SM-RP1 Rotation Mount

Product Description

• 360° continuous rotation mount
• Can mount Ø1-inch optical components with a maximum thickness of 11.5mm.
• 360° dial with 2° indexing; 1° indexing for the zero scale line.
• Scale alignment line on the base plate for precise positioning, with a 5-arcminute vernier scale directly below for fine angle adjustment.
• Rotation locked via set screws.

The SM-RP1 is a lockable continuous rotation mount. Its knurled dial can rotate 360° continuously with 2° indexing. For auxiliary alignment, the zero scale line extends to the outer edge of the SM1 screw hole with 1° indexing precision. Meanwhile, the base plate is engraved with a 5-arcminute vernier scale, facilitating precise repeatable positioning and fine angle adjustment.

Model	SM-RP1
Dimensions	Ø53.2*62.5mm
Scale Indexing	Dial: 360°, 2° indexing; Zero alignment line: 1° indexing; Vernier scale: 5 arcminutes
Central Aperture	SM1 (1.035”-40) internal thread
Thread Type	M4 screw holes
Weight	95.2g
Material	7075 aluminum alloy

 

Technical Description

Optical Knowledge Point: Common Optical Thread Size Standards

This is a thread specific to Thorlabs Inc. (USA) and not a commonly used optical thread. “SM” is the code for sewing machine threads in thread notation, but this American company uses it for internal and external thread connections of optical lenses and sleeves. The thread type is UNS (Unified National Special Thread) with a tolerance class of 2A/2B. A unique feature of this thread is that regardless of the diameter, the pitch is 40 threads per inch (TPI). Specific dimensions are as follows:

Series	Type	Thread (in)	Nominal Diameter (mm)	Minor Diameter (mm)	Pitch Diameter (mm)	Major Diameter (mm)
SM05	Internal	0.535-40	13.59	12.98±0.07	13.24±0.05	＞13.59
SM05	External	0.535-40	13.59	＜12.78	13.10±0.05	13.50±0.05
SM1	Internal	1.535-40	26.29	25.68±0.07	25.95±0.05	＞26.29
SM1	External	1.535-40	26.29	＜25.48	25.79±0.05	26.19±0.06
SM2	Internal	2.535-40	51.69	51.08±0.075	51.35±0.075	＞51.69
SM2	External	2.535-40	51.69	＜50.87	51.18±0.05	51.59±0.05

Product Description

The SM-RP1 is a lockable continuous rotation mount. Its knurled dial can rotate 360° continuously with 2° indexing. For auxiliary alignment, the zero scale line extends to the outer edge of the SM1 screw hole with 1° indexing precision. Meanwhile, the base plate is engraved with a 5-arcminute vernier scale, facilitating precise repeatable positioning and fine angle adjustment. The set screw on the top is tightened with a 2.0mm hex wrench to lock the rotation of the mount.

The central aperture features SM1 (1.035”-40) internal threads, capable of mounting Ø1-inch optical components up to 11.5mm thick and other SM1-threaded components. Optical components are fixed with 2 included CSK3 retaining rings.

The bottom of the mount is equipped with M4 screw holes (6.5mm deep), which can be mounted with rods for free-space setup.

Assembly

Application Example

Engineering Drawing Download

SM-RP1-Engineering Drawing