions like elasticity, sealing, and slip resistance. Unlike plastic or metal prototypes, their production requires specialized mold-making and molding processes to leverage rubber’s unique flexible properties. This article breaks down the full process from demand analysis to final testing, with comparisons, technical tips, and real-world examples to help you avoid common pitfalls and create high-quality rubber prototypes.
1. Pre-Production: Define Requirements & Plan Design
Before starting fabrication, clarify testing goals and design parameters to ensure the prototype aligns with your needs. This stage lays the foundation for material selection and process choice.
1.1 Clarify Core Requirements
Rubber prototypes serve three key validation purposes—focus on these to guide your design:
| Requirement Category | Key Test Goals | Пример реального мира |
| Функциональная проверка | Test elasticity (НАПРИМЕР., “Can the waterproof ring bounce back after compression?”), sealing (НАПРИМЕР., “Does it prevent water leakage?”), and slip resistance (НАПРИМЕР., “Does the grip stay secure when wet?”). | A phone manufacturer tests a silicone waterproof ring prototype to ensure it seals the charging port during 30-minute water submersion. |
| Material Property Testing | Verify temperature resistance (НАПРИМЕР., “Will it withstand -30°C to 150°C for automotive use?”), износостойкость (НАПРИМЕР., “Does the tire tread avoid tearing?”), и твердость (30°–70° Shore). | An outdoor gear brand tests a TPE grip prototype to confirm it retains flexibility after 1,000 часов воздействия ультрафиолета. |
| Structural Compatibility | Ensure rubber parts assemble with metal/plastic components (НАПРИМЕР., “Does the rubber slot fit the plastic housing?”) and optimize thickness/chamfers to prevent deformation. | A medical device team adjusts the thickness of a silicone tube prototype from 1mm to 1.5mm to avoid kinking when connected to a plastic connector. |
1.2 Design 3D Models with Rubber-Specific Rules
Используйте программное обеспечение CAD (Солидворкс, Вкус, и) Чтобы создать цифровую модель, focusing on parameters unique to rubber:
| Design Parameter | Requirements & Советы | Причина |
| Скорость усадки | Account for rubber’s natural shrinkage (1.02–1,05%: silicone = 1.03%, polyurethane = 1.02%). | Prevents dimensional errors—e.g., a 100mm waterproof ring will shrink to 97mm if using silicone; model it as 103mm initially. |
| Толщина & Флажки | Keep thickness 0.5–5mm (too thin = easy tearing; too thick = slow curing). Add 0.5–1mm chamfers to edges. | A silicone shock pad prototype with 0.8mm chamfers avoids cracking when compressed, unlike a sharp-edged version that breaks after 50 пресс. |
| Anti-Slip Patterns & Отверстия | Mark anti-slip textures (НАПРИМЕР., grid patterns for grips) and assembly holes (НАПРИМЕР., 2mm diameter for screws) with clear coordinates. | A power tool handle prototype with 0.5mm-deep grid patterns passes slip tests—users report 40% less hand fatigue than a smooth-surface version. |
1.3 Split Complex Parts (При необходимости)
For curved or thin-walled rubber parts (НАПРИМЕР., a U-shaped sealing strip), split the 3D model into sections. This simplifies mold machining and prevents deformation during demolding. Например:
- A curved silicone earbud prototype is split into “ear tip” and “body” sections—each fits into a smaller mold, reducing the risk of air bubbles compared to a single large mold.
2. Создание формы: Choose the Right Method for Your Batch & Точность
Rubber prototypes require custom molds—select between CNC-machined and 3D-printed molds based on precision needs and production volume.
| Тип плесени | Process Details | Преимущества | Недостатки | Идеально подходит для |
| CNC Machined Mold | Use CNC to engrave steel or aluminum blocks; polish the surface to Ra0.8–Ra1.6 to reduce demolding friction. | Высокая точность (± 0,05 мм), многоразовый (500+ цикл), suitable for hard rubbers like EPDM. | Высокая стоимость (\(500- )2,000 за плесень), slow lead time (3–5 дней). | Маленькие партии (10–100 единиц) of high-precision parts (НАПРИМЕР., medical device seals). |
| 3D Printed Mold | Print resin (СЛА) или нейлон (СЛС) формы; post-process with sanding to smooth surfaces. | Fast lead time (1–2 дней), бюджетный (\(100- )300 за плесень), easy to modify for complex shapes. | Low durability (20–50 циклов), limited to soft rubbers like liquid silicone. | Single or small batches (1–10 единиц) сложных частей (НАПРИМЕР., irregular-shaped TPU overlays). |
Ключевой совет: Для прототипирования, start with a 3D-printed mold if you need to test 1–5 units quickly. Switch to a CNC mold if you require 20+ идентичные прототипы (НАПРИМЕР., for user testing).
3. Molding Process: Select Based on Rubber Type & Размер частично
The molding method determines the prototype’s precision, эластичность, и стоимость. Choose from three common processes based on your material and application:
3.1 Liquid Silicone Injection Molding (LSR)
- Applicable Materials: Liquid silicone (30°–70° Shore hardness).
- Process Steps:
- Mix liquid silicone (Часть а + Part B) в 1:1 соотношение.
- Inject the mixture into a preheated mold (150°C–200°C).
- Cure for 5–15 minutes (в зависимости от толщины).
- Demold and trim excess material.
- Преимущества: Высокая точность (ideal for micro-parts like phone waterproof rings), отличная эластичность, and no post-curing needed.
- Идеально подходит для: Transparent medical parts (НАПРИМЕР., infusion tube fittings) and high-precision seals.
3.2 Solid Rubber Pressing
- Applicable Materials: Natural rubber, Epdm, and silicone rubber sheets.
- Process Steps:
- Cut rubber sheets into the approximate shape of the mold cavity.
- Heat the sheets to 120°C–180°C to soften them.
- Press the softened rubber into the mold with 10–20 MPa pressure.
- Cool for 10–20 minutes, then demold.
- Преимущества: Бюджетный, fast for large parts (НАПРИМЕР., automotive shock absorbing pads), and suitable for aging-resistant materials like EPDM.
- Идеально подходит для: Sealing strips (НАПРИМЕР., Дверные прокладки) and large slip-resistant mats.
3.3 Polyurethane Casting (UR)
- Applicable Materials: Polyurethane elastomers (ТПУ, TPE).
- Process Steps:
- Mix AB components (смола + hardener) в 1:1 соотношение.
- Degas the mixture under vacuum (-0.1МПА) Чтобы удалить пузырьки воздуха.
- Pour the mixture into the mold slowly to avoid eddy currents.
- Лечение при комнатной температуре (24 часы) or heat (80° C для 2 часы).
- Преимущества: Mimics rubber’s flexibility, perfect for cladding metal/plastic parts (НАПРИМЕР., power tool handles with metal cores).
- Идеально подходит для: Overmolded prototypes (НАПРИМЕР., silicone-coated plastic buttons).
Сравнение таблицы: Molding Process Selection Guide
| Тип частично | Рекомендуемый процесс | Материальный пример | Время выполнения |
| Micro-seals (≤5 мм) | LSR | Liquid silicone | 1–2 дней |
| Large shock pads (≥200mm) | Solid Rubber Pressing | Epdm | 2–3 дней |
| Overmolded grips | Polyurethane Casting | ТПУ | 1–3 дней |
4. Пост-обработка: Refine & Enhance Prototype Quality
Rubber prototypes require targeted post-processing to fix defects, улучшить производительность, and add functional details.
4.1 Basic Trimming & Выслушивание
- Use a sharp blade or grinding wheel to remove excess rubber burrs (common around mold edges). Для мелких деталей, таких как силиконовые вкладыши., используйте пинцет, чтобы удалить крошечные заусенцы — избегайте шлифовки (может повредить мягкие резиновые поверхности).
4.2 Secondary Vulcanization (For Silicone)
- Запекайте силиконовые прототипы при температуре 150–200°C в течение 2–4 часов.. Этот шаг улучшает термостойкость. (к 30%) и устойчивость к старению (продлевает продолжительность жизни на 50%), критично для автомобильного или наружного использования. Например:
Прототип силиконового автомобильного уплотнителя., после вторичной вулканизации, выдерживает 150°C в течение 1,000 часов без закалки — против. 500 часов для необработанной версии.
4.3 Поверхностная обработка
Добавьте функциональную или декоративную отделку в соответствии с вашими потребностями.:
- Противоскользящее покрытие: Spray epoxy-based anti-slip paint on grips to boost friction (reduces slip by 60% for wet surfaces).
- Шелковая печать: Apply logos, hardness labels (НАПРИМЕР., “50° Shore”), or warning text (НАПРИМЕР., “Medical Grade”).
- Material Bonding: Use rubber-specific adhesives to attach rubber to metal/plastic (НАПРИМЕР., a nylon + rubber overlay for a tool handle).
5. Тестирование & Оптимизация: Validate Performance & Fix Issues
Test the prototype against your initial requirements, and address common problems like bubbles or deformation.
5.1 Key Test Items
| Тип теста | Как выступить | Pass/Fail Criteria |
| Elasticity Test | Compress the prototype to 50% of its thickness, выпускать, and measure recovery time. | Recovers to original shape in ≤1 second (НАПРИМЕР., a shock pad prototype passes this test). |
| Тест на герметичность | Submerge the prototype in water (for waterproof parts) or apply air pressure (for airtight seals). | No water leakage/air loss after 30 минуты. |
| Точность размеров | Используйте суппорт, чтобы измерить размеры ключей (НАПРИМЕР., diameter of a waterproof ring). | Error within ±0.1mm (meets most industrial standards). |
5.2 Solve Common Defects
| Дефект | Причины | Исправляет |
| Demolding Difficulty | High rubber elasticity, rough mold surface (Раствор >1.6), нет наклона. | Polish mold to Ra ≤0.8; add 1°–3° draft slope; use silicone-specific release oil. |
| Пузырьки | Air trapped in liquid rubber, fast pouring, no degassing. | Degas rubber under -0.1MPA вакуум; pour mixture slowly (≤5ml/second); use a mold with air vents. |
| Dimensional Deformation | Uneven mold temperature (±>5° C.), incorrect shrinkage rate. | Heat mold evenly (use a temperature-controlled oven); adjust 3D model size based on material shrinkage (НАПРИМЕР., добавлять 3% for silicone). |
6. Yigu Technology’s Perspective on Rubber Prototype Production
В Yigu Technology, we’ve found that the biggest challenge in rubber prototype making is balancing flexibility with precision—many clients rush to choose LSR for high precision but overlook cost for small batches. Our approach is to match processes to needs: for 1–5 units of complex parts, we recommend 3D-printed molds + polyurethane casting (fast and cheap); для 10+ Высокие детали, CNC molds + LSR (durable and accurate). Например, a medical client initially chose LSR for a single silicone tube prototype (расходы \(300), but we switched to 3D-printed molds + кастинг (расходы \)80) не жертвуя качеством. We also emphasize pre-testing material compatibility—e.g., ensuring TPE bonds well with ABS before overmolding—to avoid rework. Rubber prototypes thrive on attention to detail; small adjustments (like adding a 2° draft slope) can save days of troubleshooting.
7. Часто задаваемые вопросы: Common Questions About Making Rubber Prototypes
1 квартал: Can I use 3D printing directly to make rubber prototypes (without molds)?
А1: Rarely—most 3D-printed “rubber-like” parts (НАПРИМЕР., TPU filaments) lack the elasticity and sealing performance of true rubber. Molding processes (LSR, кастинг) are needed to leverage rubber’s natural properties. For simple concept tests, 3D-printed TPU can work, but for functional validation, use mold-made rubber prototypes.
2 квартал: How do I choose between silicone and TPE for my prototype?
А2: Choose silicone for high temperature resistance (до 200 ° C.) и прозрачность (НАПРИМЕР., медицинские устройства, phone waterproof rings). Choose TPE for better wear resistance and lower cost (НАПРИМЕР., схватки, игрушечные детали). Например, a baby bottle nipple prototype uses silicone (нетоксичный, теплостойкий), while a toy car tire prototype uses TPE (дешевле, долговечный).
Q3: Why does my rubber prototype have a sticky surface?
А3: Sticky surfaces are usually caused by incomplete curing (НАПРИМЕР., LSR отверждался при 140°C вместо 160°C.) или излишки разделительного масла. Исправляет: Повторно отверждайте прототип при температуре 160°C в течение 1 час; вытрите излишки масла безворсовой тканью. Для силикона, вторичная вулканизация также устраняет липкость за счет удаления остаточных низкомолекулярных соединений..