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DIAMOND
TRADING COMPANY
INDUSTRIAL SIGHTHOLDER
Diamonds for Dressing Tools

Natural Diamonds are the most effective and efficient material for the
dressing of conventional grinding wheels. This is primarily true because of the
formation of natural diamond and the vast range of qualities available. Firstly,
the shape…the octahedron and dodecahedral structure with closed edges which
come together to form the strong points required for single point dressing
applications cannot be substituted competitively. Additionally, each diamond,
because of its natural geometry, can have as many as six usable points. Users
can opt for a range of tools from single use tools, with a stone having only one
useable point, to tools with stones which can be re-set to use all 6 of the
available points. The fact that it is a single crystal adds to the diamonds
structural integrity, giving continuous dressing action while maintaining
strength throughout its life. By choosing the correct size, quality, and number
of settable points, the end user will be able to dress the wheels properly and
obtain the best productivity at the lowest cost.
We can look at a few examples that will illustrate how the application
dictates which type of diamond should be used. For dressing thread grinders,
very sharp points and angles are required to enter the narrow grooves on the
wheel; clearly, the design of the tool calls for octahedral or even sharper
crystal type diamonds. This gives the operator the ability to dress very sharp
angles. For high production situations, the design will call for a high quality
stone that will hold up under repetitive use. For lower levels of productions,
the user may save on cost by using an appropriately chosen, lower priced stone.
For wheels made of materials tougher than standard abrasives, such as the
ceramic wheels used in some very tough applications, a dodecahedral shaped
diamond offers great strength and durability. There is more material surrounding
the point of a dodecahedral than the point of an octahedral, consequently
reducing the wear rates. The experienced diamond tool manufacturer understands
the need for a stone with significant durability and designs the tool based upon
this criterion. The number of usable points as well as the overall quality of
the stone will be a function of the expected workload.
There are other types of dressing tools that use multiple stone
configurations to obtain the advantage of natural diamond in dressing
applications. Elongated materials can be set up in various configurations for
specialized blade tools. Lower priced diamonds may be used in various types of
"cluster tools", even lower priced Congo cubes and rounds as well as
other low range materials are in demand for inexpensive "throw away"
type tooling.
All of this shows that there is great flexibility in natural diamond dressing
tools, from the standpoint of performance as well as cost. For dressing
applications, natural diamond has the characteristics that make it the preferred
material.
Diamonds for Form Tools For Truing and Dressing Applications
Although Polycrystalline diamonds as well as single crystal synthetics have
impacted this market, natural diamond remains a prominent player.
The tool designer who works with natural diamonds has a great variety of
formation, size and quality of natural diamonds from which to choose. Let us
look at the various natural formations available:
Triangles (Window and Pillow Type)
Long Stones (Flat and Full Bodied)
Egg Shapes (Flat and Full Bodied)
Round Shapes
Octahedron Shapes
Flat Shapes (Varying thickness)
Form dressers are designed for truing and dressing formed grinding wheels.
The tolerances of the tool are critical to obtain good manufacturing processes.
Ultra fine, clean diamonds are selected and polished by skilled diamond cutters
to precise tolerances for the most critical applications.
Medium quality diamonds may be chosen and cut to acceptable tolerances when
the design calls for less stringent specifications yet requiring a tool that
stands up under high production conditions. Lower quality diamonds are called
for in the design of typical, utility type tools. In these situations, cost of
the stone may be the over riding factor; however, the requirements of a
superabrasive tool can still be met with a quality product when the diamond
form, size and quality are correctly matched to the application.
Diamonds for Shape Tools for Cutting Applications

This area of application is clearly the one which has been most affected by
man made products and other new technologies. The effect has been positive in
that the availability of many types of superabrasive products has broadened the
field of usage and expanded the overall superabrasive cutting tool market
throughout the world.
PCD, PCBN, Single Crystal Synthetics and CVD products all have proven
effective in many new as well as traditional areas for cutting tool
applications. Nonetheless, manufacturers and users still find a broad range of
applications where natural diamond is the optimum product. The finished cutting
edges of PCD, PCBN and CVD products are inherently limited by the fact that they
are multi particle products. CVD products have, so far, also been limited in
their maximum thickness as well as limited by problems with adherence to the
substrate.
Both natural diamonds and single crystal synthetics are used where high
magnification, chip free cutting edges are required. Yet, the use of single
crystal synthetics may sometimes be questionable, as many end users have
determined that tool life may be inconsistent and that natural diamond, under
similar conditions, will outperform single crystal synthetics. The available
range of quality, size, shape, thickness and other characteristics found in
natural diamonds gives great flexibility and choice to the end user and the tool
designer. The "one quality, one price" of synthetics tends to limit
the end users choice.
Again, we see that in many applications, natural diamond is the product of
choice.
Diamond Dies for Drawing Wire

In every conceivable application from electronics to construction,
wiredrawing dies are the essential tools used to produce the billions of miles
of wire drawn throughout the world. For applications of drawing non-ferrous
metals, which require ultra fine finishes, diamonds are used as the cutting, or
drawing material. In particular, in today’s high tech world, ultra fine wires
are required in enormous quantities and the demand for diamond dies has exceeded
the expectations of many.
In fact, it was believed that the advent of PCD and single crystal synthetics
would eliminate the demand for natural diamond. Although single crystal
synthetics have been on the market for a few years now, and have entered some
niche markets, producers, end users and suppliers continue to have strong demand
for natural diamond dies. PCD has helped to expand the market for diamond dies
replacing carbide dies for larger sizes and improving productivity dramatically.
The continuing demand for natural diamond stones can be directly related to
better performance from naturals plus the great flexibility in pricing and
sizing that naturals provide. For obtaining high finish and for drawing fine
sizes, natural diamond continues to be the material of choice offering the
highest quality with the greatest productivity.
In some cases where PCD had made great in-roads, particularly for larger size
dies, natural diamonds have made a comeback. In certain applications, some
materials present in PCD have caused problems during the wire drawing process.
One example of this is "sparking", which can cause the lubricants to
ignite. This of course translates into down time and losses. The purity of
natural diamond and its single crystal structure are the important
characteristics allowing it to work unhindered in these applications. The
revival of demand for larger size natural die-stones is effectively the result
of definitive problems that arose in the use of alternative products.
For the making of natural diamond dies, the wire die manufacturer selects a
high quality diamond, flattens both sides with parallel faces, sets the stone in
a hard metal blank, drills through and polishes the center of the stone creating
the critical form and tolerances required by the wire manufacturer. Of course,
this is a serious over simplification of a complex and critical process. With
natural diamond dies, the producer will design the tool based on the size and
type of wire to be finished, enabling them to determine the dimensions of the
stone required. The diamond must be clean and uniform. Other characteristics
will be taken into account when the toolmaker is selecting the appropriate
diamond. This is individual to the company’s process and adds flexibility of
price according to the specifications of the application. With this, the die
maker can be highly competitive, tailoring products to meet the demands of their
customers. In turn, this enables the wire producer to meet the needs of industry
at the most cost-effective levels while ensuring high quality products.
We are confident that, for the wire die industry, natural diamond dies are
well suited to meet industry demands and will continue as an essential
superabrasive material for many years to come.
Diamonds for Drill Bits

Diamond drill bits are used in mineral and oil exploration, mining, and
construction. They are an excellent example of products that achieve results
possible only with superabrasives.
Whether searching for minerals and metals, or, tapping the great oil reserves
of the world, diamond bits are used to drill through the rugged earth
efficiently, reducing expensive downtime for drill rigs. In the construction
industry, where repetitive drilling of hard materials is commonplace, diamond
drill bits are normally used. Prior to the early 1980’s, natural diamond
stones were used in surface set bits for exploration and mining. These bits are
made by hand setting select diamonds in a mold, which is then filled with
powdered metal and heated to form the diamond bit. The bits are then used, and a
process started which involves reclaiming the natural diamond from used bits,
resetting the usable stones, and returning the bit to the user. The entire
process, from hand setting to reclaiming used bits, to the bookkeeping for
diamond reclamation, is an expensive process. Consequently, most hand set bits
were replaced with either PCD blanks or bits made with either natural or
synthetic mesh.
This is clearly an area where the usage of natural diamonds has been heavily
affected; however, natural diamonds continue to be used, although at a lower
level of consumption and price than in the days before alternative products were
available. The availability of inexpensive natural diamonds allows bit
manufacturers to exploit the potential of naturals by using naturals exclusively
or mixed with synthetic products. Thus, manufacturers can produce bits that
increase the efficiency of the drilling process.
In exploration and mining, the drilling conditions determine whether whole
natural stones or processed diamonds are used. In construction, impregnated bits
are made utilizing natural as well as synthetic mesh.
For the drill industry as a whole, the use of natural industrial diamond
continues to be important in achieving maximum productivity levels.
Grinding Wheels, Rotary Dressers, Impregnated Tools 
This group of tools is used in many types of engineering applications.
Natural diamond is often the raw material of choice when manufacturing various
types of impregnated tooling used in dresser applications. The strength of the
natural crystal and the cutting and friability properties of natural diamond,
provide the best characteristics in many of these applications. Consequently, in
manufacturing rotary dressers, natural diamonds, both processed and unprocessed,
are the main material used. Where additional strength is required, such as in
critical sections of the rotary dresser, natural diamond crystals are used to
give added strength to the wheels.
Natural diamond powders are used to obtain ultra fine finishes and for fine
grinding. The producers of these natural materials process, crush, categorize
and size each product into the many grades, which are used in today’s Superabrasives
industry.
Diamonds for Specialized Applications

Diamonds are intrinsic to the manufacture of certain types of high precision
tools and knives. The single crystal continuous structure, combined with the
purity, stability, strength and integrity of natural diamond provides the best
possible choice of material for use in new and evolving technology. Diamond
knives are used in surgical procedures and for slicing and sampling of various
materials, including human tissue. Diamond nozzles are used in water jets for
specialized cutting applications. In high-tech industries such as the
manufacture of fiber optic lines as well as certain precise etching
applications, no other material has the repeatable characteristics of natural
diamonds. Heat sinks, specialized diamond windows, guides, hardness testers, and
ultra precision cutting tools are but a few more of the specialized applications
where natural diamonds excel. If more attention and thought is applied to this
field, surely tool manufacturers will be able to extend and increase the range
of tools made with natural diamonds.
Natural diamond is a modern product for building the future!
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