Day: July 7, 2015

Screw Head Types and their Uses

At Mutual Screw and Supply, we field several calls from our esteemed clients, seeking help in choosing right bit of screw head types, appropriate for their requirements.

Different of screws with different types of Screw heads

Here’s a brief yet comprehensive guide to screw head types and drives. Read on!

When your jobs requires usage of screws then always remember to go for the right type of screw driver. While most of the screws look alike, but their screw heads are rather different, thereby enabling you to go for distinct screw drives, which fit with the heads of your chosen screws. For instance, Phillips and Pozidriv are hard to be distinguished from a distance of 10 feet. But both of these fasteners do feature different heads and simultaneously they require different kinds of screw drives for their installation.

Phillips and Frearson Screw Heads

Here is a list of different types of screw heads.


Phillips Screw Head


Invented by Henry Phillips, this kind of drive was explicitly designed to cam-out (it’s a method in which the screw driver glides out of the screw head, when it is driven and the torque which is required to turn the fastener crosses a certain amount) when the screw was bogged down, so as to prevent any damage occurring to the head, nonetheless affecting the driver. This particular design however created relative difficulty in developing torque, thereby restricting into the old drivers.

Other hardware companies therefore discarded the Phillips concept, as it created a relatively tangled and sunken socket shape in the head of the rivets.

These heads are usually designated in 7 types, depending upon the size of the screws and they include 000, 00, 0, 1, 2, 3, and 4.


A Slotted Screw Head


This is the most commonly used screw drive and is commonplace everywhere in the world, although its traditional usage is declining gradually, because of its slipping nature whenever heavy torque is applied over it.

Phillips Tamper-resistant

A Phillips tamper Resistant Screw Head


Most of the screw drives available in the market are tamper-resistant because of their vagueness. The one-way and breakaway drives fall under this category, which require specialized tools to destroy the rivet while unscrewing them. The high-end quality of such drives is used on home electronics. Such feature even helps the professional technician to repair the equipment easily, without having to return the piece to the manufacturer.


Quadrex Screw Head


Quadrex, which is also known as the Phillips/square screw drive, is actually a combination of Robertson and Phillips screw drives. While an ordinary Robertson or Phillips tool can be used for its application, there is still a specialized tool for it, which enhances the surface area between the rivet and the tool, thereby enabling to handle more torque.

Earlier, this drive was sold under the name Deck Mate, which is now considered as other kind of drive.


Supadriv Screw head



The Supadriv, which is also spelt as ‘Supadrive’ is almost similar to Pozidriv by design and people often get confused between these two.

Anyways, this particular drive can be identified by two of its unique features. It secondary blades are larger and are of equal thickness. Moreover, it has got a superior bit, thereby making the installation procedure more efficient, producing less cam-out.


Pozidriv Screw Head



The Pozidriv is the enhanced version of the Phillips screw drive. It is patented by American Screw Company and Phillips Screw Company. Many consider this name as an abbreviation of ‘positive drive’. The major advantage of such kind of drive is its likelihood to prevent cam-out, thereby enabling greater torque to be employed. As per ANSI, it is considered as type IA and is quite similar with Supadriv screw driver.


Frearson Screw Head


The Frearson, which is also known as the Reed and Prince Screw head type, is somewhat similar to Phillips, but the only difference is that it features a pointed 75° V shape.

It is superior to Phillips drive in one way, as its bit can fit all screw sizes. It is mostly found in marine hardware and needs a specialized screw driver under the same name. Its tool recess features sharp cross, thereby enabling higher torque to be applied, unlike the rounded Phillips head type.

Hexalobular socket

Hexaloboular Socket screw Head


The hexalobular socket screw driver, which is rather popular as Torx and star drive, is a star-shaped recess as the name suggests, featuring 6 rounded points.

It is specially designed to allow higher torque transfer from the driver to the bit, as compared to other drives. The Torx is mostly used in electronics and automotive industry, as it is highly resistant to cam-out and even reduces the need to go down with the drive tool.

Torax Screw Head


Few Tips Help Buy Accurate Metric Tap Bolts

Machines as well as components, which are joined with screws and bolts, feature distinct torque specifications. Fasteners, such as metric tap bolts, are manufactured specifically to go through a nut/hole, which is pre-tapped to create a mating thread for that fastener. These rivets are designed to be conveniently used by any pneumatic tools or a wrench.

Metric Tap Bolt

How to identify metric tap bolts

People looking for these types of bolts may easily get confused with the American bolts. They are quite different in the measuring technique. While American bolts use the number of threads/inch as a measurement, the metric bolts use the distance between the threads.

Metric Bolts marked with Numbers to Indicate their Relative strength

These bolts are normally measured in millimeters as the standard reporting unit.

How to measure

The shank diameter of this bolt should be measured first, which is the distance from one side of the bolt to the other through the center

Metric grade to SAE grade Comparison

The number of threads should now be counted. Now the distance should be divided by the number of threads. For instance, if 10 threads make one centimeter, the thread length should be of 1 mm

The length of the bolt should be measured i.e. from the start of the head to the end of the bolt

Metric tap Bolt and Nut Technical Specifications

Now note the reading as such – diameter x distance between threads x length. For e.g. if a bolt has diameter of 2 cm, 1 mm between the threads and length of 25 mm then it would read as  “2x1x25”

Torque Specifications

Like other fasteners, the metric tap bolts are also enabled with torque specifications. The torque refers to the total amount of force, which is required to turn the nut and bolt around a fixed point.

Internal and External Thread Graph of Metric tap Bolt

In the metric system, bolts are usually expressed as per their diameter, the distance between their threads. For e.g. a fastener with a size of 12×1.75×30 suggests that the fastener is 12 mm in diameter with a length of 30 mm and 1.75 mm of distance between the threads.

In the metric nuts, these bolts are categorized under various grades. However, the metric nuts do not have any identification marks and are rather listed by thread spacing and diameter.

Different Heads and Sizes of Metric tap Bolts

Low Grade Specification

A low grade 6 mm metric tap bolt features maximum torque values ranging between 3 to 5 foot-pounds. Similarly, a 8 mm bolt will feature torque ranging between 8 and 12 foot-pounds. And a 10 mm metric bolts will feature torque between 15 and 22 foot-pounds.

8.8 Grade mark Metric Hex Bolt

8.8 Grade Specification

A 14 mm metric tap bolt with a grade of 8.8 will require 101 foot-pounds of torque. A 16 mm of bolt will require 146 foot-pounds of torque. An 18 mm bolt requires 201 foot-pounds of torque and a 20 mm bolt requires 285 foot-pounds of torque.

Typical ISO bolt and nut Markings

FYI: The bolt torques are flexible and depends heavily on the lubrication of the bolt. The above mentioned specifications are for dry and unlubed metric bolts.

Dimensions of metric tap bolts


The shank or the threaded portion of the bolt is defined by the size. The shank’s diameter is usually used as the primary measurement. the length of the shank varies greatly with the width. Those two measurements are determined by suppliers like Mutual screw, to help customers identify the metric tap bolts.

Internal and external thread graph and specifications of Metric bolts

An M10x20 metric bolt is enabled with a 10 mm shank which is 20 cm long.


The diameter between the flat sections of the head is always 1.8 times more than the diameter of the shank. An M10 metric bolt with a 10 mm of shank will have a 16 mm of hex head. the shank size can be calculated by measuring the head’s dimension and dividing it by 1.8.

Specification Requirements of Metric Tap Bolts

How to buy metric tap bolts

These bolts are usually sold based on their length, width, thread size and diameter. Some of these rivets are also labeled as per their strength. In our store, these items are sold as per their size and coarse thread.

Before purchasing these rivets, always make sure your measurements are in metric units.

Mutualscrews Metric tap bolt

Few tips to help buy accurate bolts

#Always determine the diameter of the product, you’re willing to buy for your requirement

#The thread distance is the second factor to be considered

Various Sizes of Metric Tap Bolts

#After you’re done with diameter and the thread distance, it’s now time to look for the accurate length, your job requires.

Dog Point Set Screw: The Most Commonly Used Set Screw

A socket set screw is a specific type of threaded fastener, which usually does not feature a head. Unlike other kind of commonly used rivets, this metal piece is basically an adjustment device generally used to develop axial chunk. Such kind of screw comes handy and is used for multiple uses. Plus, it is also available in various types, the most common type, being the dog point set screw.

Such type of fastener is used to clutch body parts like collar, gear, sleeve, coupling etc. into an axle, so as to prevent relative oscillation. The socket feature helps such kind of screw to effectively rotate in a desired direction. The sockets are available in various types, including fluted socket, square head, screwdriver slot, hexagon socket and much more in the list.

You should always consider the point of your fastener before purchasing it. You should know which model is suitable for your job. The point of a rivet is the area, which rotates against the shaft during penetration. The point selection is usually done by determining the nature of the functionality. The point is available in various types, which are as follows:

Dog Point Set Screw:

It is the most common type, mostly used for fixing into any permanent location of one surface to the other. It features a broad flattened end, followed by its angular threads ending before just above the tail. The fastener’s end is placed in the already drilled hole in shaft or on a flat surface. It is often replaced with the dowel pinions and always works well against the must rugged surface or hollow tubing.

Flat type:

Such kind of point is used on those surfaces, where parts are always replaced or re-set. IN this frequent application, such kind of point helps prevent damage or any kind of wear and tear.

Knurled Cup:

This type of point is used for permanent locations, including collars, gears, knobs, pulleys and shafts. This particular head is able to resist more amount of vibration.

Plain Cup:

This point is used for style set screw. It is usually used in permanent as well as fluctuating locations mainly on shaft, featuring hardness differential of 10-15 Rockwell C points and in those areas, where the cutting of the cap is acceptable.

You can select any of these above set screws, determining the nature and requirement of your job.

Glider Bearings: Essential for Building a Rocker Chair

Planning to construct a rocker? Then you’ll surely need some suitable glider bearings. This particular hardware kit is an essential necessity for building any type of glider, be it wooden, net or anything kind of material. If you’re planning to spend your winter vacation in any national park and your family is keen in camping then I highly suggest you to carry such type of kit.

Glider Bearings

With this help, you can easily hang a net bed between two trees or can easily carry your rocker chair to the woods. In order to build a rocker, you’ll have to make a hole of around 1-1/8 inches for the bearings to get easily fitted in. You should always use hardwoods. The nuts, bolts and washers should be of 3/8 inches. The screws must feature #6 square recess drives. In this way, you can build up a simple arrangement as used by the professional manufacturers.

Even if you’re not going into the woods, you may be thinking of implementing a net hanging bed in your courtyard. It will be quite expensive in calling down a professional carpenter for this simple job. Instead, you can volunteer to do fix this job. All you need is an appropriate place and required amenities. And with the availability of accurate glider bearings, you can hang your gliding bed on your own.

You can take the help of the Internet. These days, almost every other item, be it apparel, gift or any hardware supply can be easily fetched online. Such tiny essentials are also available online. The Mutual Screw and Supply is a leading web store, dealing with such kinds of metal round objects. You can browse through the site to find the product, best suiting your requirement. Besides, manufacturers of rocker chairs also rely upon this company and order items on bulk amounts. With the minimal shipping charge, you can easily avail your item in a cost-effective way.

The glider bearings are unique hangers, featuring ball bearings at both ends. They give your glider projects an ultra-smooth, back-and-forth action. These are made up of rust resistant steel and usually measure 7-1/2″ between centers and have a 1-1/4″ offset.

History of Robertson Screws

If something that can distinguish the Canadian hardware industry from American then it is the Robertson screw, which is also known as the square socket screws and Scrulox.

Square Socket Head Screw

This is one of the highly popular specialized screws, which features a square-shaped socket on its head and the protrusion on the tool is also square-shaped. Both parts of the screw feature a taper, thereby enabling the fastening work much faster and easier as well. Besides, such features also help the screw to stick to the tool tip without any manual support.

In this edition, we’ll be discussing about the history of Robertson screws, which are commonplace in Canada. Read on!

Here is how Robertson Looks

It was a pleasant summer day in 1906, when businessman, Peter Lymburner Robertson was exhibiting a spring-loaded screwdriver before his clients. Accidentally, the driver slipped and he eventually cut his hand. This particular incident provoked him to invent a more advanced screwdriver and some definite set of screws, which could fit this driver. He invented the socket head screw, which revolutionized the entire hardware industry.

Thus, the Robertson screws – the best-kept secret outside of Canada were conceived and became a huge hit soon after it hit the market.

These fasteners are arguably considered as the biggest invention in the fastener industry of the 20th century.

Technical view of a Square Socket Head screw

His specially designed square socket screws and the driver gave a tighter grip than any usual slot and rarely slipped. Robertson worked hard on his invention, which addressed all those issues and finally developed a machine to manufacture screws, with such unique designs.

In those days, the newly developed fasteners were soaring high and had almost dominated the entire hardware industry.

They became favorites among the hardware manufacturers and craftsmen, mostly because of their self-centring feature and that they could be easily driven even by one hand. Moreover, they reduced the risk of product damage and increased the productivity, due to which heavy-duty industries were also clinging towards these fastening objects.

20th centurys Robestson Socket head Screws

One of the early hotshot clients for these screws was the Fisher Body Company, which used to design wooden body parts for Ford cars in Canada. They used 4-6 gross of Robertson screws in manufacturing Model T and they even convinced the Father of these fasteners to invent another specialized type i.e. socket screws for metal, so that they could easily match with the metal body parts of Model A, launched by Fords during that period.

Robertson Screws Used in wooden parts of Old Model Ford cars

But have you ever thought any brand, which became such a huge success didn’t go beyond the boundaries? Why those screws were not found outside of Canada, when they were so much good enough for manufacturers like Ford?

By going deeply into this factor, inventors/designers can learn a great lesson.

When Ford was testing the Robertson screws to employ with their assembly line, they discovered that by using those advanced fasteners, they could actually save up to 2 hours of their assembly time per vehicle.

And in order to protect this huge advantage, they made a license agreement with Robertson, stating that he won’t be having any ownership of his screws in future, so that he couldn’t sell his patent items to other companies.

However, Robertson had slowly expanded his business to Europe, but to his bad luck, World War 1 broke out and his Europe project faced a huge setback. He still emerged as a winner, as this time he was flying high with a blossoming project and felt that signing the agreement with Ford would be in best of his interests.

Robertson Screw Head

As legend goes, somebody else rises and bites the dust. Few years later, another big name rose in the market by the name of Phillips.

Robertson ran his Robertson Screw Company till his death in 1951. Today, this company has grown over 600 employees, with 120 of them belonging to his hometown Ontario in Milton.

Mutual Screw Announces 5% Off on All its Items Till the Year End

We are quite amused to announce that we are now offering a 5% off on our items and this offer is valid till the year end i.e. 31st Dec’ 2012. Although the East Coast has been hugely devastated due to Hurricane Sandy and the construction industry has received a major blow, still we have had a blissful year. And we strongly believe the credit goes to our esteemed customers. We have therefore come up with a noble way of offering our sincere gratitude to our clients through our Promo Code “2012”.

We, at Mutual Screw and Supply, have always worked towards enhancing our services, so as to render maximum benefits to our customers. Being in the hardware supply industry for over 65 odd years, we have grown with our enterprise and have now become a leading brand in the global market as well. And it has been made possible through the loyalty and support; we have been getting from our clientele.

Till the year end, our customers can avail this offer, by simply using the promotional code, 2012. We are always grateful for believing in us and forging upon us the trust, which is indeed essential behind every business. Through this discount, we are just trying to convey our message to each of our customer, about how grateful we are for keeping us indulged in their services.

Today the online market is flooded with numerous web stores, dealing with hardware supplies and with the increasing usage of online shopping medium, the competition has grown to a much higher level. Instead of keeping our heads high in the industry, we rather believe in providing quality service, which has always been the secret recipe behind our success.

This is also true that this year is ending on a bit tough note with the aftermath of natural calamities, but we are always functional and are already active in support task by putting in refurbishing efforts. While the already devastated properties are confident with a dramatic make over by early next year, we have also laid out a brand scheme, where we’ll be unveiling an array of new products with advanced features in 2013.

We look forward to the opportunities 2013 would impart on our profession and industry. But right now, we are quite confident our discount offer, under the promo code 2012, would surely be beneficial to our customers and service partners.

Types and Features of Plastite Screws

Our featured product for this month is the Stainless Steel Phillips Flat Head Plastite screws, which offer definite reverberation shield and consistent high quality performance in spite of frequent cluster by piercing into normal tapped holes. This is certainly a penny-saving alternative for the 48-2 Thread Rolling Screws, which always meets technical specifications.

Plastite Screws

Such type of screw features longish holding power, when it comes to plastics. It features an itemized thread profile, a tribolar strand arrangement, offering maximum holding capacity and detention to fluctuating external forces. Besides, this particular fastener is easy to drive i.e. its three layered thread pattern enhances movement of the object between the strands, thereby reducing the effort required to pierce the screw into the plastic surface.

Some salient features of Stainless Steel Phillips Flat Head Plastite Screws:

• Feature diverse range of drives, head patterns and materials to meet specific requirements.

• Specially designed for plastics.

• Feature slightly dwindled point and twin lead threads, so as to execute hassle free screw installation.

• This screw can drive at double the rate of a pitch single lead.

• Its thread enhances grip, thereby lessening pull-out and stripping.

• The design improves the failure torque in plastic objects.


These particular fasteners are available in huge varieties. Depending upon your requirement, you can go accordingly. The Internet can be of great help. You would get a comprehensive idea about this particular metal piece, their types, uses and availability. The most common types include the 18/8 Stainless Steel Phillips Flat Head Alternative 48-2 Thread Rolling Screws, 18/8 Stainless Steel Phillips Flat Undercut Head type,  410 Stainless Steel Phillips Pan Head type,  410 Stainless Steel Six-Lobe Pan Head type, Steel Black Zinc Bake & Wax Six-Lobe Pan Head and so on.

If you’re confused of which particular model to choose, you can always take the help of the customer support service. The World Wide Web is flooded with numerous websites dealing with such items. One such popular one is the Mutual Screw and Supply. You’ll get a detailed knowledge about the Plastite screws over here. So browse well and happy shopping!

Installing ITW Buildex Cement Board Screws

It is always necessary to use the exact type of fastener, say screws in certain conditions, so as to make sure that the installation procedure is executed effectively. And moreover, in the long run the correct usage of screw keeps it firmly fastened to the surface. You should always go for a company, say ITW Buildex, which has been in the hardware supply industry for over four decades, consistently working on enhancing its quality and services.

There are various types of screws available in the market, required for various kinds of jobs. The concrete screw is a very special type of fastener, specially designed to pierce its own threads into an already drilled hole on the surface made up of concrete, block, brick etc. The brand name Cement Board & Fiber Cement Board Screws is popular product, being sold over under this banner.

It was launched in early 80s and was highly popular because of its functionality even when there was less to no option for online branding. Such kind of screw can be easily installed and features enhanced pull-out shield and durable fixing values.

Cement Board & Fiber Cement Board Screws
In the concrete planting industry, the threads of such kinds of metal pieces are popularly called as “High-Low” screws. The threads of such screws enable quick dust removal during the installation process. Such strands also enable the fasteners to pierce in consistently, thereby giving high standard performance. The removal of dirt is relevant, as the dust present in the hole may interfere in the screwing process. Therefore, you should make sure that you’ve removed the dirt from the hole as well as from the thread.

Installing Cement Board ITW Buildex Screws

The installation procedure is quite simple. It can be done in three simple steps:

By using an accurate sized carbide capsized ashlar bit and a hammer drill, you can now drill a pilot hole of about 1/4th inches deep than the suggested anchor fastening

Now you need to clear the hole of the entire fragments

Now by using a standard drilling machine along-with an appropriate Phillips socket/hex, you can insert the metal screw into the already drilled hole until this fastener is completely pierced

You should be rather careful and should take care that you have not over-tightened the ITW Buildex screw, as this will cause the fastener to spin within the hole, thereby stripping the threads.

Now Get Rid of Squeaky Floor with Plywood Screws

Plywood screws, which are also known as chipboard screws are self-tapping screws, featuring thin shaft and coarse threads. These fasteners are made up of either wood dust or wood chips and resin, and as the name suggests, these screws are mainly in plywood and other soft wood surfaces.

These rivets are made to clinch this composite surface, so as to withstand loosening. The screws firmly hold either two plywood or any chipboard to other materials, say natural wood.

Apart from wooden works, these screws are highly recommended for squeaky floors as well. Recently one of our esteemed clients faced an issue with pressboard sub-flooring in his 20 years old house. While his upstairs flooring was creaking under the carpet, the downstairs floors jolt the entire house whenever stepped on promptly.

His main concern was to stop those high-pitched annoying sound and if he should go for another layer of plywood over the existing flooring? He was also interested in replacing the entire floor.

Playwood Screws for wood floors

So, this is what we had suggested him. Read on!

Instead of spending huge bucks in replacing the entire flooring, you can always go for an additional layer of plywood, which will definitely resolve all those issues. We highly recommend you to go for thicker material, as thicker the size would be, the degree of sound transmission would be reduced to more extent.

And yes, it’s always possible to fasten the existing wooden surface with the new layering. You’ll have to mark out the old nailing patterns, which should be in a gap of minimum 16 inches. Our aim should be enabling every new fastener with a supporting beam. By doing this, the squeaks will be reduced to a great extent and will even laminate properly the new layers along-with the base.

The plywood screws are the most ideal supplies required for fastening and you can even go for gluing, thereby strengthening the grip even more.

Different Sizes Of Play Wood Screws

In the meanwhile, do not forget about the sap, which pulls this surface up. So, better fasten it with those screws.

And do not try compromising with the quality of the screws, as this is definitely not a place to think about cost-cutting. So purchase the plywood screws in ample quantity and insert screw at every 4-6 inches of gap at the seams and at every 6-8 inches of gap in the field.

This is indeed an effective method, giving away long lasting results.

Much better looking wood floor with playwood screws

If your plywood is of 5-8 inches thick then you should consider those screws, which are at least 2 and 1/2 inches long, so that they can get a nice grip. However be warned that you don’t have any radiant heating line or plumbing beneath this surface.

We suggest you to go for an half inch plywood for the layering and you can even bowl over the seams from the existing surface. You can go cheap on the facings for the plywood to save from the recent hike in their pricing. For instance, you can go for CCX PTS, which exactly works as the ‘A’ grade material or you can even opt for OSB, which works well under the carpet.

The rooms with carpets need a little adjustment, as you would have to manage with the closets and swing doors for proper installation. You need to build a carpet shelf by raising the level of the carpeted areas.

But the major problem arises in areas, where you’re thinking of installing vinyl or linoleum flooring. For this, you’ll need a third layer of chipboard or particle board and so also the have to determine the size and thickness of plywood screws.

Not to mention, stairs are another nightmare. You can easily face trip hazards and in order to prevent this, you should confirm that the building code should have a minimum gap of at least 3-8 inches between the stairs, but the height should not exceed above 8.

Copper Flat Washer Specifications

A copper flat washer is a thin, disk-shaped plate, featuring a hole in the middle, which is used to disburse the weight of a threaded fastener, either a screw or a nut.

Copper Flat Washers

This copper piece is also used as a belleville washer, wave washer, spacer, wear pad locking device, preload indicating device and is also used to reduce the vibration. Its outer diameter is twice the width of its inner diameter.

A washer usually comes in three types: plain or flat washers, spring washers and locking washers. A copper flat washer distributes the load, thereby eliminating the damage to the surface. It is also used to render some sort of caulking or electrical insulation.

The spring washers, which feature axial flexibility, are used to prevent from fasteners getting loosen due to vibrations. The locking washers are also used to prevent the loosening of the fasteners by eliminating unscrewing rotation of the device.

various Types of Copper Flat Washers

The ANSI (American National Standards Institute) has given a standardization for the the flat washers. They can be summarized as

  • Form A = Normal Diameter, Normal Thickness
  • Form B = Normal Diameter, Light Thickness
  • Form C = Large Diameter, Normal Thickness
  • Form D = Large Diameter, Light Thickness
  • Forms E to G relate to Black Metal Washers

ANSI Standards of Flat Washers

The fastener companies use nuts, bolts and screws to fasten various objects. The manufacturers make use of flat washers, as they help builders screw nuts into big holes. These are available in several varieties, categorized under coating, size and material composition.

The highest quality washers are normal used in bolted joints, mainly due to the amount of the pressure the bold joints exert.


Detail Picture of Flat Washer



The copper flat washers are thin circular plates, which are specially designed to match with various types of nuts, according to Mutual Screw, a well-known fastener online dealer.

The washer normally goes through the longer part of the screw or bolt and creates a blockade between the device in contact with the nut and the head of the nut.

Clear Picture of Flat washer Usage spots

The builders also use these small circular plates when they are working with holes larger than the nut itself.


The width of a flat copper washer usually ranges from 3/16″ to 1/4″, although there are some specialized thicker washers, which are as thick as 1″ as per the ANSI. These specialized washers eliminate the risk of cupping, which occurs when the bolt gets into the object.

Thickness Diagram of Flat washers

Metallic Composition

These are available in various sizes and materials. The most commonly used are made up of copper, as these have high tensile strength. These pieces are also available in other materials as well, such as nickel-chromium-molybdenum, silicon-manganese, chromium, chromium-vanadium as per Global Spec.

Even these are available in titanium as this material is cheaper and is durable enough to enable stronger flat washers.

Technical Specifications of Different Flat Washers

Technical Specification

  • Item: USS Washer
  • Type: USS
  • Material: Steel HV-140
  • Hardness: HV 140 – 250
  • Finish: Copper
  • Fits Bolt Sizes: 1/4″
  • Inside Diameter: 5/16″
  • Outside Diameter: 3/4″
  • Thickness: 1/16″
  • Thickness Tolerance: 0.051-0.08″
  • Color: Silver
  • Application: Bearing Surface for Fasteners and Fixtures
  • For Use: With Screws and Bolts
  • Meets/Exceeds: ANSI B18.22.1

Metric Standard Flat Washer Technical specifications

Non-metallic Composition

The flat washers are also available in non-metallic materials as well. The manufacturers use polyester to create high tensile strength and this material also helps in enabling the washers wrinkle and abrasion resistant.

Poly-carbonate is also used, which features opacity and renders abundant strength. Sometimes, the acetyl materials are also molded to manufacture washers, s they have inherent lubricity and are highly chemical resistant.

Washers Used in a Machine

Other non-metallic usable materials include leather, nylon, ABS, rubber, asbestos, felt, polyethylene, Polyvinyl Chloride etc.


Manufacturers add various types of finishes to these types of fasteners. They create an anodize coating by oxidizing the aluminium surface of the device, thereby creating an oxide coating. This coating acts as a shield for the flat washer. The scientists also glavanize steel and iron along-with molten zinc, so as to increase the washer’s service life.

Flat Washer finishes

The flat washers are also available in other finishes, such as nickel, tin, zinc chromate, black oxide, zinc and phosphate.

Where to Buy

Copper Flat washers in various sizes