Mounting Platforms for 66 mm Rails
- Dovetail Platforms with 1/4"-20 (M6) Holes and Slots
- Mount Standard Optomechanics to 66 mm Rails
- Clamps are Positioned by Sliding Along Rail
Optical Axis
Centered Over
Rail Axis
XT66C5
Blank Clamping
Platform
XT66C4
Clamping Platform with
Counterbored Slot
XT66D3
X-Axis Slotted Dovetail
XT66D2-50
Dovetail with
Counterbored Holes
Please Wait
Click to Enlarge
Rail-Mounted Periscope
(See Application Idea Tab for Details)
Features
- Compact Platforms Provide Compatibility with Standard 1/4"-20 (M6) Optomechanics
- Conveniently Insert and Remove Mounts from an Optical Path
- Options with Tapped Holes, Counterbored Holes, or Counterbored Slots
- Some Models Contain Built-In Clamp for Direct Compatibility with Rails
- Blank Clamping Platform for Custom Applications
Thorlabs provides a wide selection of platforms that permit optomechanics with standard 1/4"-20 (M6) threadings to be incorporated into a 66 mm rail assembly.
Mounting Platforms and Dovetails
Our mounting platforms feature 1/4"-20 (M6 x 1.0) tapped holes or 1/4" (M6) counterbored holes, while the dovetails have 1/4" (M6) counterbored slots or a single 1/4"-20 (M6 x 1.0) tapped hole. They attach to the rail with any of our Dovetail Clamps and are available in several different geometries, as illustrated below.
In order to maintain a minimal physical profile, our XT66D2 and XT66D3 Slotted Dovetails require our reduced-height Low-Profile Channel Screws or Low-Profile T-Nuts to fasten to standard optomechanics. The counterbores in these platforms are too shallow to accommodate standard 1/4"-20 or M6 cap screws.
Mounting Clamps
Our mounting clamps feature a built-in dovetail clamp that provides direct compatibility with 66 mm rail systems. The XT66C4 Clamping Platform contains a 1/4" (M6) counterbored slot that is parallel to the rail axis, while the XT66RC Counterbored Pivot Platform includes a 1/4" (M6) counterbored slot that can be rotated through a full 360°. We also offer the XT66C5 Blank Clamping Platform for customers who wish to machine custom mounting options.
Thorlabs offers an extensive selection of accessories for 66 mm rails, including clamps and angle brackets, breadboard mounts, mounting platforms, rail carriages, rail platform positioners, rotation slide platforms, rail joiners, and lens tube adapters. Together with size adapters that incorporate 34 mm and 95 mm rails into an XT66 setup, these tools provide a complete family of rigid, versatile building blocks suited for virtually any optomechanical setup.
XT66 66 mm Optical Rail Accessories | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Rails | Clamps and Angle Brackets |
Mounting Platforms |
Rail Platform Positioners |
Rail Carriage | Breadboard Mounting |
Rotation Slide Platform |
Cage System Mounts |
Lens Tube Adapter |
Rail Joiner | Size Adapters |
Application Idea: A Simple Periscope
The photographs to the left depict a simple periscope constructed using our 66 mm rail system. The two photos display the same setup from two different angles in order to clearly show how each part has been integrated. The labeled parts correspond to a row in the upper table, while the lower table shows the clamps and optical mounts used throughout the periscope.
Please note that lenses and mirrors, which are not shown in the tables below, would also be required.
Label | Item # | Description | Product Image |
---|---|---|---|
1 | XT66-500 | 66 mm Construction Rail, L = 500 mm | |
2 | XT66D2 | 50 mm Long Slotted Dovetail with One Z-Axis Counterbored Slot | |
3 | XT66D2-50 | 50 mm Long XT66 Platform with Three 1/4"-20 (M6) Counterbores | |
4 | XT66RA2 | Right-Angle Clamp for 66 mm Rails | |
5 | XT66DP-500 | 66 mm Double Dovetail Rail, L = 500 mm | |
6 | XT66DE1 | 20 mm Long, 1/4"-20 Tapped Dovetail for 66 mm Rails | |
Additional Items | |||
XT66C1 | 20 mm Long Double Dovetail Clamp for 66 mm Rails | ||
XT66C2 | 40 mm Long Double Dovetail Clamp for 66 mm Rails | ||
MA45-2 | 45° Mounting Adapter, Compatible with KM100 and KM200 | ||
KM100 | Ø1" Kinematic Mirror Mount | ||
LMR1 | Ø1" Lens Mount |
Posted Comments: | |
user
 (posted 2021-08-06 14:01:07.463) We recently received a shipment of ~50 XT66C4 clamps and the individual perforated bag are emitting an incredibly strong odor. Is there any anticorrosive or preservative applied to the component or packaging? YLohia
 (posted 2021-08-06 04:59:54.0) Hello, thank you for contacting Thorlabs. We're sorry to hear about the issues you're experiencing with these parts. The XT66C4 is anodized-- we just don’t color it black, so it goes through all the same process as the rest of our optomech parts. The only difference in the process is that the acid etch gives the part a satin finish. After the acid etch, the parts go through a number of rinse tanks, a deoxidation, a couple more rinse tanks, then anodizing and some more rinse tanks. There should be no smell. I have reached out to you directly to obtain more information. Emilio Graff
 (posted 2020-10-08 10:09:02.08) The XT66C5 blank platform is great for mounting custom stuff (e.g. cameras). In my client's current application, that's exactly what they wanted, except the camera was too long. So I used your CAD (you have inspired so many custom designs in my career - you have no idea) to make a longer version of XT66C5 that could allow for mounting the camera with all four screws.
Except now I have to buy XT66C5's just for the small clamping piece, screws, and washers. As you can imagine, that's still cheaper than making my own (even at quantities of ~20, like my last order).
So I would love it if you sold just the clamping piece with screws and hardware. Or maybe even allow buying both "halves" of XT66C5 separately. I would handily pay $20 for the clamping piece; my main concern now is that I'm going to have 20 chunks of aluminum and no use for them.
Thank you, and thank you, for over a decade of enabling designs - either with your parts or the Frankensteins I've created off your CAD models. llamb
 (posted 2020-10-14 02:39:44.0) Thank you for your feedback! We will take your suggestion into consideration for a potential catalog offering. For the meantime, I have reached out to you directly to discuss a quote for the XT66C5's component pieces on their own. user
 (posted 2017-09-15 10:07:03.883) Is there any possibility to make a Platform like XT66C5 Blank Clamping Platform with two/three M6 threaded holes (distance 25mm/12.5 mm)? tfrisch
 (posted 2017-09-26 03:03:12.0) Hello, thank you for contacting Thorlabs. You may be able to use XT66C4 (slotted clamping platform) with XE25T3/M (low profile M6 nut), but if you would like to pursue a custom M6 threaded platform, please reach out to us at TechSupport@Thorlabs.com |
Click to Enlarge XT66D2-50 Platform Fits Two Post Holders at Once
- Variants with Counterbored or Threaded Holes
- MPR4(/M): Twelve 1/4"-20 (M6 x 1.0) Threaded Holes, 4" (100 mm) Long
- MPR8(/M): Twenty-Four 1/4"-20 (M6 x 1.0) Threaded Holes, 8" (200 mm) Long
- XT66D2-40: One 1/4" (M6) Counterbore, 40 mm Long
- XT66D2-50: Three 1/4" (M6) Counterbores, 50 mm Long
- Fastened to Rail with Dovetail Clamps
- Ideal for Attaching Posts, Post Holders, or Pedestal Posts to a 66 mm Rail
The MPR4(/M) and MPR8(/M) Rail Platforms are 4" (100 mm) or 8" (200 mm) long, respectively, and provide 1/4"-20 (M6 x 1.0) tapped holes at 1" (25.0 mm) spacings. The 66 mm dovetail on the underside of each platform is compatible with 66 mm rail clamps/brackets, mounting platforms, and MPP Series Posts for Rigid Stands. When the platform is extended fully while clamped in the XT66C4 clamp (i.e., both dovetail locking screws can still be engaged), the outermost edge of the platform will support a load of 20 lbs (9 kg).
The XT66D2-40 and XT66D2-50 Mounting Platforms offer one or three 1/4" (M6) mounting counterbores, respectively. The XT66D2-40 platform is 40 mm long to match our XT66C2 Double Dovetail Clamp. In contrast, the 50 mm version (XT66D2-50), pictured at right, allows three components mounted directly on Ø1/2" Posts or two components mounted with Ø1/2" Post Holders to be placed in close proximity. The counterbored holes in these platforms accept standard cap screws.
Click to Enlarge Tapped Dovetails are Ideal Mounts for Single Components
- Includes One 1/4"-20 (M6) Tapped Hole
- Fastened to Rail with Dovetail Clamps
Our Tapped Dovetails hold a single optomechanical component to a 66 mm rail system. As shown to the right, they are perfectly sized to be attached to an XT66 rail by using an XT66C1 Double Dovetail Clamp.
Click to Enlarge
A previous-generation Polaris® Mount on an RS1 Pillar Post, attached to a XT66D2 Slotted Dovetail which is locked by a XT66C2 Double Dovetail Clamp to a 66 mm rail.
- XT66D2: One 1/4" (M6) Counterbored Slot Along Length
- XT66D3: Three 1/4" (M6) Counterbored Slots Across Width
- Fastened to Rail with Dovetail Clamps
- Used with Low-Profile Channel Screws or Low-Profile T-Nuts, Sold Below
These 50 mm long dovetail sections contain one or three counterbored slots that provide flexible mounting options along the X or Z axes. The XT66D2's counterbored slot is parallel to the rail axis, while the XT66D3's three counterbored slots lie across the rail width. The XT66D3 additionally includes two Ø1/8" holes positioned to accept the dowel pins on translation stages like the MT1 Single-Axis Translation Stage.
Since these mounting dovetails have minimal height, their counterbored slots are too shallow to accommodate standard 1/4"-20 or M6 cap screws. We therefore recommend that either Low-Profile Channel Screws or Low-Profile T-Nuts are used instead (see below for details).
Shown above and to the right is a previous-generation Polaris® kinematic mount mounted on a standard 66 mm rail with a pillar post. The pillar post can be coarsely positioned along the counterbored slot before being locked down.
Click to Enlarge Fastens to Base Rail without Additional Clamps
- Contains One 1/4" (M6) Counterbored Slot
- Slides Along Rail Side Prior to Lockdown
- Locking Screws Fasten with 2.5 mm Balldriver or Hex Key
The XT66C4 Clamping Platform contains a single 1/4" (M6) counterbored slot that is parallel to the rail axis and directly fastens to a 66 mm rail using two side-mounted screws that lock with a 2.5 mm balldriver or hex key. The counterbored slot accepts standard cap screws. This clamp is also offered without the counterbored slot (see immediately below) for customers who prefer custom mounting options.
For applications requiring fine translation of the clamping platform, Thorlabs manufactures the XT66N Rail Platform Positioner.
- Blank Platform for Designing Custom Mounting Options
- Slides Along Rail Side Prior to Lockdown
- Locking Screws Fasten with 2.5 mm Balldriver or Hex Key
The XT66C5 Blank Clamping Platform is for customers who would like custom mounting options for a 66 mm rail assembly. It is identical to the XT66C4 Clamping Platform sold immediately above, but contains no 1/4" (M6) counterbored slot. This platform's aluminum construction features a durable, clear anodized coating. The machinable area of the platform, which is shaded in the diagram to the right, is constrained by the width of the bottom relief cut and the threading depth of the two side-mounted locking screws.
For applications requiring fine translation of the clamping platform, Thorlabs manufactures the XT66N Rail Platform Positioner.
Click to Enlarge Counterbored Slot Accepts Standard Optomechanical Parts
- Rounded Dovetail Shape Allows Any Orientation Between Rail and Mounted Component
- Contains One Counterbored Slot Compatible with 1/4"-20 (M6) Low-Profile Channel Screws and Low-Profile T-Nuts
- Locking Screws Fasten with 2.5 mm Balldriver or Hex Key
The XT66RC Counterbored Pivot Platform contains a rotatable counterbored slot that accepts 1/4"-20 (M6) optomechanics. Due to this platform's compact profile, the counterbored slot is too shallow to accommodate standard 1/4"-20 or M6 cap screws. We therefore recommend that either Low-Profile Channel Screws or Low-Profile T-Nuts, sold below, are used instead.
Alternatively, this platform can be used to mount a second rail to a base rail at an arbitrary angle in combination with a Double Dovetail Clamp.
Click to Enlarge
Low-Profile T-Nut in Counterbored Slot
Click to Enlarge
Low-Profile Channel Screw in Counterbored Slot
Click to Enlarge
Standard Cap Screw Protrudes from Counterbored Slot
Our 1/4"-20 (M6 x 1.0) Low-Profile T-Nuts and Low-Profile Channel Screws have a slim profile that permits them to be used in tight spaces. In particular, they are recommended for use with our XT66RC Counterbored Pivot Platform and XT66D2 and XT66D3 Slotted Dovetails, whose counterbore depths are too shallow to accommodate standard cap screws.
Shown to the right are a standard cap screw, a low-profile channel screw, and a low-profile T-nut in an XT66D2 Slotted Dovetail. The short height of the channel screw and T-nut prevents them from interfering with an attached dovetail clamp.
Item # | Threading | Thread Length | Hex | Head Height | Quantity | Material |
---|---|---|---|---|---|---|
SH25LP38 | 1/4"-20 | 0.38" (9.7 mm) | 1/8" | 0.13" (3.2 mm) | 100 | Steel, Black Oxide Finish |
SH25LP63 | 0.63" (15.9 mm) | 50 | ||||
SH6M8LP | M6 x 1.0 | 8 mm (0.31") | 4 mm | 4 mm (0.16") | 50 | |
SH6M10LP | 10 mm (0.39") | 100 | ||||
SH6M16LP | 16 mm (0.63") | 50 |
Click to Enlarge
Assembled View
Click to Enlarge
Exploded View of SD1 Counterbore Adapter Ring with XT66D2-40
- Use an 8-32 (M4) Cap Screw in a 1/4" (M6) Counterbore
- Sold in Packages of 10
- Does Not Provide 8-32 Compatibility for Parts that Use Low-Profile Channel Screws or Low-Profile T-Nuts
The SD1 Adapter Ring allows an 8-32 (M4) cap screw to be used within a 1/4" (M6) counterbore. It is made of stainless steel and enables a wide variety of 8-32 threaded optomechanical components, such as our LMR Fixed Optic Mounts, to be directly mounted on an XT66 mounting platform without a post or post holder, as shown to the right.
Please note that these adapter rings cannot be used with the XT66D2 or XT66D3 Slotted Dovetails or the XT66RC Counterbored Pivot Platform because there is insufficient depth in the counterbore to accommodate both the adapter ring and a cap screw.