Custom Gear Manufacturing Services & Replacement Gear Engineering
Replacement and Custom Gears for Industrial Applications
Our custom gear manufacturing services are for OEM equipment, repair work, and replacement needs across multiple industries and applications.
Upload drawings, CAD files, or photos for review. If documentation is incomplete, our team has years of experience in manufacturing custom gears. We can reverse engineer from worn or failed components and rebuild to match original performance.
This includes a full range of gears, internal and external splines, shafts, and related precision components used in discontinued designs or equipment already in service. Each request is evaluated for geometry, material selection, load conditions, and tolerance requirements to ensure compatibility with existing systems.
When a critical part fails and a replacement isn't on the shelf, our team moves immediately to recreate the component and restore your operation. We specialize in:
- Broad Capabilities: Spur gears, helical gears, double helical gears, splines, and shafts.
- Problem Solving: Exact replacements for worn, damaged, or discontinued parts.
- No Drawings from OEMs? No Problem: Full reverse engineering from samples, fragments, or limited data.
- End-to-End Support: From custom gear manufacturing services to precision gear cutting to machining services, inspection and more.
For time-sensitive and emergency failures, priority is placed on review and production to help reduce downtime.
Manufacturing Capabilities, Support and Processes
Review equipment, materials, inspection standards, and assembly support used to manufacture and produce custom gears and replacement components.
In-House Manufacturing Capabilities
Our custom gear manufacturing capabilities are supported by in-house equipment for machining, gear cutting, and finishing. This allows tighter control over tolerances, scheduling, and part quality across both new production and replacement work. All processes are performed in-house to maintain control over geometry, fit, and turnaround for both new and replacement components.
The equipment below reflects the processes used to produce custom gears, from initial blanks through final grinding and inspection.
Turning
Eight CNC Mazak turning centers to support gear blanks across a range of diameters and lengths
- Controlled blank geometry for downstream gear cutting and finishing
- Multiple large capacity vertical turning centers for repeatability across low-volume and production work
Milling
- CNC milling used for keyways, bolt patterns, and mounting features
- Supports secondary machining required for gear integration
- Maintains dimensional accuracy for assembly and alignment
Hobbing
Gear shaping machines for internal and external gears. Specializing with support of complex geometries not suited for hobbing
Gear hobbing for spur and helical gears across multiple pitch range
Equipment includes a variety of large-format manual hobbers such as Phauter and G&E machines.
Shaping
Fellows gear shapers, including 36-inch machines with extended stroke and riser capacity
Supports internal and external gear profiles
CNC Fellows FS400-125 Hydrostroke shapers added for higher-quantity production
Precision Grinding
OD, ID, cylindrical, and surface grinding performed in-house
Precision grinding capability has been maintained internally since the late 1960s
Used to control blank geometry and surface quality prior to final gear grinding
Gear Grinding
Dedicated Gear Grinding Center
HÖFLER gear grinders equipped with on-board checking
Capable of grinding large-diameter gears
Operates extended hours to support throughput and emergency work
Supports AGMA Q15, DIN 2, and AGMA A2 quality requirements
EDM
EDM machining for internal features, splines, and keyways
Supports tight-tolerance geometries and complex profiles
Used where conventional machining is not feasible
Used where traditional broaching or pulling methods are not suitable
Supports internal spline profiles and tight-tolerance features
Gear Types and Components Manufactured
Our custom gear manufacturing services supports a range of gear types and precision-machined components used in industrial drive systems and power transmission applications.
Parts are produced from drawings, CAD models, or physical samples to match required geometry, tolerances, and operating conditions. This includes new components and replacement parts for equipment already in service, manufactured to specified tooth form, pitch, pressure angle, material, and heat treatment requirements.
Gear Types and Components Produced Include:
Components are produced to match existing systems or new application requirements, including helical gears, spur gears, worm gears, bevel gears, splines, shafts, and related components.
| Gear Type | Description | Typical Application |
|---|---|---|
| Spur Gears | Parallel shaft gears with straight tooth profiles | General industrial drives and conveyors |
| Helical Gears | Angled tooth gears for smoother engagement and load sharing | High-speed or high-load drive systems |
| Splines | Internal or external profiles for torque transmission | Shaft connections and coupling interfaces |
| Shafts | Precision-machined shafts with controlled diameters and fits | Gear mounting and rotational systems |
| Replacement Gears | Duplicate gears built to match existing geometry and fit | Maintenance, repair, and legacy equipment |
| Specialty Components | Custom-machined parts with non-standard geometry or features | Application-specific or engineered systems |
Frequently Asked Questions
What types of gears can be custom manufactured?
What types of gears can be custom manufactured?
Spur, helical, bevel, and custom gears can be manufactured based on application requirements. Components are produced from drawings, CAD models, or existing parts to match geometry, pitch, and system integration needs.
Can gears be manufactured without original drawings?
Can gears be manufactured without original drawings?
Yes, gears can be manufactured without original drawings by measuring existing components. This process captures tooth geometry, pitch, and critical dimensions to produce reverse engineered gears that match existing systems.
Material Inventory and Availability
We maintain a broad on-site inventory of domestically sourced U.S. steel to support fast production starts and dependable lead times. Keeping materials in-house eliminates delays from external sourcing and allows work to begin immediately once an order is released.
Our stocked materials offers full range of necessary materials including hardening alloys and carburizing grades commonly used in gear manufacturing, such as 4140, 4150, 4340, 8620, and 4320. A wide range of bar sizes is available to support both standard production and emergency replacement needs for a variety of gears such as, helical gears, spur gears, cycloidal gears, worm gears and bevel gears.
Material selection is approached with application performance in mind. Requirements such as load conditions, operating environment, heat treatment, hardness, and surface finish are evaluated to determine the most appropriate material for the component, ensuring the finished gear performs reliably in service.
Material selection is approached with application performance in mind.
Requirements such as load conditions, operating environment, heat treatment, hardness, and surface finish are evaluated to determine the most appropriate material for the component, ensuring the finished gear performs reliably in service.
Materials commonly used include:
- High-Strength US Alloys: Our gear solutions included extensive stock of domestically sourced 4140, 4340, and 8620 to ensure superior heat-treat response and structural integrity.
- Corrosion Resistance: Stainless steel options specifically for wash-down, food-grade, or harsh chemical environments.
- Wear-Resistant Grades: Specialized carburizing steels designed for maximum surface hardness and extended service life in high-load applications.
- 100% US-Sourced & Traceable: Supporting domestic supply chains with full material certification and traceability—ideal for BABA compliance and critical infrastructure projects.
- Ready-to-Ship Bar Stock: A wide range of diameters kept on-site to support both standard production and emergency "line-down" replacements.
Frequently Asked Questions
What materials are used for gear manufacturing?
What materials are used for gear manufacturing?
Gear manufacturing commonly uses alloy steels such as 4140, 4340, and 8620. Material selection is based on strength, wear resistance, and application requirements.
Does material availability affect lead time?
Does material availability affect lead time?
Yes, material availability directly affects lead time. In-stock materials reduce procurement delays and support faster production for both new and replacement gears.
Ensuring a Perfect Fit: Precision That Eliminates Rework
Inspection is integrated throughout Riverside’s manufacturing process and finalized prior to shipment or assembly. Verification focuses on critical-to-quality features to ensure each part meets customer specifications and their application.
Inspection capabilities include on-board gear checking, off-line gear checkers, precision centers, profilometers, Rockwell hardness testing, granite inspection plates, and a wide range of calibrated measuring tools. Inspection results are recorded and retained, with certifications available upon request.
This process supports tight tolerance requirements, including AGMA and DIN standards, while maintaining consistency across our custom and replacement components.
Inspection activities are structured around key verification steps throughout the process:
Inspection and Measurement
Inspection and Measurement
Inspection capabilities include on-board gear checking, off-line gear checkers, precision centers, profilometers, Rockwell hardness testing, granite inspection plates, and a wide range of calibrated measuring tools. Results are recorded and retained, with certifications available upon request.
CMM Inspection
CMM Inspection
Coordinate measuring machines (CMM) are used to verify critical dimensions and complex gear geometries that cannot be reliably measured with manual tools. This includes validation of bore alignment, concentricity, and positional tolerances required for proper fit and function.
CMM inspection is used where precision is critical, particularly for custom components and parts that need reverse engineering that must match existing equipment.
Gear Tooth Inspection
Gear Tooth Inspection
Gear tooth inspection focuses on verifying tooth profile, pitch, spacing, and alignment to ensure proper meshing, load distribution, and contact during operation.
This step is especially important for replacement components, where new gears must match existing parts to maintain performance and avoid premature wear.
Hardness Testing
Hardness Testing
Hardness testing is performed after heat treatment to confirm that material properties meet specified requirements. Both surface hardness and core hardness are evaluated to ensure proper wear resistance and load capacity.
This verification supports long-term performance by confirming that the material will perform as expected under operating conditions.
Final Inspection
Final Inspection
Final inspection is completed prior to shipment or assembly to confirm that all dimensional, material, and tolerance requirements have been met. Each component is reviewed to ensure it is ready for installation and will perform as intended in service.
Frequently Asked Questions
How is gear accuracy verified?
How is gear accuracy verified?
Gear accuracy is verified through inspection of geometry, pitch, and surface condition using calibrated measurement equipment. This ensures gears meet tolerance requirements for fit, alignment, and performance under load.
What standards are used for gear inspection?
What standards are used for gear inspection?
Gear inspection is performed based on application requirements, including AGMA standards and tolerance specifications related to fit, alignment, and load performance.
Ready-to-Install Gear Assembly: Minimizing Your Shop Time
Gear assembly is performed with a focus on fit, alignment, and functional performance across mating components. This includes assembly of gears on shafts and shaft pinions to improve accuracy and reduce downstream handling.
Gear Assembly Capabilities Include:
Gear assembly is performed with a focus on fit, alignment, and functional performance across mating components. This includes assembly of gears on shafts and shaft pinions to improve accuracy and reduce downstream handling.
Professional Shrink-Fitting: We use controlled heat and cooling processes to ensure a permanent, secure fit. This removes the risk of damaging critical components during assembly in your facility
Assembly is completed prior to final tooth grinding to ensure proper alignment of the pitch diameter to the shaft axis. This helps reduce runout, gear wobble, and orientation issues that can impact performance in service.
For replacement applications, assemblies are matched to existing equipment to maintain alignment and compatibility without requiring modification during installation. This includes support for spline manufacturing and repair to ensure proper interface alignment.
Each assembly is checked prior to shipment to confirm proper fit, alignment, and readiness for installation.
Emergency Gear Replacement
Rapid Production for Replacement Gears
When your equipment goes down, our response team takes over. We specialize in emergency gear replacement with rapid-turnaround manufacturing for critical failures where OEM parts are weeks away or no longer exist.
- Work From Anything: We can recreate high-precision gears from worn samples, broken fragments, or even hand-sketches.
- Immediate Production: or emergency failures, we streamline our internal workflow to prioritize your project. Our team focuses on moving your part through production as efficiently as possible to minimize your downtime.
- Zero-Rework: We focus on delivering a high-performance replacement that can be installed the moment it arrives—getting your drive system back in service without delay.
Frequently Asked Questons
What is included in gear assembly services?
What is included in gear assembly services?
Gear assembly services include mounting gears to shafts, verifying alignment, and preparing components for installation. This ensures proper fit, engagement, and performance before use.
Why is gear assembly performed before installation?
Why is gear assembly performed before installation?
Pre-assembly verifies alignment, fit, and engagement before installation. This reduces downtime and minimizes performance issues in the field.
Reverse Engineering and Obsolete Gear Replacement Services
4-Step Process for Gear Reconstruction and Replacement
1. Capture Geometry
Existing components are measured to capture tooth geometry, diametral pitch or module, pressure angle, and other critical dimensions required to match the original gear set.
Bore size, keyways or splines, and shaft interface conditions are documented to ensure proper fit and alignment.
2. Analyze Performance
Wear patterns, contact conditions, and load distribution are evaluated to understand how the gear operated under real service conditions.
This analysis confirms original geometry and highlights any adjustments needed to maintain or improve performance.
3. Material Optimization
Material grade, heat treatment, and hardness are reviewed based on the application and operating conditions.
Replacement gears are produced to match original specifications or updated as needed to address wear, loading, or service demands.
4. Dimensional Verification
Dimensional checks are performed throughout the reconstruction process to confirm geometry, tolerances, and alignment prior to final production.
Components are manufactured to specified tolerances and appropriate AGMA quality levels.