Diamond tools from the Far East have an increasing presence in the catalogues of tool suppliers in the UK and Ireland. Can European producers fight back?

Whatever reluctance there might have been initially to sourcing diamond tooling in the Far East it has disappeared. Just about all diamond tool suppliers now source their grinder discs from Korea and other tools are beginning to make their way into the UK from Asia.

Fears about consistency and longevity are diminishing, although there are still concerns that buying from Chinese wholesalers can be a hit or miss experience with tools carrying the same brand (and sometimes it is the own-brand name of the Western buyer) being of such different quality that there are doubts about them coming from a single source.

The importers are becoming aware that they need to deal with a particular factory, rather than a middle man, and to build a relationship with their suppliers in order to obtain the consistent quality of product they want. Those relationships are developing and the products are improving.

Tool suppliers in the UK and Ireland are still offering European tools, especially for more sophisticated applications such as CNC workcentre and saw blades and, who knows, perhaps they always will – although Jason Barnard of Granite Tool Supplies (GTS) in Ashford, Kent, says: “If all our suppliers were as easy to deal with as the Koreans are, life would be a lot easier.” GTS buy most of their dry grinding pads from Korea and Jason says: “They have fantastic quality.”

He says Granite Tool Supplies are working towards own-branding everything they supply to establish their own GTS brand.

Harbro Supplies in Bishop Auckland have been buying diamond discs from the same supplier in Korea for a few years now. That supplier has helped Harbro develop their own brand products which Harbro say last well in use, remove stock quickly and are low price.

John Harland at MFT Stone in Alton, Hampshire, who has moved into a new warehouse and says both sales and profitability are still growing, also buys tools from Korea. But he says there is nothing to match the Italian Dokoyoh flexible discs from Ghines that he sells for speed of stock removal and longevity.

There are only three Dokoyoh discs – coarse, medium and fine. John describes them as “absolutely awesome” and because they are flexible they can be used for producing features such as soap dishes in worktops. However, at £95 for the fine disc and £125 for the coarse, these Italian discs are not cheap.

Fifteen years ago not many masons used diamond tools because they were too expensive – but then, not many masons worked granite at that time, either. The growth of both has gone hand-in-hand and it is no coincidence that the price of both has fallen, even more dramatically for tools than for granite.

The sales message for diamond tools has always been that they last longer, work quicker and produce a better finish than other abrasives. When they were a lot more expensive than other abrasives, masons remained unconvinced. Now, with the even lower prices offered by Far Eastern tools, more people are converting to diamond tools for more of their work all the time and it is difficult to see that trend changing.

The low prices from the far East are forcing European manufacturers to be even more inventive in trying to produce superior products that justify the extra purchase cost by reducing their customers’ manufacturing costs.

That can mean specialising on niche markets, an approach taken by Encore Diamonds in Endmoor, Cumbria, some of whose work has even been subject to the Official Secrets Act.

Encore’s Barry Whorrall believes that using their specially designed blades of various diameters for profiling is still the cheapest way to rough shape stone. When it comes to more intricate shapes, such as those required for the DeLank granite of the Princess Diana Memorial and the lettering of the Portland limestone Armed Forces Memorial, both produced by S McConnell & Sons in Northern Ireland using Encore diamond tools, Encore’s PCD, metal bond, vacuum brazed and electro plated products all have their advantages.

Speed of rotation and feed rates are critical, particularly on granite, when the plunge rate also has to be considered. Getting it right can extend the life of tools, which has been achieved in sandstone and limestone to give excellent cost effectiveness. Granite is more specialised and the life of the tools depends more on the hardness of the material.

Usually it is better to use a combination of metal bond, vacuum brazed and sometimes electro plated tools, depending on the required finish. PCD comes into its own when exact detail is required such as lettering and intricate shaping.

CNC machinery has opened up many opportunities for masonry companies and with imagination and design most projects are now possible. However, more imaginative applications can expose the inadequacies of some CNC machines, which no doubt explains the interest there has been in robot arms as they have become available for masonry work.

Stone has always been milled, traditionally with a heavy all-steel centre tool with hand-brazed segments designed for the material being worked. Because of the weight of the tool and general inaccuracy, it put great strain on the machines and their bearings.

Encore’s have sought to overcome the problem with lightweight plastics, making it possible to put a detachable metal ring on to the lightweight and reusable centre to give greater accuracy.

As always with diamond tools, it is still essential to design the bond and spacing of segments so that optimum performance can be achieved, not only for the material being calibrated but in relation to the user’s requirements and methods. Encore have received data back from customers who have operated these tool on passes as deep as 10-15mm with ease. Although the tool can operate at this high parameter, Encore recommend shallower passes and an increased transverse speed for optimal performance.

With the high level of accuracy and speed of take-off, many masons using Encore’s new calibrating wheel have found a multitude of applications for this high performance tool. The most obvious use is for reducing the thickness of granite splash backs.

The most popular diameters of the wheel are 350mm and 400mm with a width of either 25mm or 30mm, but they can be made to satisfy most requirements. Encore have produced wheels as large as 500mm diameter with a 40mm width, although consideration has to be given to the power and accuracy of the machine and any underhang that necessitates going for a larger diameter.

Ghines are looking for a technological advantage with their GTools range which they say applies state-of-the-art concepts of each diamond application technique according to the specific features required for the tool in each stone processing phase.

They achieve this with the latest techniques of sinterisation, vacuum-brazing, electroplating and vulcanization.

The result, they say, is that GTools do not have to be measured because they are constructed with such precision that they will always be the same dimensions – and just to make sure they are individually checked before being dispatched. The operator can replace the wheels with a new one and restart, confident that no adjustments are necessary.

GTools are available as rubber and sintex wheels that can be used separately or as a combination of both, using between four and seven grades depending on the material.

Marmoelettromeccanica, sold by Pisani through their outlets in London and Matlock, Derbyshire, are fighting back against low-price Korean polishing pads with flexible Turbopads. There are two patents covering the technology used – technology that Marmoelettromec-canica say not only halves the length of time it takes to go from grinding to finished polish but also means the pads will last four times longer than average.

Turbopads are rubberised diamond polishing pads attached with Velcro. They are for wet polishing granite, engineered stone and marble with angle grinders, and can achieve a high gloss finish, even on black granite, with just three grades after initial grinding with a 60-grit wheel.

Contributing to the longevity and quality of finish is a patented lubrication system.

Taking everything into account, Marmo-elettromeccanica say Turbopads offer the best price/quality ratio of any diamond tools available for angle grinders.

And that is just one of their ranges offering, they say, longer life and better performance.

Another is the SHS (Super High Speed) range of tools that Marmoelettromeccanica say can double your CNC machine’s productivity using patented technologies such as Frangistone and Long-life.

And Marmoelettromeccanica again offer guaranteed sizes so that a complete set of wheels will line up without having to adjust the machine.

Marmoelettromeccanica produce diamond tools for every stone application and are continually developing them – now in co-operation with the University La Sapienza of Rome, working with the academics there on the continuing development of new products and technologies.

The latest move of KGS in St Leonards on Sea in Sussex is a Centre-Locating-System (with a patent applied for) for diamond discs.

The system works by a simple male and female fitting on the diamond disc and back pad. The disc is quickly and securely attached to the back pad and perfectly centred every time. The CLS system is available on the Hybrid and Hybrid Super polishing ranges.

Glaston Bavelloni, an Italian company with their UK headquarters in Alfreston, Derbyshire, make CNC diamond tooling as well as workcentres and, again, guarantee consistency of the wheels to reduce set-up time.

The basic universal set of tools consists of four diamond wheels with a metal bond and polishing sets, called Bright. These consist of an elastic die and diamond abrasive made for three positions.

Bright was developed specifically to perform optimally on synthetic stones but is also ideal for natural stone and gives excellent results on absolute blacks and the most difficult granites.

For light stones Bright can be used on the first two positions only, while for the dark colours it should be used on all three positions.

Alternatively, Glaston Bavelloni propose for natural stones a couple of rigid wheels with a non-diamond abrasive, called Polistone, with 400 and 1000 grit size.

As well as the standard tools, there are many alternatives manufactured specifically for the type of material to be worked.