When it comes to choosing the correct product for any application, consumers are spoiled for choice with a greater selection of products than ever before.

Constant new designs, improved materials, advanced features, and benefits stated on labels, allow for easy differentiating between suppliers, but what impact does this have when it comes to the decision of a suitable Diamond blade?

With a multitude of options to be used for cutting applications on tiles, be it glazed for interior floors, or raw tiles for outdoor walkways, the first step to consider, is the desired finish after the application has been completed, with the hardness and composition of the material. Being a popular cutting tool for tiles, Diamond blades are available in Segmented, Continuous and Turbo rims.

Generally, the segmented rim produces a faster cut, with some chipping of the cutting edge due to the design of the segments. The slots allow for greater dust extraction and cooling, thus virtually reducing the need for a liquid coolant. The continuous rim, on the other hand, though providing the slowest cut reduces edge chipping to almost none, providing a smooth, clean cut due to the solid rim.

In certain cases where your application requires both a smooth and fast cut, the turbo rim will be the best choice. This diamond blade design offers a comparable cutting time to the segmented blade, producing a better finish, with the corrugations allowing for effective dust removal and cooling, thus suitable for wet or dry cutting.

The end use or application of the product is also influenced by the design of specific diamond blades. Continuous rim diamond blades typically have a thinner kerf width (the width of the diamond segment) when compared to segmented, which will result in a narrower cut, reducing heat from friction, and resulting in less loss of material. Diamond blade manufacturers also base diamond concentration, quality, and size on the typical usage for each type. Finer diamond grit is normally for harder materials (such as glazed tiles and granite), whereas coarser diamond grit is more suitable for softer materials (such as bricks). Choosing the incorrect type may not only result in chipping of the workpiece, but also reduced efficiency and higher cost per cut.
To ensure premium abrasives perform optimally, the machine being used, and its ‘power outage is to be considered. It is important to note that sufficient power tools still need to operate efficiently whilst under load, and that using an under-powered machine might increase the risk of the abrasives not fully reaching their full potential during an application.

As with any choice of product, the end result is key. Diamond blades are no different in this regard but staying informed of the latest technology and information around the various options within the market allows for a better-informed decision and ultimately a more successful application.

Contact your abrasive supplier should you enquire any additional information.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

Grinding refers to the process of removing unwanted material from a workpiece with applications ranging from rough snagging and dimensioning to the development of fine finishes on a broad range of materials including ferrous, non-ferrous, and non-metallic.

In most aspects, grinding is similar to milling, turning or other metal cutting operations, with the exception that grinding produces real value for a broad range of production processes.
Grinding wheels contain many thousands of hard and tough abrasive grains that cut away tiny chips upon application as it moves against the workpiece, overall, being a more gradual, less harsh method of machining that allows for a host of variables to be controlled with a degree of precision.

The main objective of any grinding application is to accomplish stock removal to get the raw workpiece into an intermediate size or degree of finish, where completed part tolerances and finish is usually of second concern.

Snagging, rough grinding, swing frame, portable grinding, and steel conditioning are some of the most popular stock removal applications that will achieve maximum material removal within the shortest possible timeframe.

In most instances, offhand applications are preferred as stock removal brings the workpiece to approximate dimensions. This application entails either the workpiece or grinder to be handheld, with the quality and quantity of grinding being left to the skill and stamina of the operator.

Snagging, used for cleaning and dimensioning castings after they have been poured and cooled removes gates, risers, stubs, fins, parting lines and accidental surface roughness.

For small enough castings that can be picked up and brought to the wheel, floor stand grinders are most popular, with the casting being handheld and cleaned as necessary.
Fettling on pedestal grinding machines entail manual guiding of the workpiece to the machine-primarily with lightweight workpieces.

Castings that are too large to be brought to the wheel, are machined on swing frame grinders, where the entire grinder is suspended on a jig over the work area and counterbalanced in order for the operator to press the wheel into the workpiece. For bulk and heavy castings, reciprocating grinding is the application of choice.

Our locally manufactured Andor grinding wheels not only offer the best in stock removal and longevity, but also reduce operator fatigue due to their high stock removal properties.

Another popular application used for heavy-duty jobs such as cleaning a casting or removing a large weld bead, is portable grinding where the grinder is powered by air, an electric motor or flexible shaft. In jobs where the grinding requirements are not as severe, raised hub wheels known as depressed -center wheels, are used. Applications include smoothing down flat and curved surfaces for painting and finishing, cleaning up weld lines, and smoothing corners and joints. A recessed wheel flange and the depressed centre wheel geometry facilitates a flush cut when cutting off runners and risers, leading to no additional smoothing requirements.

Mounted grinding wheels, more commonly known as mounted points, are small grinding wheels with special shapes, permanently mounted on a steel mandrel and commonly used in foundries for cleaning and polishing difficult to reach spaces on the workpiece. Thanks to their high cutting ability, diverse shapes, and dimensions, they offer effortless grinding. Superflex mounted points boast reduced vibration and high impact resistance on application with proven longevity and maximum safety making them perfect for deburring and chamfering.

Our locally manufactured Andor and Superflex grinding range offer excellent longevity, with competitive lead times, providing optimum results when it comes to stock removal and finish.
Apart from our wide assortment of mounted points, the Superflex range also carries a diverse selection of Tungsten Carbide Burrs that can be used for nearly all materials on a wide range of hand-operated pneumatic or electric machines, as well as industrial robots.

Apart from an extensive grinding range, we also offer a wide selection of cutting, coated, and non-woven abrasives. All our products are manufactured and tested in accordance with International OSA and ISO Standards.

Proudly South African based, Grinding Techniques is your perfect partner offering a total solution for all your abrasive needs in foundry applications. Contact one of our Application Specialists for a tailor made bonded and coated abrasive solution today.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

More Aluminium is produced each year than any other non-ferrous metal. The demand for Aluminium outweighs the supply offered in the market – this is evident in the current market price for Aluminium.

More Aluminium is produced each year than any other non-ferrous metal. The demand for Aluminium outweighs the supply offered in the market – this is evident in the current market price for Aluminium.

Being three times lighter than iron, highly resistant to corrosion, non-toxic, non-magnetic and an excellent conductor, it is no wonder that Aluminium is commonly referred to as the “Magic Metal”.

In 1807, Sir Humphrey Davy, the British scientist, established the existence of the element Aluminium. Being the third most abundant element in the earth’s crust, and occurring in most rocks, vegetation, soils etc., it is never found in its natural form as a pure metal. Aluminium is always locked in or combined with other elements.

Some Aluminium-compounds were used by man from the earliest of times. Primitive man-made pottery from clays containing hydrated Aluminium silicate and Aluminium salts used by the Egyptians in the preparation of dyes and medicines are just some examples.

Today Aluminium and its alloys are used in the fabrication of various items ranging from pressurised vessels, automotive components right to domestic use of foil for cooking and baking purposes. As wonderful as this sounds Aluminium is not the easiest metal to cut, grind or weld. Aluminium clogs easily and has a very low melting point, therefore very sensitive to heat input and prone to cracking in the heat affected zone if impurities are present. For this reason, correct welding procedures must be followed.

Identifying and using the correct abrasive product, whether it be for cutting, grinding, or blending, is core to the successful completion of any job. Besides the safety risk involved when using incorrect products and the potential harm this may cause, the effect on production lead times and final finish of parts or items being manufactured should also be considered.

Metal contamination is a major cause of component and weld failure and occur either through – direct contamination when using the incorrect abrasive products, cross contamination when using the same abrasives on multiple materials, or general contamination due to improper processing of materials in the work environment.

Direct contamination occurs when conventional cutting and grinding discs for steel are used for applications on Aluminium. Abrasive cutting and grinding discs, as well as coated abrasive flap discs, are designed and manufactured with various components that make up the final product. Some of these components like fiber reinforcing, are added to provide structure and support to the final product for strength and support to avoid breakage and damages when in use. Together with these components, other additives are also added into the mix to provide better results, usually by increasing the oxidative and corrosive effect in mild or carbon steels. However, such oxidative and corrosive compounds (Iron, Sulphur, and Chlorine) can cause major issues down the production line when used on Aluminium applications. If the work piece is not thoroughly cleaned of these compounds, should it become contaminated, subsequent welding processes will also be influenced and might cause welds not penetrating well, or porosity that will lead to weak welds that can cause catastrophic failures if not resolved.

To avoid cross contamination, care should be taken to avoid using abrasive products on mild or carbon steel, and then on Aluminium. Even though abrasive products are manufactured to be free of contaminants, unwanted Iron, Sulphur, and Chlorine compounds will be introduced when used on mild or carbon steel, which will be transferred to the Aluminum upon contact.

It needs to be noted that general workspace contamination can also contribute to contamination of various materials. Ideally, a floor layout should be planned in such a way that different material types are processed at opposite ends of a factory. This will ensure (to an extent) that swarf created during cutting, blending, or grinding operations will not come in contact with the Aluminum metals in the vicinity, thereby eliminating the possibility of contaminating materials.

Grinding Techniques locally manufactures specialised abrasive products free of contaminants which are perfectly suited to applications on Aluminum and Stainless Steels, like the Superflex Non-Ferrous range specifically manufactured for use on Aluminum.

From cutting, grinding to blending and polishing with our Superflex range, you can easily select a product suitable for your application. The Superflex Non-Ferrous Cutting and Grinding range provide easy clean cuts and stock removal free from contamination and without the concern of discs clogging. Our Premium Non-Ferrous Ceramic flap discs will provide the ultimate surface finish whilst keeping heat input to a minimum to avoid discoloring.

Grinding Techniques provides a solution driven service through its national network of branches, with a technical sales force geared to provide the best possible product solutions to optimize your production.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

The precision grinding industry is a vast and complex environment, that demands premium grinding media to deliver optimum performance and results.

With a range of different applications that require unique and specific results, several wheel shape derivatives are available.

Apart from the shape 1 straight wheel, used for conventional grinding applications, grinding wheels come in a range of other shapes and sizes including the well-known cup wheels.
Cup wheels can range from either a shape 6, which refers to a straight cup, shape 11, commonly known as a “flared” cup wheel, or type 2, which resembles a cup wheel with a ring shape – all very popular for grinding applications in industries, like toolroom, automotive, aircraft, engine components and wood working manufacturing.

Used for either producing new components, or regrinding and/ or resharpening of the different components after becoming blunt due to use, typical tools ground with shape 6, 11 and 12 cup wheels, include broaches, cutters, millers, reamers, drills, taps, and dies.

Most cup wheels are used for applications on fixed mechanical tool and cutter grinding machines, ranging in diameter size from 50mm up to 150mm, with a thickness starting from 10mm going up to 80mm.

Shape 6 and 11 cup wheels are usually manufactured with rim widths ranging from 4mm up to 13mm and are mainly manufactured with a vitrified bond, containing either Aluminum Oxide or Ceramic grains.

Choosing the appropriate grain when cup wheels are manufactured requires careful consideration of the material being ground, desired results as well as the amount of stock removal required.
During precision grinding applications, burning of the workpiece, is often a common challenge, which can be overcome by either using coolant during the application, or making use of a dressing application which can reduce, or eliminate this problem.

By creating chamfer on the rim with a handheld dressing stick, the cup wheel’s width will be thinned out, which will effectively decrease the contact surface area of the cup wheel to the workpiece, eliminating burn during application.

For grinding applications where a workpiece contains some heat sensitive materials, the use of a coolant during application should be considered as to minimise burning of the workpiece. In cases where workpieces consist only of heat sensitive metals, cup wheels manufactured from Ceramic grains should be considered due to its cool grinding properties.
Apart from delivering reduced heat during grinding applications, Ceramic grains are the most technologically advanced, offering self-sharpening properties with excellent stock removal in the shortest possible time. Effectively, this reduces overall downtime, as more components can be ground in between dressing applications, which, in the long run, not only reduces overall labor costs, but electricity, machine wear and tear, as well as consumable costs.

Also used in the manufacturing of cup grinding wheels, known as the purest grain, is White Aluminum Oxide, which with its high friability, is suitable for grinding heat sensitive steels, delivering optimum stock removal during application, without causing burn to the workpiece.

When it comes to applications on cemented carbide parts, Green Silicon Carbide grain will be the prerequisite, as it possesses both the extremely sharp grain characteristics, as well as the sought-after friable properties. Grinding wheels manufactured from Green Silicon Carbide usually range in grit sizes of 46 to 220, with a hardness grade ranging from H to N.
When manufacturing these wheels, the combination of grain and hardness are determined by the hardness of the workpiece to be ground, as well as the type of grinding application and required finish.

Grinding Techniques have been manufacturing ANDOR precision grinding abrasives locally since 1981 and specialise in custom grinding application solutions.

Whatever your abrasive requirement, our application specialists are ready and available to analyse your requirement and propose a cost-effective solution.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

The South African construction industry is multi-faceted and complex. With projects ranging from large scale green energy installations, to smaller at home DIY and general maintenance projects, it can be further classified into buildings, infrastructure and industrial construction. With the advancement of science and technology, we are seeing improved materials being utilised, as well as new composite and hybrid materials. According to various sources, the construction industry is projected to grow by 4% to 6% in the short term and by only 1% to 2% over the next 3 to 5 years.

The construction industry has come a long way from the Stone Age, where buildings were first built from wood, mud or rocks that were simply packed on top of each other. While these materials are still very popular in a much-updated guise (granted, that they have improved significantly in quality and usage), newer, more advanced techniques and materials are becoming much more prevalent. Hybrid materials are now being used in electronics, mechanics, energy conversion and storage as well as self-healing coatings for corrosion control paints. Hybrid construction methods also involve utilising multiple material types (such as wood, steel, glass) in new and unique ways. Composite materials provide several benefits (depending on the project requirement), such as a higher strength to weight ratio. Ceramic, carbon, and polymer composites are becoming very popular in the green energy generation, aircraft and aerospace, civil and general construction, as well as automotive industries.

Considering that the construction industry employs in the region of 8% of the South African workforce, the need for products offering “Value for Money” has become more important than ever before. The focus on occupational health and safety is now more than ever in the spotlight, which highlights the need for correct product selection to ensure a safe working environment.
The general lack of infrastructure projects, long process of contracts being approved and awarded, and pandemic induced factors means that more value is now required out of previously over-looked costs – consumables such as abrasives being an example. It is easy to find an abrasive product, but the question to ask is what kind of result is required.

Grinding Techniques, as a local manufacturer and supplier of premium abrasive solutions, is at the forefront of product development suited to these changing conditions. Constant testing and development are required to ensure that these new age materials are processed within the required tolerances and at an economical rate. Ceramic grains and super abrasives (diamond and CBN) are becoming the popular choice, but proper training and education is required to ensure that operators understand the differences, and correct, safe usages of these products. The loss of skilled workers over the years has seen a higher percentage of unskilled workers operating on construction projects. Grinding Techniques attempts to mitigate some of this risk by also offering training programs at retail and informal market levels.

Grinding Techniques manufactures true “Value for Money” abrasives that are tailored to optimise any construction project. The Superflex Professional range of cutting and grinding discs will help to reduce material wastage, reduce overall working time, and provide a better finished product. Superflex and Andor diamond saw blades are optimised for construction material applications. Ceramic coated abrasive products (such as sanding discs and belts) for Stainless Steels and other difficult to work materials, provide superior results.
The introduction of cordless Power tools on construction sites have brought about new dynamic in cutting and grinding, in that we now see a much higher percentage of cordless tools being used on construction sites, abrasive products also need to be optimised to retain the best possible balance of performance for these machines and this is where Grinding Techniques can assist you in selecting the correct abrasive product for your application.

We have, of late, seen a big shift towards renewable energy and energy saving projects in South Africa and across the world. Using abrasive products that reduce operating time, speed up processes and reduce waste will go a long way to assistin the greening process of the construction industry. It may only be a small part to play, but the sum of all small changes can and will add up to a major shift in the right direction.

Grinding Techniques is equipped to assist in every phase of a construction project to ensure that product selection is optimised to meet these goals.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

With so many grinding products available on the market, how does one know what the best choice will be – should I opt for a right-angle grinding disc, or will a flap disc suffice and what exactly is the difference between them and is it enough of a difference to make a difference?

A smooth, well finished metallic surface may be required for either aesthetic or functional reasons. Without a good start, one cannot expect to achieve a good finish and selecting the appropriate product will require some insight into the required end result, be it painted, polished or raw material look.

Considering that the go-to disc for stock removal has always been the rigid abrasive grinding disc, with the use of flap discs becoming more and more popular, one needs to first understand what an abrasive flap disc is. Unlike a traditional resin fiber disc, the abrasive flap disc is a single unit that contains its own backer. Abrasive flaps are arranged radially and in an overlapping format on the face of the backer and glued into place. Flap discs come in various shapes, sizes, and formats with distinctly different shapes.

Shape or Type 27, also known as flat, is best used for blending, smoothing, or finishing applications and suited more to flat surfaces being ideal for deburring and edge grinding applications. Shape or Type 29, commonly referred to as conical, works best for aggressive stock removal, where speed and cutting ability is required. The Type 29 provides a greater contact area with the angle of the disc for improved stock removal on flat surfaces.

Flap discs are manufactured from a range of different grains, each with its own properties suited to specific applications.

Alumina Oxide, red brown in colour, is the most cost-effective grain and usually reserved for light industrial or general-purpose jobs on soft metals and woods.

A more premium, high-tech grain, Zirconia, is blue green in colour and this grain self-sharpens as it wears away during application. Designed to provide high stock removal with fast cutting, this grain offers reduced heat generation with a cooler grind in the material.

Ceramic grains, offering the highest level of stock removal, and mostly red in colour have precision shaped grains that self-sharpen with a unique crystalline structure, which remains sharper and more effective over a longer time period, giving the product extensive longevity. Heat generation is further reduced due to the way that the grain breaks down during usage.

Grinding Techniques manufactures the Superflex flap discs using both Zirconia, and Ceramic grains, with the Premium range featuring a flap disc containing special anti-clogging properties within the ceramic grains specifically manufactured for non-ferrous metals.

Superflex Abrasive flap discs come in 40, 60, 80 and 120 grit sizes and different diameters to fit standard right-angle grinders. Coarser or finer grits are available on request. A coarser grit disc is used when a quicker removal rate is essential and surface finish is less important, whereas finer grits are usually reserved for blending, smoothing, and finishing operations, where surface finish is more important. They are typically used in the latter stages of the process.

Using flap discs carry a few benefits in comparison to conventional grinding discs.

As a flap disc provides a more controlled stock removal application with cooler cutting, less re-working of the piece is needed as discoloration is limited, even on heat sensitive materials where conventional grinding discs could potentially form fine hairline cracks resulting in damage on the piece, a cooler grind from the flap discs can avoid this to a great extent.

Two applications are possible with one product. An angle grinding disc has the tendency to create deep gouges due to the extremely aggressive design. A piece ground with an angle grinding disc will need to be retouched with a secondary product to improve the finish. With an abrasive flap disc, both stock removal and finishing can be done with the same product, at the same time. This reduces down time for disc changes, resulting in a reduction in overall contact time.

Operator fatigue is significantly reduced. Not only are abrasive flap discs substantially quieter than angle grinding discs, but they also create less vibration due to the lower pressure being used during application. Flap discs are lighter, which added to the lowered vibration, puts less strain on both operator and machine.

On the other hand, if you are only looking for fast stock removal and are not concerned by or requiring a smooth finish, then the traditional right-angle grinding disc may well be your best answer. Grinding discs are suitable for metal, non-ferrous and stone applications across a range of machine sizes. The main function of a grinding disc is fast material removal. Various industries utilize grinding discs successfully in their operations such as foundries and engineering shops. Depending on the application a range of grinding discs are available, from the standard Industrial range suitable for mild steels right to the Premium range suitable for high alloy and heat sensitive materials. As with flap discs, grinding discs are available in two shapes; a Shape or Type 27 for general grinding applications and a Shape or Type 28 which is a dome-shaped disc suitable for more aggressive stock removal at an angle which facilitates reduced operator fatigue as the disc design automatically provides the right approach or grinding angle without the need to manipulate the grinding machine.

To decide between a flap disc and a grinding disc one now needs to answer the following question – what does my end product need to look like? If your product needs to be painted, coated, polished and/or be provided raw with a good finish, then the abrasive flap disc is your best option, if you need fast material removal without the need for a smooth surface finish you may want to consider the grinding disc as an option.

In conclusion, the Superflex abrasive flap discs will provide fast, cool grinding regardless of the material. Coupled with the improvement in operator fatigue, the versatile flap disc does look to be the future product of choice.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

When bores and holes – straight or tapered need to be ground to specific tolerances and finishes, internal cylindrical grinding is the application of choice. One of the major challenges faced with this grinding application, is the restriction of coolant, as the grinding wheel is encapsulated by the workpiece.

This encapsulation effect increases the area where the grinding wheel is in contact with the workpiece to be significantly bigger compared to that of external cylindrical grinding. The specification of these wheels is usually a coarser grain size, softer hardness and a more open structure compared to wheels used for external cylindrical grinding.

Dependent on your application, there are different machines available for this specialised grinding application. With Universal Cylindrical, or Plain Internal grinders, the grinding wheel spindle rotates in a fixed position and the workpiece rotates and reciprocates along the grinding wheel.

When parts that are too large to rotate, need to be ground, the Internal Planetary grinder is the grinding machine of choice. During this process the grinding wheel spindle rotates and moves in a circular / planetary movement, with the workpiece not rotating, but reciprocating to attain traverse.

For internal centerless grinding, a Chuck-type Internal grinder is used which allows for the workpiece to rotate in a fixed position and the grinding wheel to rotate and reciprocate through the length of the hole or bore being ground.

Apart from the grinding wheel setup, selection, and, workpiece characteristics, other key points to consider include, the amount of stock to be removed, condition of the grinding machine, speed of both the grinding wheel, and workpiece as well as the use of coolant during the grinding application.

When selecting a suitable grinding wheel, one should be careful not to select a wheel too large in diameter for the workpiece to be ground. As this could not only result in the wheel blocking the bore, but also prohibit the grinding swarf from escaping, causing the grinding wheel to rub against the workpiece with no actual grinding application, ending in the workpiece heating and distorting. To counter this problem the general rule of thumb is to select a grinding wheel 66% to 75% of the size in ratio to the internal diameter being ground. This will allow free flow of coolant between the grinding wheel and workpiece.

During the grinding application, it is critical to ensure that there is sufficient volume of coolant with the correct direction and pressure into the contact zone, to prevent the workpiece from heating up, causing it to crack and warp, or clog as grinding swarf cannot be washed away.

Considering the type of material to be ground, and its hardness is equally important. With hardened materials, a grinding wheel with a finer grit size is more suitable, as it is easier for a finer grit to cut through the material than a coarser grain. Our Andor grinding wheels have a superior bonding system that l keeps the grain in place long enough to facilitate the grinding application and release the dull grain at the optimum point to expose new sharper grains. Due to this, we are able to manufacture wheels with specialty grains such as Sintered Aluminium Oxide which is known for having a higher stock removal rate and cooler grinding characteristics compared to other Aluminium Oxide grains. Using this type of grain significantly decreases the amount of time it takes to grind difficult materials, saving on both labor and electricity costs.

Further to this, the amount of stock removal, and the required finish should also be taken into account. A coarser grain wheel will remove material quicker, but not necessarily produce a very good finish, whereas a finer grain wheel will take longer to remove stock but will render a much finer finish.

With Grinding Techniques, it is easy to find the correct solution to your precision grinding application. Our Business Development team is able to assist with a premium basket offering of specialised abrasive solution to the precision grinding needs of your business.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

When precision in your surface grinding application is a non-negotiable, turn to Grinding Techniques for all your premium abrasive requirements. Surface grinding is an abrasive grinding process that makes use of various grinding media to grind either metallic or non-metallic workpieces to achieve a perfectly flat, or parallel surface with a specific surface finish. Types of grinding media used for this application, include grinding wheels, cup stones, and segments.

With different types of surface grinders available in the market, ranging from horizontal-spindle to vertical-spindle with reciprocating and or rotary table machines, to face grinding machines, it is essential to note that the type of grinding media should carefully be considered in order to provide the best result for each application.

Straight grinding wheels are typically used with horizontal-spindle reciprocating and or rotary table grinding machines where cup or cylinder grinding wheels and segments are more suited to vertical-spindle reciprocating and or rotary table grinding machines. When it comes to using Face grinding machines, cylinder grinding wheels and segments are the grinding media of choice.

Some of the machines are specifically designed for grinding intricate small workpieces, and others are for heavy machining of large workpieces such as forgings, castings, or long flat parts such as guillotine blades.

Most surface grinding machines make use of magnetic chucks to ensure that the workpiece is kept in place while the surface is ground to high precision. Every time a workpiece is ground and removed from the magnetic chuck or table it needs to be cleaned properly to ensure that no debris is left behind to obscure the new workpiece lying flat on the surface grinder’s table. Our Andor combination oil stone is the perfect tool for this application to ensure a perfectly smooth surface without any burrs.

When choosing your grinding media, certain factors need to be considered. Apart from the type of surface grinder, its power, speed, and condition, the workpiece’s properties also contribute to making the right choice e.g.  the material and hardness of the workpiece, the overall dimensions, the amount of stock removal required, and the desired finish are all important elements that play a fundamental role.

Another crucial factor, frequently overlooked, is the grinding fluid and its concentration as it is required to cool the workpiece during the grinding application, making sure the debris is washed away and the wheel is kept clean and open whilst in operation. Coolant that is not used with the correct percentage mixture or pH level can have severe consequences on the performance of the grinding wheel, either causing the wheel to clog up or not rendering the desired surface finish.

Once all the above factors have been considered, a grinding media can be specified.

Grain types are specifically designed for applications on various substrates ranging from mild steel, to abrasive resistant and extremely hard to ground materials. The correct combination of grain type, grain size, hardness, structure, and bond type will ensure that the workpiece is ground to the desired tolerance and finished in the shortest amount of time, saving on operational costs. Grinding media is manufactured from various abrasive grains, including white Aluminum oxide, which is the most pure and friable grain perfectly suited to hard metals where a cool grind is required with minimal burn. Ceramic grain is known for high stock removal rates on hardened materials and will produce an even cooler grind than Aluminum oxide. Producing class leading Andor surface grinding media, needs class leading bonding systems. These bonding systems, whether vitrified or resin, are extremely important as it is the glue that keeps everything in place. Even the best grinding wheel with the best possible grain on the market, needs a high-quality bonding system. Our proven Andor bonding systems coupled with ceramic grain works optimally to ensure the grain is kept in place long enough and is released by the bonding system just in time before it becomes too blunt, thereby producing the next sharp grain to continue with the grinding application. Not only does this ensure high stock removal rates, but it also ensures increased longevity throughout our Andor range. 

Our Andor premium surface grinding range is suited to all these applications and more. We are able to produce surface grinding wheels in sizes ranging from 150mm up to 750mm in outside diameter. All our grinding wheels are manufactured to OSA, ISO 9001, and EN quality standards, which ensure both safe and quality products.

Our Andor grinding media is finished with the latest finishing methods,  specifically designed to machine grinding wheels to the desired dimensions and international tolerances.

As a specialised abrasive manufacturer, we are able to assist with a custom precision grinding solution to any application. For more information, or assistance, contact our Business Development Team.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

The South African construction industry is multi-faceted and complex. With projects ranging from large scale green energy installations, to smaller at home DIY and general maintenance projects, it can be further classified into buildings, infrastructure and industrial construction. With the advancement of science and technology, we are seeing improved materials being utilised, as well as new composite and hybrid materials. According to various sources, the construction industry is projected to grow by 4% to 6% in the short term and by only 1% to 2% over the next 3 to 5 years.

The construction industry has come a long way from the Stone Age, where buildings were first built from wood, mud or rocks that were simply packed on top of each other. While these materials are still very popular in a much-updated guise (granted, that they have improved significantly in quality and usage), newer, more advanced techniques and materials are becoming much more prevalent. Hybrid materials are now being used in electronics, mechanics, energy conversion and storage as well as self-healing coatings for corrosion control paints. Hybrid construction methods also involve utilising multiple material types (such as wood, steel, glass) in new and unique ways. Composite materials provide several benefits (depending on the project requirement), such as a higher strength to weight ratio. Ceramic, carbon, and polymer composites are becoming very popular in the green energy generation, aircraft and aerospace, civil and general construction, as well as automotive industries.

Considering that the construction industry employs in the region of 8% of the South African workforce, the need for products offering “Value for Money” has become more important than ever before. The focus on occupational health and safety is now more than ever in the spotlight, which highlights the need for correct product selection to ensure a safe working environment.
The general lack of infrastructure projects, long process of contracts being approved and awarded, and pandemic induced factors means that more value is now required out of previously over-looked costs – consumables such as abrasives being an example. It is easy to find an abrasive product, but the question to ask is what kind of result is required.

Grinding Techniques, as a local manufacturer and supplier of premium abrasive solutions, is at the forefront of product development suited to these changing conditions. Constant testing and development are required to ensure that these new age materials are processed within the required tolerances and at an economical rate. Ceramic grains and super abrasives (diamond and CBN) are becoming the popular choice, but proper training and education is required to ensure that operators understand the differences, and correct, safe usages of these products. The loss of skilled workers over the years has seen a higher percentage of unskilled workers operating on construction projects. Grinding Techniques attempts to mitigate some of this risk by also offering training programs at retail and informal market levels.

Grinding Techniques manufactures true “Value for Money” abrasives that are tailored to optimise any construction project. The Superflex Professional range of cutting and grinding discs will help to reduce material wastage, reduce overall working time, and provide a better finished product. Superflex and Andor diamond saw blades are optimised for construction material applications. Ceramic coated abrasive products (such as sanding discs and belts) for Stainless Steels and other difficult to work materials, provide superior results.

The introduction of cordless Power tools on construction sites have brought about new dynamic in cutting and grinding, in that we now see a much higher percentage of cordless tools being used on construction sites, abrasive products also need to be optimised to retain the best possible balance of performance for these machines and this is where Grinding Techniques can assist you in selecting the correct abrasive product for your application.

We have, of late, seen a big shift towards renewable energy and energy saving projects in South Africa and across the world. Using abrasive products that reduce operating time, speed up processes and reduce waste will go a long way to assistin the greening process of the construction industry. It may only be a small part to play, but the sum of all small changes can and will add up to a major shift in the right direction.

Grinding Techniques is equipped to assist in every phase of a construction project to ensure that product selection is optimised to meet these goals.

Contact our Business Development team today for a premium solution to your construction application.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

In most foundries, grinding wheel costs can vary immensely per ton of castings poured.

This figure may vary from one foundry to another depending on the metal or alloy, size of casting, number and size of gates and risers, and on the type of equipment used—swing frame, floor stand or portable. Part of the cost involves wheels that may be used to notch or cut off gates and risers, but this article will concentrate on the wheels used for the snagging operation.

The grinding wheel can affect wheel costs as well as production rates. One major contributing factor to high grinding costs may be the use of the lowest priced grinding wheel obtainable. While this buying policy does offer the lowest wheel cost, it can ultimately be more expensive in both yearly purchases and labour costs. Furthermore, the cheapest wheel may also reflect inconsistent quality, which could result in a variation of grinding wheel performance from wheel to wheel and from order to order.

In order to extend longevity of the wheel with the main objective of a lower wheel cost, a wheel that is actually too hard for the application at hand is often used. The loss in the material removal rate and operator efficiency therefore offsets the costs of the wheel savings, as many tests have proved conclusively.

Using a too soft wheel, on the other hand, while contributing to a happier operator, will most certainly increase the total wheel consumption. Management may now ask how all these factors should be evaluated.

Some foundries measure grinding wheel efficiency in terms of the amount of metal removed versus the amount of grinding wheel used. Others may measure the grinding wheel cost per kg of metal removed. Both these methods may result in a two-dimensional view where a three-dimensional view with grinding time added will in most instances supply a better result.

In some instances, foundries do not realize how important wheel selection can be, relying only on operator opinion for the best wheel to use, without measuring wheel consumption or metal removed. Although this may seem like a simple solution, it is not likely to result in determining the efficient grinding wheel, or the lowest grinding cost. Operators most likely will tend to prefer a soft fast cutting wheel.

The above-mentioned approaches will most likely provide a very high ratio of metal removed to wheel wear resulting in a low production rate, or high productivity but with a relatively high wheel consumption. The ultimate aim is to strike a happy medium between rate of metal removed and wheel consumption.

The missing third dimension in these approaches to wheel efficiency and grinding costs is the time element. Labour and overhead costs in most cases contribute more than the wheel cost in determining the total grinding cost. The only accurate way to determine a fettling operation cost is to determine the weight of metal removed, weight of wheel used, and the total contact grinding time of the test. Contact time rather than total elapsed time is important as it is not subject to operator effort. Accurate measurement of the contact grinding time per casting or per test run is of utmost importance.

With contact grinding time readily available, accurate means of determining the weight of metal removed while grinding must also be obtained. The castings selected for test, after chipping and sorting of scrap, should be weighed before and after grinding. Larger castings should be weighed individually and small castings can be weighed by skid load. To ensure accurate grinding wheel cost information, the wheel should be weighed at full and then at stub diameter. The difference represents the weight of usable abrasive consumed during the test.

The castings selected for the test should all be of the same metal or alloy, and approximately the same size and shape. In reality, these last two conditions are not always possible. It is then that the value of determining contact time becomes even more relevant. It helps to balance out the effect of just such variables in the work pieces. Furthermore, when a wheel is used by more than one operator, using contact time in calculating the wheel efficiency and costs helps to eliminate variables in operator technique and operator opinion of a wheel.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

Sanders are one of the most frequently and extensively used power tools in Industrial workshops and DIY applications. Depending on how often they are used, it makes sense to choose a sander and abrasive product that suits you ergonomically. If you do a large variety of different types of sanding in your workshop for example surface sanding of large flat surfaces, edgework or molding and profile work, you will want to consider purchasing application specific sanders. Unless you are working in a high production environment using a sander for most of the day, a power sander will most likely last you for many years, if used with a quality abrasive product.

One of the most common challenges faced when using a sander is the visible scratch pattern left behind on the material that has not been eliminated through sanding. This can normally be clearly seen as the visible swirl pattern and milling marks when looking at the surface finish. These surface marks can be eliminated by using high quality application specific engineered abrasives that have consistent uniform grain patterns guaranteeing a more consistent and uniform scratch pattern on your workpiece surface. Selecting the correct sequence of abrasive products and grit sizes to create the desired surface finish is also of utmost importance when sanding with a power tool. When sanding with a progressively finer array of grit sizes will produce a much more constant surface finish which will also eliminate excessively deep swirl and scratch marks created when forcing the sander down to work harder and more aggressively. One must always remember the power tool’s weight should be sufficient for achieving the best sanding results. Excessive pressure whilst sanding creates more heat and dust which promotes clogging that severely affects the lifespan of you abrasive.

The most effective way to keep your surface dust free, is to use a power tool with a dust extractor. This will not only save time when it comes to applying the final finish, but will also ensure minimal dust on your workpiece surface that has to be cleared. Power tools with dust extraction prolongs the life of your abrasive as there will be significantly less clogging.
Random Orbital Sanders, Sheet Orbital Sanders, Detail Sanders and Belt Sanders are some of the most commonly used power sanders used in workshops of a hobbyist or DIYer. Of these, Random Orbital Sanders are with reason the most popular and most frequently used universal power tool due to their effective stock removal capabilities on large surfaces and their ability to deliver a smooth consistent finish.

Their backing pads move in an orbital motion while at the same time moving in an eccentric (off-center) orbit motion. The result is an irregular scratch pattern of swirl marks that can be easily and quickly removed by hand sanding before applying your final finish. There are models available in different strokes per revolution depending on the task at hand. Increasing sanding speed and applying a little more downward pressure will generally increase the cutting power and help to decrease your sanding time. Keeping these benefits in mind, it is important to remember that this will increase the severity of the swirl marks. These power tools are normally available in 125mm & 150mm backing pads with a Velcro clamping system, with discs that are quick and easy to mount and remove. These sanders also normally include a dust extraction bag or canister while some will have a port for connecting to a dust extractor, which will provide the most superior dust extraction.

Sheet Sanders are also called orbital sanders. They generally have a pad that takes a half or one third of a normal sandpaper sheet that is 230 x 280mm. The backing pad normally runs in one direction only, removing material more slowly than Random Orbital Sanders. As a result, the scratch pattern is very consistent. For the best results in wood sanding the sander should be moved in the same direction of the grain of the wood whilst sanding. Some of these sanders take a PSA (pressure sensitive adhesive) or Velcro sheet of paper, but most use metal clamps for attaching standard sandpaper sheets you can cut to size or purchase pre-cut. The shape of the backing pad enables them to sand close to the inside of corners, and their compact size makes them easy to control and ideal for sanding narrow surfaces such as table legs and drawer parts.

Detail Sanders come in a few configurations. These power tools are similar to sheet sanders but have triangular pads. Often also called Mouse Sanders, they are typically used by DIYers and hobby woodworkers. These power tools are ideal for reaching the tight hard to reach areas that are inaccessible to conventional sanders. The sandpaper used on these sanders is normally Velcro backed for quick and easy mounting and removal.

When removing large amounts of material very quickly, Belt Sanders are ideal and the most effective. This power tool is suitable for leveling wide and long surfaces or shaping larger curves. Being so universal, this remains a popular tool of choice for carpenters, flooring and cabinet installers, deck builders and the like. Sanding belts ranging from 60x400mm up to 110x610mm are available in various grit sizes and suit most belt sanders on the market.

Whatever your tool of choice, achieving the perfect finish is certainly made possible by using quality product options available in the market.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

Since the beginning of time, man found value in utilising various materials for the production of products related to self-sustainability. These materials evolved over time as technology and knowledge increased. From the humble beginnings of the copper age to the current highly sophisticated alloy age, casting of materials in usable forms and shapes remain a critical function.

The oldest metal casting known to man is believed to be a frog casting in Mesopotamia around 3200 BCE. It was the first cast product to show the forming of a mould prior to casting the molten metal.

The bronze age was the era where tin and copper were mixed in the melting process, the new metal was developed in Turkey, Iran and Iraq. It was however the Egyptians that really perfected this process to a fine art and produced many a weapon and other industrial appliances, dominating the bronze age.

With the iron age that followed, the Chinese mastered the art of metal casting and the systematic production of metals around 1000 BC. They managed to mass produce cast tools and farming equipment and the world’s first cannons and gunpowder. Along with the change in metal production came the changes in the agricultural, religious and cultural spectrums. Europe was only able to produce its first iron products 1000 years later.

After the iron age, the industrial age followed. This era was known as the age of the technical revolution. The demand for cast products was on the rise, and soon new machines were developed to keep up with mass production and demand. Products now casted would include machine components, engine components, rail equipment, equipment for the airline industry, and a vast array of other consumer goods.

Through the evolution of castings, the basics still remained the same; make the mould, melt the metal, cast, cool and finish off.

As the science of metallurgy has grown in the past three hundred years, so too has the methods used to machine and shape the relevant products. In ancient times, sand stone was used to “file” the relevant pieces. Eventually bigger grinding stones were mounted on hand turned machines to grind and sharpen products. Today we have Ceramicists and Bio-chemical Engineers developing bonding systems for new artificial abrasive minerals being created. Machines that run at speeds exceeding 100m/s and achieving metal removal rated higher than ever before, whilst maintaining form accuracy to literally micron tolerances. Alloys are now being developed to be harder than glass, but still maintain the toughness synonymous with steel and metal related products.

As the science of metallurgy has grown in the past three hundred years, so too has the methods used to machine and shape the relevant products. In ancient times, sand stone was used to “file” the relevant pieces. Eventually bigger grinding stones were mounted on hand turned machines to grind and sharpen products. Today we have Ceramicists and Bio-chemical Engineers developing bonding systems for new artificial abrasive minerals being created. Machines that run at speeds exceeding 100m/s and achieving metal removal rated higher than ever before,
whilst maintaining form accuracy to literally micron tolerances. Alloys are now being developed to be harder than glass, but still maintain the toughness synonymous with steel and metal related products.

Grinding Techniques – a Tyrolit Swarovski company is uniquely positioned to offer application-based solutions. With more than 138 combined years of experience in manufacturing abrasive tools, both Tyrolit and Grinding Techniques are able to offer a comprehensive range of specialised products.

The product range for a typical foundry application includes, but is not limited to:

– Hand Program (cutting and grinding discs)
– Vitrified Grinding Wheels & Segments (precision grinding wheels, bench grinding wheels, laboratory surface grinding wheels, toolroom wheels)
– Resin Bonded Wheels & Segments (swing-frame and pedestal grinding wheels)
– Mounted Points, and Bullnose Cones
– Tungsten Carbide Burrs
– Water and Cabinet Paper Sheets
– Flap Discs
– Fibre Discs
– No Centre Hole Discs
– Bobbin Sleeves – Also known as even-run or spiral bands
– Velcro Discs
– Grinding Belts
– Diamond & CBN Precision Grinding Wheels
– Diamond Discs
– Wire Wheels & Brushes

Our ability to manufacture custom made products to assist in optimising your fettling processes, is unrivalled in the industry today. Our understanding of metallurgy and equipment has propelled us to a become leading role player in the Foundry Industry. Our new innovative Premium Ceramic and Zirconia products are a prime example of market leading technology.

We offer an optimization service that allows for scientific comparison in all aspects of the grinding tool process from the material removal rate, to tool life comparisons and heat generation.

With one of the most comprehensive product ranges available in the Southern African market today, it is no wonder Grinding Techniques is the Industry partner of choice when it comes to the Foundry Industry.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.