Rail Platform Positioners for 34 mm Rails

  • Fine Adjustment of Platforms Along the Rail Axis
  • Up to 0.45" (11.43 mm) of Translation in One Direction


Rail Platform Positioner


Rail Platform Return Positioner

Application Idea

Fine Tuning a
Lens Position

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  • XT34N Positioner:
    • M2.5 x 0.2 Adjuster Screw Pushes Clamping Platform or Rail Carriage Along the Rail Axis
    • 0.0079" (200 µm) of Translation per Revolution
    • Max Translation Range of 0.45" (11.43 mm)
    • Adjuster Screw Accepts 1.5 mm Hex Driver
  • XT34N1 Return Positioner:
    • Spring-Loaded Plunger that Clamps onto 34 mm Rails
    • Use with XT34N Positioner for Bidirectional Adjustment

Thorlabs' XT34N and XT34N1 Rail Platform Positioners are designed to aid in fine alignment of optics mounted on a 34 mm rail platform. The XT34N positioner consists of a M2.5 x 0.2 adjuster screw that is incorporated into a 34 mm rail clamp. The screw provides smaller, smoother movement than coarse translation by hand. One revolution of the screw will result in a translation of 0.0079" (200 µm), and the included F2D5ES20 M2.5 x 0.2 adjuster screw can travel 0.45" (11.43 mm), measured from the front surface of the clamp; longer adjuster screws can be installed if desired.

The XT34N1 rail return positioner provides passive adjustment when used in conjunction with the XT34N positioner. When a platform is placed between the platform positioners, retracting the adjustment screw on the XT34N positioner allows the spring-loaded plunger on the XT34N1 return positioner to push the carriage back a maximum of 0.195" (4.95 mm). Additionally, the return positioner provides stability while making adjustments. The compression spring tension can also be adjusted with a 5/64" (2.0 mm) hex key.

To use, place the positioners on the rail so the ball of the adjuster screw and the tip of the plunger come into contact with the clamping platform or rail carriage to be positioned, noting that this platform will move in the direction away from the XT34N positioner. Then tighten down the positioners using a 1.5 mm hex driver. Once both the positioners are secured, loosen the clamp holding the platform or carriage to the rail, then turn the adjuster screw with a 1.5 mm hex driver to push the platform until the desired amount of translation is achieved.

We do not recommend using these positioners with assemblies that use our XT34C1 or XT34C2 Double Dovetail Clamps to attach to the rail. Since it is necessary to loosen the clamp to translate the assembly, any optomechanics held by the clamp will also be loose, potentially leading to unintended movements.

Thorlabs offers a wide and growing complement of accessories for 34 mm rails, including clamps and angle brackets, breadboard mounts, rail carriers, mounting platforms, lens tube adapters, and rail joiners. Together with size adapters that incorporate 66 mm and 95 mm rails into an XT34 setup, these tools provide a complete family of rigid, versatile building blocks suited for virtually any optomechanical setup.

XT34 34 mm Optical Rail Accessories
Rails Rail Positioners Angle Clamps and Brackets Breadboard Mounting Size Adapters Rail Joiners Rail Carriers Mounting Platforms Lens Tube Adapter
Rails Rail Platform Positioners Clamps and
Angle Brackets
Size Adapters Rail Joiners Rail Carriers Mounting
Lens Tube

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Rail Platform Positioners for 34 mm Rails

Based on your currency / country selection, your order will ship from Newton, New Jersey  
+1 Qty Docs Part Number - Universal Price Available
XT34N Support Documentation
XT34NCustomer Inspired! Rail Platform Positioner for 34 mm Rails
XT34N1 Support Documentation
XT34N1Customer Inspired! Rail Platform Return Positioner for 34 mm Rails