Rack & Pinion Systems

Pinion Gears

Pinion Gears

Welcome to the widest range of standard racks & pinions in the World!  Consisting of both helical & straight (spur) tooth versions, in an assortment of sizes, materials and quality levels, to meet almost any axis drive requirements.

These drives are perfect for a wide range of applications, including axis drives requiring precise positioning & repeatability, traveling gantries & columns, pick & place robots, CNC routers and material handling systems.  Heavy load capacities and duty cycles can also be easily handled with drives.  Industries served include Material Handling, Automation, Automotive, Aerospace, Machine Tool and Robotics.

The pinion product range consists of metric pitches from module 1.0 to 12.0, in various styles including helical, straight (spur), ISO flanged, split-pinion (zero backlash) and circular pitch. Quality levels available include soft, induction-hardened and hardened & ground (up to AGMA 12+ and DIN 5).

Typical delivery time for these standard components is 2 to 3 weeks, which is ideal for OEM's requiring just-in-time delivery schedules.  Special and/or modified components are always possible - please consult the factory.

Advantages of Using Small Pinions:  When it comes to selecting a pinion for use in a rack & pinion drive system, the pinion diameter has a huge effect on the system, including the gearbox torque, size, ratio, linear backlash, linear stiffness and resonant frequency of the system.

  • Pinion Styles
  • Pinion Gear Quality
    Levels Overview
  • Pinion Range
  • Lubrication

There are five basic pinion gear styles available (click on style for PDF catalog pages):

Helical Straight ISO Flanged Split-Pinion Circular Pitch
These pinions have the teeth at an angle (19º 31' 42") for increased load capacity and quiet operation. These pinions have the teeth perpendicular to pinion side, and are traditionally known as "spur". These pinions were designed for mounting directly to ISO 9409-1 flanged reducers. These pinions have two pinion halves which are spring-loaded against each other to provide zero backlash These pinions have a circular pitch from tooth to tooth, such as 5, 10 and 13.33 mm.

A Compression Coupling can be used on pinions with side hubs to attach the pinion to the shaft without any backlash.  This option, which can be used in conjunction with a key, is best for applications with high reversing cycles and eliminates the possibility of fretting corrosion.

Helical versus Straight:  The helical style provides several key benefits over the straight style, including:

  • They run quieter than the straight, especially at high speeds
  • They have a higher contact ratio (the number of effective teeth engaged) than straight, which increases the load carrying capacity
  • In most cases, they cost the same as the straight pinions!

The only possible disadvantage to using helical rack & pinions is that they could require more time to set up and align properly.

There are three basic quality levels of pinion gears: Click on Series Numbers for PDF catalog pages.

Pinion Type: Tooth
Helical: Straight:
Soft DIN 8
(~AGMA 10)
Light Loads
Medium Accuracy
21 Series 21 Series
06-Series (Stainless)
Cast Iron & Plastic
DIN 10 Heavy Loads
Low Accuracy
21 Series 21 Series
Hardened &
ISO Flanged
Heavy Loads
Ultra-High Accuracy
78 Series 78 Series
79 Series ---
Blank Bores
Heavy Loads
High Accuracy
24.99 Series 24.98 Series
DIN 7 24 Series 24 Series

* Induction-Hardened pinions are made from soft pinions.

For most rack and pinion applications, a hardened & ground pinion is typically used since it sees the most cycles.  The pinion is usually harder than the rack for this reason.

Click on the "Series" number in left column to view associated PDF catalog page.

Series Style Pinion Description Modules Available Tooth Heat
06 Straight Soft, Stainless 1, 1.5, 2, 3 None ~AGMA 10
07 Straight Soft 5 & 10 mm
Circular Pitch
Optional ~AGMA 10
20 Straight &
Hardened & Ground
Pinion Shafts
2, 3, 4, 5, 6 Case-Hardened ~AGMA 12
21 Straight Soft 1, 1.5, 2, 2.5, 3, 4, 5, 6, 8 Optional ~AGMA 10
21 Helical Soft 2, 3, 4, 5, 6, 8 Optional ~AGMA 10
22 Straight Plastic 1, 1.5, 2, 2.5, 3 None ~AGMA 9
23 Straight Cast Iron 1.5, 2, 2.5, 3, 4, 5, 6 None ~AGMA 10
24 Straight Hardened &
2, 3, 4, 5, 6 Case-Hardened ~AGMA 11
24.98 Straight Hardened &
Ground with Blank Bores
2, 3, 4, 5 Case-Hardened DIN 6
24 Helical Hardened &
2, 3, 4, 5, 6, 8 Case-Hardened ~AGMA 11
24.99 Helical Hardened &
Ground with Blank Bores
2, 3, 4, 5, 6, 8 Case-Hardened DIN 6
24.0 Straight Hardened &
5, 10 & 13.33 mm
Circular Pitch
Case-Hardened ~AGMA 11
74 Helical Hardened & Ground
2, 3, 4, 5, 6, 8 Case-Hardened ~AGMA 11
78 Helical ISO 9409-1-A Flanged 2, 3, 4, 5 Case-Hardened DIN 5
78h Helical TR ISO 9409-1-A Flanged 2, 3, 4, 5, 6, 8 Case-Hardened DIN 5
78s Straight TR ISO 9409-1-A Flanged 2, 3, 4, 5, 6, 8 Case-Hardened DIN 5
79 Helical DIN 5480 Splined Bore 2, 3, 4 Case-Hardened ~AGMA 12
80 Compression Couplings

Automatic Lubrication SystemsWith open gearing such as rack & pinions, lubrication is critical!  A thin film of grease or oil should always be on the contacting tooth flanks to ensure there is no metal-to-metal contact, which can damage the teeth.

It is recommended to use our Automatic Lubrication System, which pumps grease through a felt gear applicator and meshes directly to the pinion or the rack.  This provides continuous lubrication at the tooth flanks, extending the lifetime and maintaining the quality of the gearing.

For more information on our Automatic Lubrication Systems, please follow this link.