

Precision & Commercial Spur Gears, Bevel Gears, Worm Gears, Racks, and Gear Assemblies
SDP/SI is a well-known manufacturer of high precision standard and custom spur gears, bevel gears, and worm gear pairs, for a wide range of applications. Our fine to medium pitch spur gears are manufactured for some of the most demanding customers in the aerospace, defense, and medical industries of today.
SDP/SI applies strict quality control throughout the entire manufacturing process. Comprehensive engineering experience enables us to offer the additional services of design review and / or value engineering toward the goal of manufacturing efficiency.
An on-site Class 10000 clean room is used for testing, assembly and packaging. NADCAP and customer approved facilities are used for casting, heat-treating, plating, and painting. We can machine in many materials including aluminum, brass, bronze, steel alloys, stainless steel and titanium as well as custom gears in Greek Ascoloy and Inconel. For more about our manufacturing capabilities
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Inch Gears
AGMA 12, 10, 9, and 8
Available Pitches: 120 thru 16
Pressure Angles: 20° and 14.5°
Metric Gears
ISO 5 - 9
Available Modules: 0.3 - 3
Pressure Angles: 20° and 14.5°
SDP/SI specializes in plastic spur gears, bevel gears and worms. Molded and machined plastic gears are offered in both inch and metric sizes. A wide assortment of various configurations, number of teeth and sizes are available. Standard catalog items include spur gears, gear racks, bevel gears, miter gears, flexiracks and pinions, and worm gear sets. If a standard component does not meet your application needs, modifications or customized parts can be designed, engineered, and manufactured to your exact specifications.

SPUR GEARS:

AVAILABLE IN:
Materials: Stainless Steel, Aluminum, Brass, Nylon,
Acetal, Bakelite
Pitch: 16 - 120
Module: 0.4 - 3
Pressure Angle: 14.5 & 20°
Spur Gears have straight teeth and are usually mounted on parallel shafts. They are the simplest in design and the most widely used. External spur gears are the most common, having their teeth cut on the outside surface, also available are internal spur gears and rack and pinion gears. Spur gears can be found in instruments and control systems.
ANTI-BACKLASH GEARS:

AVAILABLE IN:
Materials: Stainless Steel, Aluminum
Pitch: 24 - 120
Pressure Angle: 20°
Anti-Backlash Gears are used in precision applications where little or no backlash is required. SDP/SI's fine pitch anti-backlash gears are designed using Stainless Steel Springs for tensioning and are available in clamp, pin or Fairloc® hub styles. Many types of gears can feature the anti-backlash attribute, the most common being spur gears.
BEVEL GEARS:

AVAILABLE IN:
Materials: Stainless Steel, Aluminum, Brass, Nylon, Acetal
Pitch: 24 - 48
Module: 0.5 - 3
Pressure Angle: 20°
For intersecting shafts, Bevel Gears offer a good means of transmitting motion and power. Most transmissions occur at right angles, but the shaft angle can be any value. Ratios up to 4:1 are common, although higher ratios are possible as well. The pitch surface of mating bevel gears is cone shaped.
PRECISION FAIRLOC® BEVEL GEARS:

AVAILABLE IN:
Materials: Stainless Steel, Aluminum
Pitch: 48 - 72
Pressure Angle: 20°
Bore Size: 1/8, 3/16, 1/4
SPECIFICATIONS: Socket Head Cap Screw Supplied. Fairloc® hubs require controlled shaft tolerances. Suggested clearance fit between the bore and the shaft is .0001/.0008. Available on special order: Teeth not listed, different pitch, bore size, passivation. Sold as a Set
SHAFT/HUB CLAMPS FOR SPLIT HUB GEARS AND PULLEYS:

AVAILABLE IN:
Materials: Stainless Steel, Steel
Shaft/Hub Clamps are designed to hold split hub gears and pulleys to the shaft in many applications. Precision and commercial grade clamps are available in one and two piece balanced construction and reduced clearance radius types. Screw-type shaft/hub clamps are offered for shafts as small as 1/16". All our clamps allow easy adjustment and removal of the gear or pulley on the shaft.
CLUSTER GEARS:

AVAILABLE IN:
Materials: Stainless Steel
Pressure Angle: 20°
Pitch: 48 - 80
Cluster Gears are a unit of spur gears of various diameters mounted on a shaft. Gears assembled in this arrangement are most often used in gearboxes for a variety of applications, including automotive.
COMPOSITE SPUR GEARS:

AVAILABLE IN:
Materials: Cast Nylon with Stainless Steel Core
Pitch: 48
Pressure Angle: 14.5° & 20°
SDP/SI offers a wide variety of gear types and materials, including Composite Gears. Composite gears are non-metallic gears cast around a knurled metal core. These lightweight gears can run at high speeds without lubrication while reducing noise, vibration and shock. They are corrosion and chemical resistant and do not absorb moisture. Composite gears can replace Stainless Steel gears in applications where high torque is required.
DIFFERENTIALS:

AVAILABLE IN:
Materials: Stainless Steel
Pitch: 72 - 96
Our design, engineering and manufacturing expertise is not limited to precision gears, but includes custom gearboxes, planetary gearheads and differentials. Our precision gears and gear assemblies meet the critical tolerances and functionality that the aerospace, defense and medical industries demand.
DIFFERENTIAL END GEARS:

AVAILABLE IN:
Materials: Stainless Steel, Aluminum
Pitch: 48 - 96
Pressure Angle: 20°
SDP/SI builds small Stainless Steel differentials in the following pitches: 96, 72, 64, 48 and are available as standard catalog items. Differential End Gears, Stainless Steel or Anodized Aluminum, will be assembled, free of charge, to differentials when ordered at the same time. 10 arc minutes maximum backlash between end gears.
GEAR AND DIAL HUBS:

AVAILABLE IN:
Materials: Stainless Steel, Aluminum
Precision Stainless Steel Gear and Dial Hubs are available in three hub types: clamp, pin and Fairloc®. The Fairloc® hub requires controlled shaft tolerances; suggested clearance fit between the bore and the shaft is .0001/.0008. An anodized aluminum pin type gear hub is also available for use with stamped or molded hubless gears or disc and drum dials.
GEAR BLANKS - NONMETALLIC:

AVAILABLE IN:
Materials: Acetal with Aluminum / Brass insert
SDP/SI manufactures a variety of gear types, including spur gears and internal gears. When making a spur gear the gear teeth are cut on the outside of a gear blank while internal gears are made by cutting gear teeth on the inside diameter of a gear blank. SDP/SI offers gear blanks as well as standard gears that are available in a wide range of teeth, bore sizes and pitches.
HELICAL GEARS:

AVAILABLE IN:
Materials: Stainless Steel, Aluminum, Hardened Steel
Pitch: 48
Pressure Angle: 20°
Module: 1 - 2
Helical Gears differ from spur gears in that its teeth are twisted along a helical path in the axial direction. It resembles the spur gear in the plane of rotation, but in the axial direction it is as if there were a series of staggered spur gears. This design brings forth a number of different features relative to the spur gear, two of the most important being:
1) Tooth strength is improved because of the elongated helical wrap-around tooth base support.
2) contact ratio is increased due to the axial tooth overlap.
Helical gears thus tend to have greater load-carrying capacity than spur gears of the same size.
INTERNAL GEARS:

AVAILABLE IN:
Materials: Stainless Steel, Aluminum, Brass
Pitch: 24 - 96
Module: 0.5 - 1
Pressure Angle: 20°
A special feature of spur and helical gears is their capability of being made in an internal form, in which an Internal Gear mates with an ordinary external gear. This offers considerable versatility in the design of planetary gear trains and miscellaneous instrument packages. Advantages of an internal gear are the following:
1) Well suited to compact design since the center distance is less than for external gears.
2) A high contact ratio is possible.
3) Good surface endurance due to a convex profile surface working against a concave surface.
MITER GEARS:

AVAILABLE IN:
Materials: Stainless Steel, Aluminum, Brass, Acetal
Pitch: 16 - 72
Module: 0.5 - 3.5
Miter Gears are a type of bevel gear designed to work in pairs. A miter gear set has a 1:1 ratio, identical dimensions and number of teeth. Miter gear sets are found in applications where input and output rotational speed of the drives does not vary but direction changes.
PINIONS, PINION SHAFTS, & PINION WIRE:

AVAILABLE IN:
Materials: Brass, Steel
Pitch: 24 - 64
Module: 0.4 - 0.8
Pressure Angle: 20°
SDP/SI Pinion Wire is extruded and can be used to make spur gears when a stock gear is not available. Available in brass and steel in the following pitches: 64, 48, 44, 32 and 24 (Modules 0.4, 0.5, and 0.8), 14–1/2° and 20° pressure angle. Pinion wire is offered in 1, 3, and 5 foot lengths as a standard catalog item. Other lengths are available on request. Steel Spur Gear Stock is also offered in pitches: 48, 32, 24 and 20 (Modules 0.8 and 1) and is used to make spur gears.
RACK & JOINING GAUGES:

AVAILABLE IN:
Materials: Stainless Steel, Aluminum, Nylon, Acetal
Pitch: 1/20 - 120
Module: 0.3 - 3
Circular Pitch: 2 & 5
Pressure Angle: 20°
Precision Racks are the straight or flat portion of a rack and pinion gear system, the pinion being the round gear. Teeth are cut into the rack that meshes with the pinion resulting in smooth, precise linear motion.
RATCHETS & PAWLS:

SPLINES INTERNAL & EXTERNAL:

WORMS & WORM GEARS:

AVAILABLE IN:
Materials: Stainless Steel, Bronze, Steel, Aluminum, Nylon, Acetal
Pitch: 24 - 64
Module: 0.5 - 3
Worms and Worm Gears work as a pair, rotating on shafts at 90°. Worm meshes are characterized by high velocity ratios. Also, they offer the advantage of the higher load capacity associated with their line contact in contrast to the point of contact of the crossed-helical mesh.