Liquid Silicone Rubber Injection Molding
Custom medical and consumer-grade LSR parts with consistent cosmetics and traceable quality.
- Materials & hardness: Shore A 10–80; transparent, tinted, and optical-grade options
- Capabilities: micro/thin-wall, LSR-to-thermoplastic overmolding, cold runner/valve gate, controlled-environment production
- Quality & delivery: full lot traceability from incoming material to shipment; FAI and dimensional reports available
Certifications ISO 9001:2015 | ISO 13485 | CTQ Inspections | ITAR
Custom Liquid Silicone Rubber Molding Services
Our LSR injection molding service turns your CAD into production-grade silicone rubber parts in 15 days.
What we commonly build
- IP-rated seals & gaskets (O-rings, frames, diaphragms)
- HMI components: keypads and soft-touch buttons
- LSR-to-thermoplastic overmolded grips on PC/PA/PP
- Transparent/tinted windows and light-transmitting logos
- Medical & baby-care contact parts with documented materials
All available across Shore A 10–80 with full lot traceability; FAI/dimensional reports on request.
Kemal LSR Injection Molding Capabilities
| Capabilities | Details |
|---|---|
|
Lead time |
Prototypes from 1–3 business days with 24-hour DFM feedback; production tools in 2–5 weeks
|
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Production options |
Domestic and international manufacturing; pilot to multi-cavity series |
|
Machines available |
Single, family, and multi-cavity LSR tools; side actions and hand-loaded cores |
|
Inspection & documentation |
FAI and dimensional reports; optional PPAP, CoC, RoHS/REACH statements |
|
Quality system |
ISO 9001; full lot-level material and process traceability |
|
Tool ownership |
Customer-owned with documented maintenance plan
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|
Mold cavity tolerances |
±0.005″ (±0.127 mm) on cavity machining, plus ±0.002″ per inch (±0.05 mm/25 mm) of nominal dimension to account for shrink. Critical features are cut steel-safe and finalized after T0/T1.
Note: Actual limits depend on grade, Shore A, and process window; confirmed at DFM. |
|
Part-to-part repeatability |
±0.10 mm (±0.004″) ; Cpk ≥ 1.33 on critical dimensions |
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Available mold types |
Aluminum or steel; cold runner/valve gate; vacuum vents; prototype to Class 101–105 production grades |
Manufacturing Specifications
Capability | US | Metric |
|---|---|---|
Max part size (L×W×H) | 29 in × 18 in × 14 in | 737 mm × 457 mm × 356 mm |
Max projected mold area | 120 sq in | 7742 sq mm |
Max part volume | 59 cu in | 967.6 cu cm |
Max depth from parting line | ≤ 4 in; deeper parts limited to smaller outline | ≤ 101.6 mm; deeper parts limited to smaller outline |
Minimum wall thickness* | 0.040 in (1.016 mm) for most thermoplastics | 1.016 mm |
Minimum hole/slot | 0.040 in / 0.020 in | 1.016 mm / 0.508 mm |
Draft (texture / polished)**
| ≥ 2° / ≥ 1°
| ≥ 2° / ≥ 1° |
Typical production tolerance*** | ±0.003 in/in cosmetic features | ±0.076 mm per 25.4 mm cosmetic features |
- Actual minimums depend on geometry and Shore A and will be confirmed during DFM;
- Optical/transparent zones may need dedicated gating and polish specs.
- Critical features are validated per drawing via FAI and capability studies (Cpk on request).
Liquid Silicone Rubber Materials
We supply and qualify medical-, consumer-, optical-, and specialty LSRs across Shore A 10–80. Every lot is documented for traceability (TDS, CoA, batch records).
Material type | Shore A range | Key attributes | Sterilization* | Typical uses |
|---|---|---|---|---|
Standard LSR | 30 / 40 / 50 / 60 / 70 | General-purpose, stable cosmetics, good tear | ETO, Steam, Gamma | Seals, gaskets, buttons |
Medical-grade LSR | 10–80 | ISO 10993/USP-class candidates, low volatiles, traceable | ETO, Steam, Gamma (grade-specific) | Grips, valves, patient-contact parts |
Optical-grade LSR | 20–70 | High transmission, low haze/yellowness, polishable | ETO, Gamma | Light pipes, indicator windows, logos |
Self-adhesive LSR | 20–70 | Bonds to PC/PA/PP with designed interlocks | — | Overmolded grips, seals on plastics |
Fluorosilicone (FVMQ) | 40–80
| Fuel/oil resistance, low swell | — | Auto/industrial seals in hydrocarbons |
High-tear / low-compression-set LSR
| 30–70 | Durable under flex and compression | ETO, Steam | Diaphragms, long-life seals |
Note: Share your target Shore A, sterilization method, and substrate (if overmolding). We’ll recommend a validated grade and provide the documentation package.
Our Surface Finish Capabilities
Finish code | Mold surface spec | Typical look on LSR | Best for | Notes |
|---|---|---|---|---|
SPI-A2 (High polish) | #2 diamond buff | Water-clear / glossy | Optical windows, light pipes, logo lenses | Gate/parting line kept away from optics; corner radius required; may increase demold force. |
SPI-B1 (Satin) | 600-grit paper | Low gloss / smooth | Consumer-facing cosmetics, keypads, buttons | Good balance of look vs. cost; hides minor knit lines. |
SPI-C1 (Matte) | 600-grit stone | Matte | General housings, non-optical surfaces | Lower cost; helps reduce visible scuffing. |
BB-1 (Light bead-blast) | Fine media over SPI-C1 | Fine texture for grip | Soft-touch grip zones, covers | Texture can mask flow marks; requires vacuum venting to avoid micro-bubbles. |
BB-2 (Medium bead-blast)
| Medium media over SPI-C1 | Deeper matte texture | High-grip areas | Higher demold force; confirm draft at DfM. |
NC-1 (Low-cosmetic) | Toolmarks minimized | Internal/hidden surfaces | Internals, non-view sides | Cost-efficient for non-critical areas. |
NC-0 (Non-cosmetic / EDM OK) | EDM/texturing permitted | Hidden features only | Inserts, undercuts, back sides | Not for view or optical zones. |
Upload your drawing with finish call-outs (SPI/BB). We’ll return DFM notes, draft requirements, and a cost impact for each finish zone.
Gallery of Molding Rubber Parts
Why Choose Kemal for LSR Injection Molding
25+ Years of Industry Experience
Start with a single set of samples or a short run—no minimum order required. Scale from pilot builds to multi-cavity production without switching suppliers.
- Pilot, bridge, and series production supported
- Tool transfers welcome (evaluation and refurb plan provided)
- Priority lead times for repeat orders
Comprehensive Material Support
- Standard Silicone (30, 40, 50, 60, and 70 durometers)
- Medical-Grade Silicone
- Optical-Grade Silicone
- Fluorosilicone (fuel and oil resistant)
Certification & Compliance Coverage
Our factory runs under ISO 9001 with lot-level traceability. You receive FAI and dimensional reports by default; PPAP, CoC, RoHS/REACH can be added on request.
Free DFM Analysis
Upload your CAD and get a Design-for-Manufacturability review in 24 hours—risk notes, tolerance targets, and a cost + lead-time plan—before you commit to tooling. For overmolding, we include an adhesion test plan if needed.
One-Stop Injection Molding Solutions
One partner from CAD → tooling → molding → inspection → packaging → shipping. Your project engineer keeps everything moving and delivers a complete document pack with each shipment.
Rich Experience & Expercise
Backed by 25+ years in mold making and LSR molding, our dedicated team guides your part from DFM to SOP—so prototyping and production stay on-spec and on schedule.
Complete Guide to Liquid Silicone Rubber Injection Molding
This guide walks through the essentials engineers ask about—DFM rules, material choices, bonding to plastics, finishes, and production tolerances—so you can move from prototype to production with fewer surprises.
Comprehensive Plastic Part Services
We provide early-stage design for manufacturability (DFM) analysis to optimize wall thickness, draft angles, and gate placement. This helps identify risks upfront and reduces costly mold changes later.
From single- to multi-cavity and hot runner molds, we build tooling that matches your production needs. Steel selection and surface finishes ensure durability and precision over the mold’s lifetime.
We offer standard molding, insert molding, and overmolding options. Each run is monitored with scientific process controls and full batch traceability to guarantee consistent results.
Choose from painting, pad printing, laser marking, and UV coating. ABS is especially well-suited for surface finishes, making it ideal for branded housings and visible parts.
Every part goes through strict IQC, IPQC, and OQC processes. We provide dimensional reports and compliance documentation to meet international standards.
From sub-assemblies to custom packaging, we streamline the final steps before shipping. Global logistics support ensures your parts arrive efficiently and ready to use.
Our Customers
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