Tag Archives: clamping shaft collar

China Customized CNC turning machining precision aluminium stainless steel Set Screw Clamping Shaft Collar threaded shaft drawing

Condition: New
Warranty: \
Applicable Industries: Other, Manufacturing Plant, Machinery Repair Shops, Farms etc
Weight (KG): 1
Showroom Location: None
Video outgoing-inspection: \
Machinery Test Report: \
Marketing Type: Ordinary Product
Warranty of core components: \
Core Components: shaft
Structure: Worm
Material: stainless Steel, Stainless Steel
Coatings: \
Torque Capacity: \
Model Number: \
Surface Treatment: Anodizing, Passivation, Plating, Polishing, Oxidation, etc
Size: Customized
Tolerance: +/-0.005m
MOQ: 1 Piece
Process: CNC lathe turning machining
Keyword: Stainless Steel Shafts
After Warranty Service: No service
Local Service Location: None
Port: ShenZhen

Are looking for the right supplier? CNC Machining Service —–Low- to High-Volume Sheet Metal Parts in as Fast as 1 DayOn-demand solutions Capabilities for all of your custom manufacturing applications from prototype to production CNC machiningWe combine the latest precision CNC milling and turning processes with proprietary technology to deliver high quality, on-demand parts Sheet Metal FabricationOffers punching, laser cutting, stamping, bending, and welding sheet metal services, Fabrication services range from low-volumeprototyping to high-volume production runs Injection MoldingInjection molding aim at cost-effective and quality conform, CZPT to provide you the best solution for tooling development. cost reduction and quality satisfaction are both priorities

Product NameShaft Collar
Tolerance+/-0.01mm, 100% QC quality inspection before delivery, can provide quality inspection form
MOQLow MOQ Start 1 Pcs ( No need mold cost ) , Many Customer found us make prototype product to save Investment Funds for Pre-R&D and Market Testing
Sample CostFree of Sample Cost. Normally is USD 35~110 per Style Of Special Design We Need Sample Charge, Can Refund when You Have Official Bulk Order.
Drawing AcceptedSolidworks,Pro/Engineer, AutoCAD(DXF,DWG), PDF etc.
Delivery Time1-25 days after order with prepayment based on products structure and quantity
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product processing capacity?
1.Main Materials
AluminumAl6061, Al6063, Al6082, Al7075, Al2571, Al5052, A380, etc.
Stainless SteelSS201,SS301,SS303, SS304, SS316, SS416, etc.
SteelMild Steel, Carbon Steel, 4140, 4340, Q235, Q345B, 20#, 45#, etc.
BrassC35600, C36000, C37700, C37000, C37100, C28000, C26000, C24000, C22000, etc.
CopperC11000, C12000, C12200, C15710, etc.
Iron20#, 45#, Q235, Q345, Q3458, 1214, 12L14, 1215, etc.
PlasticPOM, Peek, PMMA, ABS, Delrin, Nylon, PVC, PP, PC, etc
2. Surface Treatment
Stainless SteelBrushed and Polishing, Passivating, Sandblasting, Laser engraving, Gold Plating Etc.
SteelZinc plating, Oxide black, Nickel plating, Chrome plating, Carburized, Powder Coated
Aluminum PartsClear Anodized, Color Anodized, Sandblast Anodized, Chemical Film, Brushing, Polishing, Powder Coated, Nickel Plated Etc.
PlasticPlating gold (ABS), Painting, Brushing (Acrylic), laser engraving
Technical Support HangZhou Baijinxin Group is a professional at independent development and design. Our engineers are skilled at AUTO CAD, PRO ENGINEER, SOLID, SketchUp. 3D max WORKS and other 2D & 3D software. We are CZPT to design, develop, produce and deliver your PO according to your drawings, samples, or just an idea. control of non-standard products and OEM products.Quality Control1) Checking the raw material after they reach our factory——- Incoming quality control ( IQC)2) Checking the details before the production line operated3) Have a full inspection and routing inspection during mass production—In-process quality control(IPQC)4) Checking the goods after they are finished—- Final quality control(FQC)5) Checking the goods after they are finished—–Outgoing quality control(OQC) Here are the inspection reports before every shipment. Buyers Reviews? Company Profile Are you bothered by the following Points?● Waiting Day By Day for Quoting ● Unprofessional, Communicating Difficult ● Unpredictable ETA All Through ● After-Sale Unguaranteed ● Poor Quality ● Expensive PriceCome and Contact us:● Receiving a reply within 1 hour and receiving a quote within 24 hours. ● Profession Engineers Team Makes communication easy.● Predictable ETA All Through ● After-Sale Guaranteed. ● High Quality Accept 3rd Party Inspection. ●Competitive Price. HangZhou Baijinxin engineer team has more than 8 years of engineering experience on average (sheet metal fabrication, CNC machining, enclosure, bracket, chassis design, internal functional parts of products), fluent in English and communication barrier-free ,Improve communication efficiency and save time for customers. The leader of our enterprise is an Engineer, based on honesty and trustworthiness, and strict control the product quality and technology strictly, so as to avoid your worries in the future. High quality, on-time delivery, professional design, and one-stop service are the reasons for our long-term cooperation with famous customers HAN ‘s LASER, Formlabs, Samurai, Baxter, VELKASE, etc. As long as you give us the functionality, performance, or even the idea of the product, we can change the product from the idea to reality. Welcome to consult immediatelyCorporate philosophy: All problems end with us!! FAQ Q: Is your organization committed to the concept of total quality management?A: Yes, no matter in laser cutting, bending, or CNC machining, the workers will conduct the first sample inspection and random inspection during the processing to ensure the quality of the products.Q: How many checks are performed on a project?A: Usually, products will go through the following 4 inspections: incoming inspection, production first inspection, sampling inspection, and pre-shipment inspection. Among them, sampling inspection will be conducted multiple timesQ:Will you be CZPT to work with our engineering team to review drawings and provide quick, estimated pricing for desired changes?A:Yes, our engineers respond very quickly. If there is anything to be modified in the product, we can offer you a new price as soon as you tell us.Q:Is the material ROHS compliant?A:YesQ:Will your company sign an NDA?A:Yes

Types of Screw Shafts

Screw shafts come in various types and sizes. These types include fully threaded, Lead, and Acme screws. Let’s explore these types in more detail. What type of screw shaft do you need? Which one is the best choice for your project? Here are some tips to choose the right screw:

Machined screw shaft

The screw shaft is a basic piece of machinery, but it can be further customized depending on the needs of the customer. Its features include high-precision threads and ridges. Machined screw shafts are generally manufactured using high-precision CNC machines or lathes. The types of screw shafts available vary in shape, size, and material. Different materials are suitable for different applications. This article will provide you with some examples of different types of screw shafts.
Ball screws are used for a variety of applications, including mounting machines, liquid crystal devices, measuring devices, and food and medical equipment. Various shapes are available, including miniature ball screws and nut brackets. They are also available without keyway. These components form a high-accuracy feed mechanism. Machined screw shafts are also available with various types of threaded ends for ease of assembly. The screw shaft is an integral part of linear motion systems.
When you need a machined screw shaft, you need to know the size of the threads. For smaller machine screws, you will need a mating part. For smaller screw sizes, the numbers will be denominated as industry Numeric Sizes. These denominations are not metric, but rather in mm, and they may not have a threads-per-inch designation. Similarly, larger machine screws will usually have threads that have a higher pitch than those with a lower pitch.
Another important feature of machine screws is that they have a thread on the entire shaft, unlike their normal counterparts. These machine screws have finer threads and are intended to be screwed into existing tapped holes using a nut. This means that these screws are generally stronger than other fasteners. They are usually used to hold together electronic components, industrial equipment, and engines. In addition to this, machine screws are usually made of a variety of materials.
screwshaft

Acme screw

An Acme screw is the most common type of threaded shaft available. It is available in a variety of materials including stainless steel and carbon steel. In many applications, it is used for large plates in crushing processes. ACME screws are self-locking and are ideal for applications requiring high clamping force and low friction. They also feature a variety of standard thread forms, including knurling and rolled worms.
Acme screws are available in a wide range of sizes, from 1/8″ to 6″. The diameter is measured from the outside of the screw to the bottom of the thread. The pitch is equal to the lead in a single start screw. The lead is equal to the pitch plus the number of starts. A screw of either type has a standard pitch and a lead. Acme screws are manufactured to be accurate and durable. They are also widely available in a wide range of materials and can be customized to fit your needs.
Another type of Acme screw is the ball screw. These have no back drive and are widely used in many applications. Aside from being lightweight, they are also able to move at faster speeds. A ball screw is similar to an Acme screw, but has a different shape. A ball screw is usually longer than an Acme screw. The ball screw is used for applications that require high linear speeds. An Acme screw is a common choice for many industries.
There are many factors that affect the speed and resolution of linear motion systems. For example, the nut position and the distance the screw travels can all affect the resolution. The total length of travel, the speed, and the duty cycle are all important. The lead size will affect the maximum linear speed and force output. If the screw is long, the greater the lead size, the higher the resolution. If the lead length is short, this may not be the most efficient option.
screwshaft

Lead screw

A lead screw is a threaded mechanical device. A lead screw consists of a cylindrical shaft, which includes a shallow thread portion and a tightly wound spring wire. This spring wire forms smooth, hard-spaced thread convolutions and provides wear-resistant engagement with the nut member. The wire’s leading and trailing ends are anchored to the shaft by means appropriate to the shaft’s composition. The screw is preferably made of stainless steel.
When selecting a lead screw, one should first determine its critical speed. The critical speed is the maximum rotations per minute based on the natural frequency of the screw. Excessive backlash will damage the lead screw. The maximum number of revolutions per minute depends on the screw’s minor diameter, length, assembly alignment, and end fixity. Ideally, the critical speed is 80% of its evaluated critical speed. A critical speed is not exceeded because excessive backlash would damage the lead screw and may be detrimental to the screw’s performance.
The PV curve defines the safe operating limits of a lead screw. This relationship describes the inverse relationship between contact surface pressure and sliding velocity. As the PV value increases, a lower rotation speed is required for heavier axial loads. Moreover, PV is affected by material and lubrication conditions. Besides, end fixity, which refers to the way the lead screw is supported, also affects its critical speed. Fixed-fixed and free end fixity are both possible.
Lead screws are widely used in industries and everyday appliances. In fact, they are used in robotics, lifting equipment, and industrial machinery. High-precision lead screws are widely used in the fields of engraving, fluid handling, data storage, and rapid prototyping. Moreover, they are also used in 3D printing and rapid prototyping. Lastly, lead screws are used in a wide range of applications, from measuring to assembly.

Fully threaded screw

A fully threaded screw shaft can be found in many applications. Threading is an important feature of screw systems and components. Screws with threaded shafts are often used to fix pieces of machinery together. Having fully threaded screw shafts ensures that screws can be installed without removing the nut or shaft. There are two major types of screw threads: coarse and fine. When it comes to coarse threads, UTS is the most common type, followed by BSP.
In the 1840s, a British engineer named Joseph Whitworth created a design that was widely used for screw threads. This design later became the British Standard Whitworth. This standard was used for screw threads in the United States during the 1840s and 1860s. But as screw threads evolved and international standards were established, this system remained largely unaltered. A new design proposed in 1864 by William Sellers improved upon Whitworth’s screw threads and simplified the pitch and surface finish.
Another reason for using fully threaded screws is their ability to reduce heat. When screw shafts are partially threaded, the bone grows up to the screw shaft and causes the cavity to be too narrow to remove it. Consequently, the screw is not capable of backing out. Therefore, fully threaded screws are the preferred choice for inter-fragmentary compression in children’s fractures. However, surgeons should know the potential complication when removing metalwork.
The full thread depth of a fully threaded screw is the distance at which a male thread can freely thread into the shaft. This dimension is typically one millimeter shy of the total depth of the drilled hole. This provides space for tap lead and chips. The full-thread depth also makes fully threaded screws ideal for axially-loaded connections. It is also suitable for retrofitting applications. For example, fully threaded screws are commonly used to connect two elements.
screwshaft

Ball screw

The basic static load rating of a ball screw is determined by the product of the maximum axial static load and the safety factor “s0”. This factor is determined by past experience in similar applications and should be selected according to the design requirements of the application. The basic static load rating is a good guideline for selecting a ball screw. There are several advantages to using a ball screw for a particular application. The following are some of the most common factors to consider when selecting a ball screw.
The critical speed limit of a ball screw is dependent on several factors. First of all, the critical speed depends on the mass, length and diameter of the shaft. Second, the deflection of the shaft and the type of end bearings determine the critical speed. Finally, the unsupported length is determined by the distance between the ball nut and end screw, which is also the distance between bearings. Generally, a ball screw with a diameter greater than 1.2 mm has a critical speed limit of 200 rpm.
The first step in manufacturing a high-quality ball screw is the choice of the right steel. While the steel used for manufacturing a ball screw has many advantages, its inherent quality is often compromised by microscopic inclusions. These microscopic inclusions may eventually lead to crack propagation, surface fatigue, and other problems. Fortunately, the technology used in steel production has advanced, making it possible to reduce the inclusion size to a minimum. However, higher-quality steels can be expensive. The best material for a ball screw is vacuum-degassed pure alloy steel.
The lead of a ball screw shaft is also an important factor to consider. The lead is the linear distance between the ball and the screw shaft. The lead can increase the amount of space between the balls and the screws. In turn, the lead increases the speed of a screw. If the lead of a ball screw is increased, it may increase its accuracy. If not, the lead of a ball screw can be improved through preloading, lubrication, and better mounting accuracy.

China Customized CNC turning machining precision aluminium stainless steel Set Screw Clamping Shaft Collar     threaded shaft drawingChina Customized CNC turning machining precision aluminium stainless steel Set Screw Clamping Shaft Collar     threaded shaft drawing
editor by czh

China Standard Aluminum Spacers with Set Screw Double Split Clamping Threaded Shaft Collar with high quality

Product Description

High quality black or zinc galvanized steel/aluminum/Stainless steel/ Single Split shaft collar

Product Description

Shaft Collar is used for axial positioning of parts.
 

Types

1Solid Setscrew shaft collar,Hex bore shaft collar,One Piece shaft collar,Two

2.Piece shaft collar,Threaded shaft collar,Single split shaft collar,Double split shaft collar

3.Our products can be made according to Climax,Holo-Krome,Stafford,Ruland etc. 

Features

1.Effective on hard and soft shafts

2.Cost effective collar design

3.Easily installed where major disassembly would otherwise be required Simply slide these collars onto a shaft    and tighten the set screw to hold the collar in place.Collars are easy to adjust with their set screws.

Note 

1.Material:AL,Steel,Stainless steel,Alloy,Copper,Plastic

2.Finish: Black oxide, self-colour, oiled, zinc plated

3.Processes:Broaching/ Hobbing/ Slotting/tapping

4.Package:box/carton/wooden case

5.Lead time:20-35 days

6.ISO9001:2008 Certificated

Dimensions:

Product name: shaft collar,single split
Material:

Steel – Plain finish
Steel – Black Oxide finish
Steel – Zinc Plated finish
Stainless Steel

Metric Single split shaft collars:

Inch Single split shaft collars:

PACKING

Packaging
                      
    Packing  

 

We use standard export wooden case, carton and pallet, but we can also pack it as per your special requirements.

OUR COMPANY

ZheJiang Mighty Machinery Co., Ltd. specializes in offering best service and the most competitive price for our customer.

After over 10 years’ hard work, MIGHTY’s business has grown rapidly and become an important partner for oversea clients in the industrial field and become a holding company for 3 manufacturing factories.

MIGHTY’s products have obtained reputation of domestic and oversea customers with taking advantage of technology, management, quality and very competitive price.

 

Your satisfaction is the biggest motivation for our work, choose us to get high quality products and best service.

OUR FACTORY

Main Products:

Timing belt pulleys, timing bars, timing belt clamping plates.

Locking elements and shrink discs: could be alternative for Ringfeder, Sati, Chiaravalli, BEA, KBK, Tollok, etc.

V belt pulleys and taper lock bush.

Sprockets, idler, and plate wheels.

Gears and racks: spur gear, helical gear, bevel gear, worm gear, gear rack.

Shaft couplings: miniature coupling, curved tooth coupling, chain coupling, HRC coupling, normex coupling, FCL coupling, GE coupling, rigid and flexible coupling, jaw coupling, disc coupling, multi-beam coupling, universal joint, torque limiter, shaft collars.

Forging, Casting, Stamping Parts.
Other customized power transmission products and Machining Parts (OEM).

 

 

Application

 

1. Engineering: machine tools, foundry equipments, conveyors, compressors, painting systems, etc.

2. Pharmaceuticals& Food Processing: pulp mill blowers, conveyor in warehouse, agitators, grain, boiler, bakery machine, labeling machine, robots, etc.

3. Agriculture Industries: cultivator, rice winnower tractor, harvester, rice planter, farm equipment, etc.

4. Texitile Mills: looms, spinning, wrappers, high-speed auto looms, processing machine, twister, carding machine, ruler calendar machine, high speed winder, etc.

5. Printing Machinery: newspaper press, rotary machine, screen printer machine, linotype machine offset printer, etc.

6. Paper Industries: chipper roll grinder, cut off saw, edgers, flotation cell and chips saws, etc.

7. Building Construction Machinery: buffers, elevator floor polisher mixing machine, vibrator, hoists, crusher, etc.

8. Office Equipments: typewriter, plotters, camera, money drive, money sorting machine, data storage equipment, etc.

9. Glass and Plastic Industries: conveyor, carton sealers, grinders, creeper paper manufacturing machine, lintec backing, etc.

10. Home Appliances: vacuum cleaner, laundry machine, icecream machine, sewing machine, kitchen equipments, etc.

 

FAQ

Q: Are you trading company or manufacturer ?
A: We are factory.

Q: How long is your delivery time?
A: Generally it is 5-10 days if the goods are in stock. or it is 15-20 days if the goods are not in stock, it is according to quantity.

Q: Do you provide samples ? is it free or extra ?
A: Yes, we could offer the sample for free charge but do not pay the cost of freight.

Q: What is your terms of payment ?
A: Payment=1000USD, 30% T/T in advance ,balance before shippment.
If you have another question, pls feel free to contact us as below:

 

Contacts

We warmly welcome friends from domestic and abroad come to us for business negotiation and cooperation for mutual benefit. To supply customers excellent quality products with good price and punctual delivery time is our responsibility.

Any question or inquiry, pls contact us without hesitate, we assure any of your inquiry will get our prompt attention and reply!

Screw Sizes and Their Uses

Screws have different sizes and features. This article will discuss screw sizes and their uses. There are 2 main types: right-handed and left-handed screw shafts. Each screw features a point that drills into the object. Flat tipped screws, on the other hand, need a pre-drilled hole. These screw sizes are determined by the major and minor diameters. To determine which size of screw you need, measure the diameter of the hole and the screw bolt’s thread depth.

The major diameter of a screw shaft

The major diameter of a screw shaft is the distance from the outer edge of the thread on 1 side to the tip of the other. The minor diameter is the inner smooth part of the screw shaft. The major diameter of a screw is typically between 2 and 16 inches. A screw with a pointy tip has a smaller major diameter than 1 without. In addition, a screw with a larger major diameter will have a wider head and drive.
The thread of a screw is usually characterized by its pitch and angle of engagement. The pitch is the angle formed by the helix of a thread, while the crest forms the surface of the thread corresponding to the major diameter of the screw. The pitch angle is the angle between the gear axis and the pitch surface. Screws without self-locking threads have multiple starts, or helical threads.
The pitch is a crucial component of a screw’s threading system. Pitch is the distance from a given thread point to the corresponding point of the next thread on the same shaft. The pitch line is 1 element of pitch diameter. The pitch line, or lead, is a crucial dimension for the thread of a screw, as it controls the amount of thread that will advance during a single turn.
screwshaft

The pitch diameter of a screw shaft

When choosing the appropriate screw, it is important to know its pitch diameter and pitch line. The pitch line designates the distance between adjacent thread sides. The pitch diameter is also known as the mean area of the screw shaft. Both of these dimensions are important when choosing the correct screw. A screw with a pitch of 1/8 will have a mechanical advantage of 6.3. For more information, consult an application engineer at Roton.
The pitch diameter of a screw shaft is measured as the distance between the crest and the root of the thread. Threads that are too long or too short will not fit together in an assembly. To measure pitch, use a measuring tool with a metric scale. If the pitch is too small, it will cause the screw to loosen or get stuck. Increasing the pitch will prevent this problem. As a result, screw diameter is critical.
The pitch diameter of a screw shaft is measured from the crest of 1 thread to the corresponding point on the next thread. Measurement is made from 1 thread to another, which is then measured using the pitch. Alternatively, the pitch diameter can be approximated by averaging the major and minor diameters. In most cases, the pitch diameter of a screw shaft is equal to the difference between the two.

The thread depth of a screw shaft

Often referred to as the major diameter, the thread depth is the outermost diameter of the screw. To measure the thread depth of a screw, use a steel rule, micrometer, or caliper. In general, the first number in the thread designation indicates the major diameter of the thread. If a section of the screw is worn, the thread depth will be smaller, and vice versa. Therefore, it is good practice to measure the section of the screw that receives the least amount of use.
In screw manufacturing, the thread depth is measured from the crest of the screw to the root. The pitch diameter is halfway between the major and minor diameters. The lead diameter represents the amount of linear distance traveled in 1 revolution. As the lead increases, the load capacity decreases. This measurement is primarily used in the construction of screws. However, it should not be used for precision machines. The thread depth of a screw shaft is essential for achieving accurate screw installation.
To measure the thread depth of a screw shaft, the manufacturer must first determine how much material the thread is exposed to. If the thread is exposed to side loads, it can cause the nut to wedge. Because the nut will be side loaded, its thread flanks will contact the nut. The less clearance between the nut and the screw, the lower the clearance between the nut and the screw. However, if the thread is centralized, there is no risk of the nut wedgeing.
screwshaft

The lead of a screw shaft

Pitch and lead are 2 measurements of a screw’s linear distance per turn. They’re often used interchangeably, but their definitions are not the same. The difference between them lies in the axial distance between adjacent threads. For single-start screws, the pitch is equal to the lead, while the lead of a multi-start screw is greater than the pitch. This difference is often referred to as backlash.
There are 2 ways to calculate the pitch and lead of a screw. For single-start screws, the lead and pitch are equal. Multiple-start screws, on the other hand, have multiple starts. The pitch of a multiple-start screw is the same as its lead, but with 2 or more threads running the length of the screw shaft. A square-thread screw is a better choice in applications requiring high load-bearing capacity and minimal friction losses.
The PV curve defines the safe operating limits of lead screw assemblies. It describes the inverse relationship between contact surface pressure and sliding velocity. As the load increases, the lead screw assembly must slow down in order to prevent irreversible damage from frictional heat. Furthermore, a lead screw assembly with a polymer nut must reduce rpm as the load increases. The more speed, the lower the load capacity. But, the PV factor must be below the maximum allowed value of the material used to make the screw shaft.

The thread angle of a screw shaft

The angle between the axes of a thread and the helix of a thread is called the thread angle. A unified thread has a 60-degree angle in all directions. Screws can have either a tapped hole or a captive screw. The screw pitch is measured in millimeters (mm) and is usually equal to the screw major diameter. In most cases, the thread angle will be equal to 60-degrees.
Screws with different angles have various degrees of thread. Originally, this was a problem because of the inconsistency in the threading. However, Sellers’s thread was easier to manufacture and was soon adopted as a standard throughout the United States. The United States government began to adopt this thread standard in the mid-1800s, and several influential corporations in the railroad industry endorsed it. The resulting standard is called the United States Standard thread, and it became part of the ASA’s Vol. 1 publication.
There are 2 types of screw threads: coarse and fine. The latter is easier to tighten and achieves tension at lower torques. On the other hand, the coarse thread is deeper than the fine one, making it easier to apply torque to the screw. The thread angle of a screw shaft will vary from bolt to bolt, but they will both fit in the same screw. This makes it easier to select the correct screw.
screwshaft

The tapped hole (or nut) into which the screw fits

A screw can be re-threaded without having to replace it altogether. The process is different than that of a standard bolt, because it requires threading and tapping. The size of a screw is typically specified by its major and minor diameters, which is the inside distance between threads. The thread pitch, which is the distance between each thread, is also specified. Thread pitch is often expressed in threads per inch.
Screws and bolts have different thread pitches. A coarse thread has fewer threads per inch and a longer distance between threads. It is therefore larger in diameter and longer than the material it is screwed into. A coarse thread is often designated with an “A” or “B” letter. The latter is generally used in smaller-scale metalworking applications. The class of threading is called a “threaded hole” and is designated by a letter.
A tapped hole is often a complication. There is a wide range of variations between the sizes of threaded holes and nut threads, so the tapped hole is a critical dimension in many applications. However, even if you choose a threaded screw that meets the requisite tolerance, there may be a mismatch in the thread pitch. This can prevent the screw from freely rotating.

China Standard Aluminum Spacers with Set Screw Double Split Clamping Threaded Shaft Collar   with high qualityChina Standard Aluminum Spacers with Set Screw Double Split Clamping Threaded Shaft Collar   with high quality