Trackballs are ideal for applications that require the precise positioning of a cursor on a display screen. Daco trackballs are extremely robust and are designed to provide an exceptionally smooth, free and linear action.

We have designed our trackballs to deliver the highest performance under the most difficult conditions. In many trackballs the encoder shafts used to sense rotation are also used to support the ball. This design leaves the device vulnerable to damage because any shock applied to the ball is transmitted to the encoders.

The use of inflexible suspension points means that, if the trackball is mounted at an angle or is subjected to vibration, the contact between ball and encoder can be broken, thereby stopping meaningful electrical output. And as the ball can never rotate in the direction of both encoder shafts simultaneously, there is a bias in the ball’s rotation that prevents it from operating smoothly.

Daco trackballs feature separate support and encoder shafts, optimising function and usability.

Ball rotation is sensed by two high-quality optical encoders that, in our modular designs, contact the ball via a soft polyurethane foam roller chosen for its resistance to compression set, flame and corrosion. The foam’s flexibility allows it to "ride over" any small particulate contamination, which can cause jamming on other trackball encoders. This also ensures that contact between the ball and the encoders is maintained even if the trackball is mounted at an angle or is subjected to heavy vibration.

We have engineered the encoders specifically for demanding applications. They have very low friction and inertia, which means there is minimum effect on the "feel" of the trackball's operation.The ball itself is supported by six stainless steel ball bearings – within a polymer bearing – that are free to rotate in any direction. This means that there is never a bias in the direction of operation. Any excessive force applied to the ball is transmitted through the lower polymer bearing into the robust housing holding it, thereby avoiding damage to the encoders.

The result is a highly-reliable and cost-effective design.

Characteristics / Options

Daco's modular trackballs are available in two versions – the MT4 and the MT6. The MT4 is higher specification and is therefore the more popular choice for more demanding environments. The MT6 is commonly used for less extreme applications.

Both series feature MT4 trackballs also feature
High reliability Anodised main structure to give extra corrosion resistance
Very smooth action Fully floating drip seal
Quiet operation High-temperature components on interface circuit boards
Extreme robustness Operating temperature range extended to -40°C to +70°C
Low start-up and operating force Aluminium top flange to reduce products of combustion
Operating force unaffected by direction of rotation Warranty extension to three years
Operation at any angle of mounting Wire with dual-wall insulation combining radiated polyalkene and radiated polyvinylidene fluoride – this wire has low toxicity products of combustion and meets a wide range of specifications including MIL W 81004 and DEF STAN 61-12 part 18
Operation even under heavy vibration  
Ball – and hence cursor – direction remains linear even when spun to make large movements (does not exhibit a curving response)  
Minimum two-year warranty  
Engineered under an ISO 9001 / AS9100-approved quality system  

Each trackball model features a range of options including different ball sizes, control buttons and interfaces, so get in touch to discuss a configuration that meets your requirements.

Modular Options Available  
Trackball Series MP4
Ball Size 1.5 Inches
2.0 Inches
3.0 Inches
Ball Colour Black
Mounting Detail Plate with 0 switches
Plate with 1 switch
Plate with 2 switches
Plate with 3 switches
Plate with 1 ergo switch
Plate with 2 ergo switches
Plate with 3 ergo switches
No plate, threacled holes in flange
No plate, through holes in flange


None (flying leads)
None (9 way D connector)*
RS232 (Mouse Systems)
RS422 (Mouse Systems)
RS232 (Mircosoft)**

*The 9-way D connector is mounted in place of an interface circuit board.

**The RS232 (Microsoft) interface can only encode 2 switches.


Excitation Voltage 5 ± 0.5 VDC
Current 150 mA + output current
Output voltage, per encoder TTL compatible true square wave on output A (yellow) and B (orange).
High 2.7V min.
Low 0.8V max.
Output current, per encoder 18 mA max sink; Fan out of 10 TTL
Insulation, per encoder >10M ohms at 500V
Direction sensing + X XB leads XA by 90 ± 30°
+ Y YA leads YB by 90 ± 30°
Typical Resolution 1.5 inch ball 150 pulses per ball revolution
2.0 inch ball 200 pulses per ball revolution
2.5 inch ball 250 pulses per ball revolution
3.0 inch ball 300 pulses per ball revolution
Storage temperature MT4 series -60°C to +90°C
MT6 series -10°C to +55°C
Operating temperature MT4 series -40°C to +70°C
MT6 series 0°C to +50°C
Humidity MT4 series Up to 100% non-condensing
MT6 series Up to 95% non-condensing
MTBF Trackball only 100,000 hours 2 million ball revolutions
Assumes a level of routine maintenance



If you would like a quote for a modular trackball and know your basic requirements please use the form below, referencing the dimensions drawings and list of options. We are delighted to assist you with the spec for your device, so please don’t hesitate to get in touch for advice on the best configuration for your application.

Dimensioning Diagrams

Diagram 1

Diagram 2

Diagram 3

All dimensions are in mm and are given as maximums, unless otherwise stated.
Dimensions in RED are absolutes with positional tolerances as indicated.
Mounting Option OP4 is the threaded hole size.
Mounting Option OP5 is the through hole size.
Column PCD refers to the Mounting Hole PCD.

ITEM Trackball Dimensions Plate Dimensions
Diameter Dimension Mounting Option PCD Dimensions
MT A B C 1 2 3 OP4 OP5   4 5 6 7 8 9 10
4/15 110 75.2 43.1 8.7 5.3 34 M3   63.0 145.2 133.0 69.0 130.2 118.0 59.0 10.0
6/15 110 72.2 43.1 8.6 5.3 34 M3   63.0
4/20 123 88.2 55.9 12 6.5 38 M3   76.2
6/20 123 83.5 55.9 15.4 3.05 38 M3   76.2
4/25 135 106.2 70.3 18 5.4 42.4 M3   94.0 182.2 170.0 88.0 160.2 148.0 74.0 13.0
6/25 135 106.2 70.3 20 5.4 42.4 M3   94.0
4/30 152 118.2 84.0 23 6.1 50 M3   110.0
6/30 152 118.2 84.0 23 6.1 50 M3   110.0

All dimensions are in millimetres and are given as maximums unless otherwise stated.
Dimensions in red are absolutes with positional tolerances as indicated.
Mounting option OP4 is the threaded hole size.
Mounting option OP5 is the through hole size.
PCD refers to the mounting hole PCD.