Products Home / Actuators, Adjusters, & Transducers / Adjustment Screws / Fine Adjustment Screws, M4 x 0.25 FineFine Adjustment Screws, M4 x 0.25 Fine
- Hex Adjusters, Side Hole Adjusters, and Adjusters with Knobs
- Exceed Class 3 Tolerances
- 250 µm Travel per Revolution
LN4M29
N250L4P
F4MSSN1P
F4MSSK1L
F4MSS25
F4MST12
M4AS15
F4MSSK1
2.0 mm (5/64")
Hex Socket
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| Selection Guide for Adjustment Screws |
|---|
| Imperial |
| 6-80 |
| 6-120 |
| 3/16"-100 |
| 3/16"-120 |
| 1/4"-80 |
| 1/4"-100 |
| 1/4"-100 Matched Adjuster/Bushing Pair |
| 1/4"-170 Matched Adjuster/Bushing Pair |
| 3/8"-100 |
| Metric |
| M2 x 0.20 |
| M2.5 x 0.20 |
| M3 x 0.20 |
| M3 x 0.25 |
| M4 x 0.25 |
| M6 x 0.25 |
| Differential Adjuster Screws |
Features
- M4 x 0.24 Fine Adjuster Screws
- Integrated Adjustment Options:
- 2.0 mm (5/64") Hex Socket
- 1.4 mm (0.06") Side-Located Through Holes
- Knob
- Removable Adjustment Knobs Available for Hex Adjusters
- Threaded Bushings, Adjuster Nuts, and Lock Nuts for Threading Integration
These M4 x 0.25 adjuster screws, which are made from DFARS-compliant materials, are ideal for limited space applications that require fine (250 μm/rev) resolution. Each threaded component is individually tested with a master gauge set that ensures the interchangeability of our fine adjustment components, and all come lubricated to ensure smooth mating into compatible components..
The adjuster body is constructed of 303 stainless steel, and the ball tip is fabricated from 440 stainless steel that is fixed onto the adjuster using epoxy. These adjusters are available with a 2.0 mm (5/64") hex socket for ease of adjustment, a square head equipped with four 1.3 mm (0.05") through holes for applications where side actuation is beneficial, or a knob equipped with an access bore enabling hex adjustment.
M4 x 0.25 threaded bushings, adjuster nuts, and lock nuts, all fabricated from 510 Phosphor Bronze and vacuum-compatible down to 1 x 10-6 Torr, are also available.
For applications where the material certifications are needed, please contact Tech Support prior to purchase.
Integrating Fine Adjustment Screws Into Optomechanical Systems
The assembly process begins by producing the appropriately sized mating hole for the threaded bushing. Given the close fit between the threaded bushing and the mating adjuster screw, we caution against using a press fit to assemble these products. For our own production needs, we use a permanent anaerobic adhesive that provides excellent long-term performance.
We recommend using Loctite Anaerobic Adhesive product number 680 or equivalent. In order to ensure maximum strength between the bonded parts, we strongly urge the user to follow carefully the instructions provided by Loctite, which specify the amount of clearance between the threaded bushing and the mounting plate. The most common source of failure is not allowing for the proper clearance between the parts being bonded since this clearance provides for the proper volume of adhesive.
When assembling, apply a small amount of the Loctite adhesive to the threaded bushing only. Rotate the bushing as it is installed to ensure a uniform distribution of the adhesive. After insertion, remove any excess adhesive from around the part.
As shown in the figure to the right, the flange on the mating bushing is designed to support the axial load of the screw and bushing assembly.
Drilling and Tapping
While we recommend using our fine adjusters with the appropriately matched threaded bushing (sold below), it is also possible to incorporate them directly into a part or material by creating a threaded hole. For the adjusters on this page, the diameter of the pilot bore should be 3.77 mm ± 0.037 mm. The corresponding metric drill bit size is 3.75 mm (0.1476") and the corresponding imperial drill bit is size #26 (0.1470"). The hole can then be tapped with TAPM4025. For fine pitch threads, it is especially important to tightly tolerance the pilot bore because of the shallow thread depth. For more information, see our taps and drill bit kit page.
OEM & Custom Precision Screws
Thorlabs manufactures custom and high volume OEM precision screws and bushings with various diameters, lengths, and threads. To inquire about custom or OEM precision screws, please contact Technical Support or use the "Contact Us" form to the right. A specialist will contact you within 24 hours or the next business day.
Precision Screw Capabilities
Thorlabs' in-house machine shop, located in Newton, NJ, gives us the ability to quickly produce large quantities of precision screws and bushings. We are equipped to manufacture screw diameters ranging from 2 mm to 20 mm with lengths up to 165 mm and a maximum thread pitch of 200 TPI. Our standard adjuster screw design has a hardened steel ball tip to provide a single point of contact; for other applications we are able to provide adjusters without the steel ball. Custom orders can be achieved on a case-by-case basis. For large orders of an item, Thorlabs passes on to the customer the cost savings associated with planned production of high volumes of that item. For more information on Thorlabs' discount pricing policy, click the "V" link to the right. We also offer a large variety of stock precision screws, which are available here.
Fast Turn-Around Times
Our experienced, highly skilled machinists are running our on-site Citizen Swiss Screw Machines 24 hours a day, allowing us to produce high-volume custom and OEM orders. Each machine is capable of running unattended, producing one screw every 30 to 120 seconds. This flexibility allows us to fulfill multiple orders at once without sacrificing quality.
High Quality
Thorlabs inspects all of our fabricated precision screws and bushings after the initial fabrication process and right before packaging. All inspections adhere to the ANSI AQL1.5 acceptable quality level, which states that if a certain percentage, based upon the amount of product in a certain lot, does not meet specification, then the entire lot is not sold. This ensures that all customers receive the highest quality product every time and that all items will be of equal performance.
Precision Screw Production
| Posted Comments: | |
Jorge Rosano
(posted 2023-06-20 13:40:45.413) Hi,
I have a couple questions about the ball:
1. Does it rotate?
2. Does it use a spring?
3. How much can the distance between the ball tip and the end of the thread change? We would need as little game as possible betwen the ball itp and the thread for our application.
Kind Regards,
Jorge Rosano cdolbashian
(posted 2023-06-22 04:05:41.0) Thank you for reaching out to us with these inquiries. The ball is epoxied into the tip of the actuator, so we expect little to no motion/movement of the ball tip with respect to the threaded actuator. Yossi Birman
(posted 2022-03-29 22:44:03.017) Hi,
I'm Yosef Birman. a Mechanical engineer for Lumenis Ltd.
I intend to implement Thorlabs fine adjustment screws into my design.
In order to define the proper tapped hole in the accommodating parts, may I ask to get the tapping hole chart for the entire size range of fine adjustment screws? Typical required info is: Thread major and minor diameters, Tap drill, etc.
Thanks in advance.
Yosef Birman jdelia
(posted 2022-04-04 08:20:48.0) Thank you for contacting Thorlabs. I have contacted you directly about this, however most of this information can be found on our taps product family page: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=1189. Peter Kerkhof
(posted 2021-01-20 05:48:22.91) Hello,
What are the possibilities of getting a F4MSS or F3MSS Fine Hex Adjuster with following tip options:
1) Without a ball, but with a flat end?
2) With a ball but with a flat cut on the ball end?
Best regards,
Peter Kerkhof YLohia
(posted 2021-01-20 02:38:20.0) Hello, thank you for contacting Thorlabs. Custom optics can be requested by contacting your local Thorlabs Tech Support team (in your case, europe@thorlabs.com). We discuss the possibility of offering this directly. |
Zoom
- Six Lengths Available from 8 mm to 25 mm
- 2.0 mm (5/64") Hex Key Available
- Max Load: 8.5 kg (18.74 lbs)
- Material: DFARS-Certified Stainless Steel
- Traceable Material Certification Available (Must be Requested at Time of Purchase)
Our high precision M4 x 0.25 Fine Hex Adjusters can be adjusted with a 2.0 mm (5/64") hex key or with our F4MSSK1 or F4MSSK1L removable adjustment knobs, available below.
Drilling and Tapping
While we recommend using our fine adjusters with the appropriately matched threaded bushing (sold below), it is also possible to incorporate them directly into a part or material by creating a threaded hole. For the adjusters on this page, the diameter of the pilot bore should be 3.77 mm ± 0.037 mm. The corresponding metric drill bit size is 3.75 mm (0.1476") and the corresponding imperial drill bit is size #26 (0.1470"). The hole can then be tapped with TAPM4025. For fine pitch threads, it is especially important to tightly tolerance the pilot bore because of the shallow thread depth. For more information, see our taps and drill bit kit page.
Zoom
- Six Lengths Available from 8 mm to 25 mm
- 2.5 mm Square Head with Four 1.4 mm (0.06") Side-Located Through Holes
- Max Load: 8.5 kg (18.74 lbs)
- Material: DFARS-Certified Stainless Steel
- Traceable Material Certification Available (Must be Requested at Time of Purchase)
These high precision M4 x 0.25 Fine Hex Adjusters feature a 2.5 mm square head equipped with four 1.4 mm (0.06") through holes. The through holes are are sized to accommodate a 1.3 mm (0.05") hex key or balldriver, thereby enabling side actuation. Please note that these adjusters are not compatible with the removable adjuster knobs sold below.
Drilling and Tapping
While we recommend using our fine adjusters with the appropriately matched threaded bushing (sold below), it is also possible to incorporate them directly into a part or material by creating a threaded hole. For the adjusters on this page, the diameter of the pilot bore should be 3.77 mm ± 0.037 mm. The corresponding metric drill bit size is 3.75 mm (0.1476") and the corresponding imperial drill bit is size #26 (0.1470"). The hole can then be tapped with TAPM4025. For fine pitch threads, it is especially important to tightly tolerance the pilot bore because of the shallow thread depth. For more information, see our taps and drill bit kit page.
Zoom- 15 mm and 20 mm Long Adjusters Available
- Max Load: 8.5 kg (18.74 lbs)
Zoom- Use with M4 x 0.25 Hex Adjusters
- Clearance Hole Allows Access to Adjuster's Hex Socket
- Available in 2 Sizes
- Knurled Knob Increases Adjustment Sensitivity
The F4MSSK1 and F4MSSK1L Removable Adjustment Knobs thread onto our M4 x 0.25 F4MSS series hex adjusters to allow adjustment without the use of a hex key. This provides quick and easy adjustments for a broad range of applications. The adjuster knobs are available in two sizes: Ø14.7 mm and Ø7.1 mm.
Zoom- Ideal for Slip Fit Applications
- Material: 510 Phosphor Bronze
- Vacuum Compatible: 10-6 Torr
- Recommended Bore Diameter: 0.2165" +0.0005/-0.0000"
Our M4 x 0.25 threaded bushings are commonly used in slip fit applications where fine adjusters are needed. Due to the tolerances of our fine adjusters, we discourage press fitting these bushings. The recommended bore diameter for our M4 x 0.25 bushings is 0.2165" +0.0005/-0.0000". Please see the Integration tab for more information. For vacuum applications, we recommend a thorough ultrasonic cleaning to remove any grease or particulates prior to use.
Zoom- Externally M6 x 0.5 Threaded
- Material: 510 Phosphor Bronze
- Vacuum Compatible: 10-6 Torr
Our N250L4P vacuum-compatible fine adjuster nut is internally M4 x 0.25 threaded and externally M6 x 0.5 threaded. These sleeves can be threaded into M6 x 0.5 tapped holes to provide M4 x 0.25 fine adjustment in a variety of applications where threaded bushings are not suitable. For vacuum applications, we recommend a thorough ultrasonic cleaning to remove any grease or particulates prior to use.
Zoom- Knurled Outside Diameter for Easy Tightening
- Material: 510 Phosphor Bronze
- Vacuum Compatible: 10-6 Torr
The LN4M29 lock nut features a knurled outside diameter to make gripping the nut easier when loosening or tightening. The lock nut is made from 510 Phosphor Bronze, which is vacuum rated for 10-6 Torr. Each nut features blind holes that allow a 2.0 mm (5/64") hex key to be used to help tighten the lock nut.
M4 x 0.25 Adjustment Screws