Baader 2" Diamond Steeltrack Crayford Focuser for Refractors # BDS-RT 2957210

A. Introducing Baader Diamond Steeltrack Premium Focusers

In recent years, the Crayford style of ball-bearing guided focuser has become popular due to its smooth motions, absence of pinion backlash, and rigid drawtube support. Baader's new Diamond Steeltrack Premium Focusers incorporate a number of innovative features that further enhance the smoothness and robustness of the Crayford focuser.

Baader's innovative diamond-geared drive system delivers the smooth totally backlash-free action of a friction drive with the positive non-slip high load capacity of a rack and pinion. Additional improvements in the bearing-guide system help to take the Baader Diamond Steeltracks (BDS) far enough beyond all other crayford-type focusers that some have called them 'Baaderford'.

B. 2" Refractor Diamond Steeltrack Focuser: Baader part # BDS-RT or 2957210

Baader Planetarium's 2" Refractor Diamond Steeltrack Focuser gives refractors a full 3" (76mm) of velvety smooth focusing travel. Easily adaptable to popular refractors.

• Overall length fully retracted 80mm (backfocus length).
• Drawtube is fully internally baffled and blackened to eliminate off-axis stray light.
• 72mm dovetail receiver permits 360-degree rotation of focuser with single-screw locking.
• Optional RT adapterset permits easy attachment to Celestron/Skywatcher/Zeiss refractors, and is adaptable to other refractors.
• Optional adapters available to fit a variety of other refractors.
• Weighs 2lb-6oz (1077g).

C. General Specifications for all Baader Diamond Steeltracks

Baader Diamond Steeltrack (BDS) Focusers have the following specifications:

Drive System

• True diamonds form a micro-geared high precision drive system never accomplished before.
• In comparison to conventional crayford or rack & pinion drives, this micro-geared movement has zero backlash, zero cogging, and zero flexure.
• Diamond Steeltrack 2" focusers lift a payload of 6kg (13 lbs) straight up, without slipping, without excessive bearing preload (bearing preload can be increased further if necessary).
• Bearing system utilizes unbreakable instrument grade roller-bearings instead of simpler ball bearings - handles higher loads with greater rigidity and accuracy. No Teflon-pads anywhere.
• 1:11 stainless steel fine-focus mechanism, ready for attachment of the optional Steeldrive temperature-compensating motor drive system. The brass reduction gear is prepared to accept the timing belt of the Steeldrive motor-drive unit. The outer case of all Diamond Steeltracks have a dovetail cut into the driving-axis housing to accommodate the motor block of the Steeldrive unit.
• Detachable drive block assembly is reversible for right hand or left hand fine-focus operation and for attaching the Steeldrive motorblock onto Diamond-NT-Steeltracks for newtonian telescopes.
• Shortest possible mechanical design achieves optimum balance between focuser height (backfocus) and rigidity requirements.
• Zero shift locking knob to precisely stop any movement without affecting optical axis adjustment.

Focusing Drawtube

• Each bearing individually adjustable for precise alignment of mechanical vs. optical axis.
• Ultra-hard subzero coated bearing races – precision milled and much harder than anodizing or stainless steel.
• Oversized 55mm inner clear diameter, to prevent vignetting, with anti-reflection knife-edge baffles.
• 85mm focus travel.

Clamping System

• S58 Dovetail ring-clamp built into focusing tube for accepting optional T-2 / M48 / M68 and other S58 direct-thread adapters to enable direct thread connection of accessories and cameras without 2" clamp.
• 2" eyepiece clamp with hardened bronze clamp ring (length of clamp: 12.5mm (0.5") included as standard.
• Optionally available: 2" Baader Clicklock-clamp with integrated S58 dovetail (added length: 16mm (5/8")).