The translation of an approved drawing to final silicone tips on the production line is a simple process for many OEM engineers and product managers. The custom silicone tip prototype to production process is really a several technical gates, decision points and revisions that can extend timelines if not managed properly.
It’s from incomplete requirements that lead to tool changes, to first of sample adjustments, all the way through the process – risks are expected. From requirements to DFM, to tooling, to sampling, to validation, to mass production ramp, this guide covers the entire journey of an OEM silicone component development project, to give you realistic expectations, the right inputs, and the ability to keep your project on track.
Stage 1 – Project Intake and Requirements Definition
Creating a successful silicone tip project begins way before cutting mold steel. The first step is to collect all the information that is needed for the application and not go straight to the drawings. Suppliers must be aware of exactly how the tip will operate in the real world.
Information that needs to be prepared include:
- Mechanical contact with other parts of the system (metal nozzles, plastic barrels, glass tubes)
- Modes of Operation:Temperature range, Chemical exposure, Pressure, Cycle frequency
- Requirements from the regulatory field (food grade, medical biocompatibility, electrical properties)
- Design requirements that relate to aesthetics such as color, hardness and surface finish.
Translating Requirements into a Supplier-Ready Technical Brief
When translating Requirements, keep the following points in mind:The following are considerations when translating Requirements:
A good technical brief will include 2D drawings or 3D CAD files, with clearly defined tolerances, materials, samples of mating parts and compliance information. The teams that present complete briefs at this stage will advance through the stages much quicker than those teams who take time to tweak the details via e-mailing back and forth.
OEM teams that engage a supplier offering full-process support from concept to mass production early in the project tend to move through tooling and validation significantly faster than those who treat each stage as a separate transaction.
Stage 2 – Design for Manufacturability (DFM) Review
Once the requirements are known, this is the juncture that will save the project from costly downstream issues, the DFM review of custom molded silicone parts. This is where the manufacturer assesses the manufacturability, ease of molding and demolding and the ability to reproduce at proper tolerances.
Typical DFM warnings for silicone tips are lack of draft angles, wall thickness variation (which can lead to sink marks or inconsistencies in the cure), too tight of tolerances for molding and parting line location (which can impact function or appearance).
What Comes Out of a DFM Review
A drawing or formal DFM report will be sent to you which will be marked up with specific recommendations, explanations and proposed changes. This feedback is not criticism, just an input to the engineering process, which saves a lot of time and money. Typically the revised DFM needs to be signed-off prior to the start of tooling.
Stage 3 – Tooling Design and Mold Fabrication
Once the DFM is approved, the project enters silicone tip tooling and mold making timeline. Tool makers choose the right steel, mill the cavities with CNC, EDM the increasingly fine details in progress and apply appropriate venting and gating.
Lead time for silicone tip tooling is normally 3-6 weeks for basic single cavity silicone tip tooling and longer for more complicated multi-cavity production molds. Some of the reasons for extending the time include tight tolerances, surface textures that must be customized and high cavity counts in large volumes.
Single-Cavity Prototype Tools vs Full Production Tooling
It is often a great advantage to bring some prototype or bridge tooling to a project to help test the part design before hardened multi-cavity production molds are created. This method is particularly useful for medical applications or high precision applications, where multiple iterations of sampling are expected.
Stage 4 – First Samples and Dimensional Inspection
The first samples are arriving, and it’s an exciting, but realistic time. These parts are inspected for silicone tips, dimensional inspection per drawing, durometer, visual inspection for defects and basic fit.
It is normal that the first sample from a new tooling will not be 100% correct, it will need some adjustments. The main point is to determine whether the differences are in the tooling geometry or process parameters.
Reading First Sample Results and Deciding on Tool Corrections
If the dimensional variation is consistent, it probably means steel-safe adjustments and if the dimensional variations are random, it means that the process is in need of tuning. Good mold makers work in a “cut conservatively” manner, making incremental adjustments that leave some options for further improvement.
Stage 5 – Functional Validation and Application Testing
Approval of dimensions is not the final criteria. The silicone tip should be reliable in its working environment under the following conditions: fit testing, leak testing, dispensing accuracy, sterilization simulation and mechanical endurance cycles.
Iterating Design or Process Based on Functional Test Results
Schedule 2–3 rounds of sampling in your project schedule. Generally, Round 1 is about dimensions and simple fit, Round 2 on functional performance, and Round 3 may be needed for final confirmation prior to production approval.
At stage 6, the process is validated and the product is approved for production.
Stage 6 – Process Validation and Production Approval
Before committing to mass production, the manufacturing process itself needs validation. Process parameters are documented, capability studies (Cpk) confirm consistency, and golden sample sets are established as quality references.
Establishing Incoming Inspection Criteria at the OEM
At this stage establish your own incoming inspection plan, critical dimension, AQL sampling, visual acceptance criteria, and quick functional checks. Having clear criteria means there won’t be any future arguments and both will be working from the same standard.
Stage 7 – Mass Production Ramp and Ongoing Supply Management
Process has been validated, production has begun with first production lots being fully inspected. Good communication links for non-conformances, agreed lead times, and change control process become critical to long-term success.
Continuous Improvement and Design Updates
Field performance data may result in useful refinements that can be made to the geometry, material or hardness. As the volume of parts being manufactured increases, it may also warrant upgrading tooling for increased efficiency.
Realistic Timeline Summary and Planning Benchmarks
A practical example of a typical process from the prototype of the silicone custom tips to the product is presented, including the typical duration and the main actions taken:
| Development Stage | Typical Duration | Key OEM Action Required |
| Requirements & Brief | 1–2 weeks | Provide complete drawings and specifications |
| DFM Review | 3–7 days | Review and approve DFM recommendations |
| Tooling Fabrication | 3–6 weeks | Approve final tooling design |
| First Samples & FAI | 1–2 weeks | Review inspection report and samples |
| Functional Validation | 2–4 weeks | Perform application testing and feedback |
| Process Validation & Approval | 1–3 weeks | Approve golden samples and process docs |
| Production Ramp | 2–4 weeks (initial) | Inspect first production lots |
These timelines are based on reasonably full information at intake and little major design changes. Complicated geometry, regulations and several iterations of sampling can take a lot longer. Keeping your manufacturing partner well-informed from the start and early on helps to keep these timelines tight and quality on target.
Our team of experts has successfully helped many OEM customers navigate this process and successfully developed their products in medical, laboratory, and industrial applications. By knowing what happens in each phase, you can plan to succeed and provide high-quality, reliable custom silicone tips that can be used for performance and commercial purposes.
