Baader Steeldrive II Motor Focuser w/ Controller

Backlash-Free Drive: A Timing Belt System for 8 kg Payloads

The core of the Steeldrive II is a high-torque stepper motor that connects to your focuser's fine-adjustment knob via a toothed timing belt. This direct-drive design completely eliminates the backlash and potential failure points associated with gearbox-driven motors. It ensures every command from the controller results in precise, repeatable movement, capable of quickly and accurately positioning imaging trains weighing up to 8 kg.

Standalone Intelligence: 3 Manual Focusing Modes

Unlike focus motors where the electronics are integrated into the motor housing, the Steeldrive II's "brain" resides in a separate, dedicated hand controller. This allows for complete computer-free operation in the field, with three distinct manual modes for vibration-free focusing at the telescope.

• Normal Mode: The focuser moves as long as a key is held down.
• Jogging Mode: Each key press moves the focuser a user-defined distance (e.g., 0.1 mm), configured in the SteelGo software.
• Single Step Mode: A single key press initiates the smallest possible movement of approximately 2.5 micrometers for critical final adjustments.

Absolute Positioning with a 2.5µm Resolution

The Steeldrive II achieves repeatable, absolute positioning through a contactless, wear-free hall-effect homing sensor. When paired with a small magnet on the focuser's drawtube, it enables the system to return to saved positions with 2.5µm accuracy. Even without the sensor, the controller stores the focuser's absolute position in a persistent EEPROM buffer, which is reloaded on startup unless the focuser was moved manually while powered off.

Dual-Sensor Temperature Compensation and 10W Dew Control

This system offers a sophisticated solution for managing thermal focus shift and dew. You can connect two digital temperature sensors simultaneously—one to the motor and one to the controller—to measure different points on your telescope. The controller can use a single sensor or the average of both to automatically compensate for temperature changes, a feature that can run standalone after initial setup.

Furthermore, the controller includes a 12V/1A power output, capable of driving a dew heater up to 10W. You can program a target temperature, and the Steeldrive II will intelligently manage the heater to keep optics just above the dew point, preventing moisture without introducing excess heat.

German Engineering: SteelGo Software and 0.7W Power Draw

All mechanical components are CNC-milled from aluminum, and the electronics are designed, manufactured, and coated in Germany for durability. The companion SteelGo software provides a comprehensive interface for calculating temperature compensation factors and configuring all system parameters. When idle, the motor current is automatically reduced, allowing the Steeldrive II to hold its position while consuming only about 0.7 W of power.