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WARNING:
Diamond
Drills & Diamond Drill Bits improperly used are dangerous.
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Before
Drilling
Visually
examine diamond drill for cracks or any other damage. Do not use if
damage is suspected. Damaged, incorrectly mounted, our misused
drills can be very dangerous to use. Always wear proper
safety equipment: Safety footwear, snug fitting clothing, safety
goggles, hearing and head protection, and proper respiratory
equipment. Make sure to check the diamond
drill for run out.
Checking
Diamond Drill/Bit Run Out
Run out will cause excess vibration when
your are drilling and effect the circumference (roundness) of your
hole. Instead of your hole being perfectly round, it will become
ellipse and uneven. Diamond Drill/Bit run out will also affect
tolerances you are able to achieve.
Every diamond drill is made to hold a specific tolerance and
run-out. When ordering diamond drills, make sure to indicate the
run-out and tolerance you need. To check for run out, use an
indicator specifically designed for this purpose.
Bring the indicator close to drill,
until its spring just touches the surface of the drill. The dial of
the indicator should indicate 0. Turn on your drilling machine,
holding the indicator firmly in place. The dial of your indicator
should remain at 0 while your drill is running (rotating). This
means you have no drill run out. If your indicator is greater than
zero, your drill is running out. Turn off your drilling machine, and
remount the drill. A black marker, is an alternative if you have
don’t have an indicator available.
Take a piece of paper or any thin piece
of material, measuring its thickness using a calliper or micrometer.
Place the material firmly against the drill. Holding the marker
firmly in place, remove material between drill and marker. Turn on
your drilling machine and observe drill rotation. If the marker
touches surface of the drill, there is too much drill run out. Turn
off drilling machine, and try again.
Another effective way of checking
drill run out, is rotate the drill head assembly (including the
water swivel adapter, if your drill has this feature) by hand. The
run out of the drill diamond section (the cutting/drilling edge)
will be indicated by the stem. A strong correlation exists between
the run out on the water swivel adapter and on the diamond drill—the
larger the run out on the water swivel adapter, the larger the run
out will be on the drill. If the run out is not properly indicated,
the drilling operation will not be accurate.
You should also
ensure that your drilling accessories are
properly held in the chuck.
If the drill or drilling device is not running true, loosen
the chuck of your drilling machine, turn it 90 degrees and run your
drill again. If this does not work, examine condition of your
equipment. Mount the drill on another drilling machine. Make
sure your drilling equipment is in proper condition to accomplish
your objectives. No matter how well the diamond drill is made,
it will not give you close tolerances if the shaft, or chuck of your
drilling equipment is misaligned or vibrates.
If for some
reason you feel there is a manufacturing defect, please return the
drill where it was purchased with a note explaining the difficulty.
Defective drills will be repaired or replaced. Drills improperly
used will be repaired or replaced at users expense.
Starting
to Drill a hole
Line up the
drill to the material being drilled. Clearly mark the insertion
point where you will start drilling.
Drill by quickly pressing and lifting the drill head. Moving the
drill up and down frequently during the drilling operation will
allow the coolant to cool the drill and flush out the material
debris formed while drilling. The colour of the water in the drilling
zone should be milky white. For some hobby applications, you
can consider using a pilot, which can easily be made from a piece of
wood. A pilot can reduce your drill slippage when starting the
hole. Place the pilot on the surface of the material being drilled,
with the pilot hole above the insertion point. Doing so will help
you maintain the drill in place as you start drilling. When making
contact with the material, tip the drill at a 45 degree angle. When
you have made a slight indentation, slowly bring the drill to a 15
degree angle, gradually straightening the drill as you penetrate
deeper into material. Drill by pressing and lifting the drilling
head, down and up frequently to allow water to flush out the
material debris formed while drilling and cool the drill at the same
time. Do not use extensive pressure.
If you find a piece of material debris is stuck inside the drill,
take it out before continuing to use.
Using a Pilot
Most pilots are used when drilling
existing holes (once the material has already been penetrated). The
RPM’s (revolutions per minute) are different than for the drill
itself. Often the pilot is worn out before the drill. When drilling
harder materials, the pilot should only be used when drilling
existing holes. This is not necessary for softer materials such as
limestone, sandstone, and fibreglass. You can start drilling with
drill and pilot right away. A pilot is a drill guide, usually made
from 2” x 4” piece of metal or wood.
ADVANTAGES
of using a pilot with your drill:
- Centre the outside hole
- Make
sure the drill will not walk
- Keep the drill as rigid as
possible
Securing your material while
drilling
It is
extremely important that the part you are drilling is clamped down
and hold securely in place. So material does not move, if material
does move while drilling it may break the diamond section of your
drill. A clamp should be used for this purpose.
Do not hold the part (material) with your
hands. Doing so is dangerous, and your material will
chip. For drilling thinner materials and substrates consider using
heavy duty double sided tape to firmly hold your material in place.
Drilling
Speeds
To maximize the life of your drill and
minimize material damage, it is important to run your drills at the
proper drill speed and pressure. Drilling speeds vary with diameter
of diamond drill, diamond mesh size, coolant being used, diamond
bond type and hardness, as well as material hardness. Micro Diamond
Drills from .001” required drilling speeds as high as 150,000Excluding RPM.
Whereas very large diamond drills 48” diameter require drilling
speeds as low as 3 RPM’s.
Below is a chart of Recommended RPM's
(speeds) in correlation to diamond drill/bit diameter. Please
note this chart is for reference purpose only to be used as starting
point only. RPM's will vary with material being drilled,
material hardness, density, geometry, drilling depth, environment,
and operator objectives.
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DIAMETER |
RECOMMENDED
RPM'S |
| .001” to .004” |
300,000 to 450,000 |
| .005” to .015” |
65,000 to 150,00 |
| .016” to .030” |
30,00 to 65,000 |
| .031” to .090” |
9,000 to 30,000 |
| 1/8” (3.18mm) |
2,500 |
| 3/16” (4.76mm) |
2,250 |
| ¼” (6.35mm) |
2,000 |
| 5/16” (7.94mm) |
1,500 |
| 3/8” (5.52mm) |
1,250 |
| 7/16” (11.1mm) |
1,000 |
| ½” (12.7mm) |
950 |
| 9/16" (14.28mm) |
925 |
| 5/8" (15.87mm) |
875 |
| 2/3" (16.93mm) |
850 |
| 11/16" (17.46mm) |
850 |
| 3/4" (19.05mm) |
825 |
| 7/8" (22.22mm) |
775 |
| 1.0" (25.4mm) |
700 |
| 1-1/8" (28.57mm) |
675 |
| 1-1/4" (1-1/4mm) |
650 |
| 1-3/8" (34.92mm) |
600 |
| 1-1/2" (38.10mm) |
550 |
| 1-5/8" (41.27mm) |
550 |
| 1-3/4" (44.45mm) |
550 |
| 2.00" (50.80mm) |
525 |
| 2-1/4" (57.15mm) |
500 |
| 2-1/2"
(63.50mm) |
475 |
| 3.00" (76.20mm) |
450 |
| 3-1/2"
(88.90mm) |
425 |
| 4.00"
(101.60mm) |
400 |
| 6.00"
(152.40mm) |
300 |
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Soft, abrasive materials can typically handle
higher drilling speeds, while hard, dense materials require
much slower speeds. Faster
drilling might appear to increase your
production efficiency, but the trade-off is a
significant increase in friction and heat, which
considerably reduces the drill life and increases the risk
of heat fractures and breakage in the material being
drilled.
Meaning if a diamond core drill develops dark “burn”
marks at the diamond section, the drill
is being used is too fast or the amount of pressure is too great.
Reduce drilling speed or adjust pressure accordingly. It is
generally recommended that you use a drill as fast as it will drill
freely.
Drilling with Coolant
Coolant should always be used to cool and lubricate the
drill. The most frequent cause of diamond drill damage is drilling
without enough coolant. Never run a diamond drill dry—coolant should
always be used to cool and lubricate the drill and to flush out
abrasive particles formed while drilling. When used without
coolant diamonds turn into carbon under high temperature.
This is known as the reverse osmosis process. Water is the most
frequently used coolant because it typically provides excellent
Proformance at a minimal cost.
Water is a true organic coolant, which does not leave the
material being machined oily, greasy, or contaminated. City water
with 90 psi or running water is usually used for drilling.
Other types
of coolant include:
synthetic water soluble coolants, mineral oils, other oils, and
on some applications cold or compressed air. If you are planning
to use water as a coolant, check with the drill manufacturer to find
out what water pressure is required and if any additives are
recommended. (Note that using additives will require a circulating
system to ensure that the right ratio is maintained between your
additive and coolant.)
The coolant
must also be applied in the right place to ensure that it properly
cools the drill and the material being drilled. The coolant should
be directed so that the full flow is at the point of contact between
the drill and the material, facing the same direction as the
rotation of the drill. When drilling on a vertical surface (not
recommended for advanced ceramic materials), use a squirt bottle or
small cup of water to continuously pour water onto the drilling
zone. Make sure enough coolant is reaching the drill. Alternatively,
you can submerge the material into a shallow tub of coolant so that
the coolant just barely covers the material surface. If
coolants cannot be used, consider using air to cool your
diamond drills. If air cannot be used, a resin bond or electroplated
(nickel bonded) diamond drill may be a solution.
Never run a diamond
drill dry. Severe damage
will result. Coolants do 3 things:
a.) cool
drill and material being drilled
b.) clean
out abrasive particles formed while drilling
c.) provide
lubrication to keep drilling edge clean
When
drilling in harder materials such as granite, agate, quartz,
porcelain, or very hard materials like sapphire and alumina, it is
important to have lots of coolant. Running water through the
centre
of your drills, is the best way for drilling these materials. This
can best be accomplished by using a
water
swivel adapter. Doing so, you will have constant water pressure
following through the centre of your drill. Which you will be able
to regulate. All diamond drills with female collet (thread) can
be used with a water swivel adapter. Such as
sintered (metal bond) diamond drills or
Electroplated Thin Wall diamond drills . If you are using
electroplated (nickel bond) core drills, you will need to drill
with a small amount of water constantly running over the diamond
core drill and bore hole by using something like a garden hose.
For some
applications, you may want to use an additive with your coolant. If
you Fenide to go this route, you will need a circulating system
and the right ratio between your additive and coolant.
Coolant Usage Suggestions &
Recommendations:
Drilling
on a horizontal surface
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use a
squirt bottle or even a small cup of water to continuously pour
water onto the drilling zone. Observe hole to make sure enough
lubrication is reaching the drill.
-
submerge the material into a tub of water. So water just
touches material surface.
Drilling
on a vertical surface
-
consider using a water swivel adapter to provide coolant through
the centre of your drills.
Water swivel adapters provide the most efficient and
effective method of coolant.
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should
you find yourself in a situation where a water swivel adapter
cannot be used, use a garden type of hose which can be easily
obtained from any hardware store.
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if this
is not possible, use a squirt bottle to provide coolant to your
drilling zone.
Water Swivel Adapters
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Provide coolant through the centre of the diamond core
drill. Water Swivel adapter cools both diamond core drill
and material in zone of drilling. Water swivel adapters come
with a valve for adjustable water flow. On Average, diamond
drills used with water swivel adapters will last
40% to 75% longer. |
Diamond
Core Drills used with water swivel adapter will not overheat
material and prevent cracks that occasionally arise from drilling.
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WARNING:
Drilling
generates dust. Excessive airborne particles may cause
irritation to eyes, skin and respiratory tract. To avoid
breathing impairment always employ dust controls and
protection suitable to the material being drilled.
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Best and most efficient way of
drilling ultra hard materials
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Best & most efficient way to obtain
(extract) core samples
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Improve surface finish quality and
reduce material chipping
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Increase Diamond Drill Life 40% to
75%
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Increase Drilling Speed & Feed Rate
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Prevent micro cracks that
occasionally arise from heat generated while drillings
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Preserve material true micro
structure
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Obtain More Consistent overall
Proformance
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Optimize your Diamond Drilling
Operation to ultimate point of efficiency
Coolant pressure
You will find the more pressure you have
on your coolant, usually the better your drilling results will be.
Strong coolant pressure will wash out material debris (centre plugs)
stuck in centre of your drill. Centre plugs restrict coolant flow to
centre of drill and prevent coolant from reaching the diamond
section. Your drill swill start to drill dry, significantly reducing
your drill life, material surface finish, and deteriorating overall
Performance. Centre plugs preventing water reaching the diamond
section, are behind 90% of all drill wreckage.
Using Coolant through centre of your
drills
When drilling with diamond drills, the
proper use of coolant
is important for two reasons.
Minimize Drill & Material Overheating
Frictional heat produced at the working
face of diamond tip must be disposed immediately. Otherwise the
diamond become rapidly damaged by oxidation and graphitization.
Excessive heat generated while drilling will also damage the metal
matrix holding the diamonds in place.
Insure Drilling Consistency
Debris generated while drilling should
be removed as soon as they are produced. When this drilling debris
is not removed rapidly, diamond wear increases through abrasion
caused by the presence of excessive coarse stone fragments.
Water is the most common coolant used
for many drilling applications. It is always a good idea to pump an
adequate supply of water or coolant through the centre of the drill.
So that an uninterrupted flow is maintained flushing across the
working surface of the drill diamond section. In this way diamonds
and the metal matrix are both kept sufficiently cool. And material
debris is removed as soon as it is produced. This is the
most optimum condition for your
drill.
Reduce Friction between material and
drill
Water/coolant also penetrates the
micro-cracks witch are generated upon impact of material and diamond
drill. Under ideal conditions, the material will absorb
water/coolant, hence becoming completely saturated with
water/coolant. In this state the material is weaker and more easily
drillable.
The coolant surface tension also plays
an important part in the drilling operation. Usually the lower the
surface tension, the easier it is for the coolant to enter the micro
cracks. Coolant with a lower surface tension also wets the diamonds
more easily. Most users find that by lowering the surface tension of
their coolant, resulted in better cooling (wetting) of their
diamond, and more effective overall cooling. Lower surface tension
also improves material debris lubrication, promoting efficient
removal.
Applying
Pressure to Drill
It is also
very important to apply the right amount of pressure during
drilling. Use light to medium pressure, gradually feeding the drill
into the material, until the drilling begins to progress at its own
speed. Increasing pressure on the drill will do little to reduce the
time it takes you to complete a hole, but it will cause your drill
to overload and overheat, which will lead to excessive wear on the
drill and defects in the material being drilled.
When you
are drilling completely through a piece of material and the hole is
near completion, reduce the drill pressure considerably to minimize
chipping of the material. Never force a
diamond drill. Apply even
pressure until the drill and material just touch. Since the drill
and material surface are not perfectly even (symmetric) to each
other, this lets the drill surface become sharper and adjust to the
surface of material. If a diamond core drill develops dark “burn”
marks at the diamond section, the drill speed is probably too high
or the amount of pressure is too great. Reduce the drilling speed or
pressure accordingly.
Using
Submerged Pressure
Using
frequent up and down motion when drilling will help propel coolant
deeper into the hole being drilled. It is highly recommended that
drilling should be done in even intervals. Drilling for about 30
seconds, lift diamond drill up from drilling zone to let it cool in
air and diamond and coolant reach further into the drilling zone.
Following this technique will reduce pre-mature and uneven diamond
drill wear and avoid diamond drill/bit wreckage.
Balancing Drilling Speed,
Pressure and Coolant
Drilling
speeds are affected by the hardness and abrasiveness of the
material, age and condition of equipment, pressure and coolant.
Experience with a specific material and applications allows the
operator to develop the right drilling process for their particular
application, and taking into account all of the factors discussed
above. New users, who are just beginning to drill with diamond
drills, are better off starting to drill at low speeds, low pressure
and with a large amount of coolant. Until they are able to build
their experience using a specific diamond drill, set up, and
application. Doing so will minimize the risk of diamond drill and
material damage.
Drilling Depth
When
drilling with core drills in material over 1/2" thick, it is
recommended to drill to a depth of about 1/2", then remove material
debris with a chisel or screwdriver before continuing to drill. If
you are using a water swivel adapter, increase the water pressure
until, the debris stuck inside is flushed out. If you are drilling a
thick piece of material, repeat this process several
times. Continuing to drill without removing material debris stuck in
the centre will cause the drill to burn up, since enough coolant is
unable to reach the drill.
Applications
require drilling depth of not more than 1”. Applications requiring
you to drill over 1” should be tread in a different way. We
recommend running coolants from multiple directions. Through drill
centre, from side of drill, as well as drilling submerged in
coolant. This will insure maximum amount of coolant and lubrication
reaching your drilling zone. Apply more pressure and reduce speed
the deeper you penetrate into your material. Lift drill up, after
every inch drilling into your material, letting the drill cool and
coolant reach deeper into your hole. Carefully examine the diamond
tip condition, making sure its round, and not overheated.
Your maximum
drilling depth will also be limited by spindle travel. The distance
your drilling equipment can move in an upward and downward motion
before touching the surface of your material. Make sure to take this
into consideration when ordering diamond drills.
Extending Drilling Depth
Diamond
Drills usually have a drilling depth of about 2" to 2-3/4", with the
shaft being 1" to 2" long and the diamond depth (diamond section)
being about 8mm. When drilling deep holes, beyond the diamond drill
depth, the drill chuck may come into contact with the surface of the
material being drilled. A drill tube extension can be used to
lengthen the drill drilling depth. Various sized tubes (core
drill) extensions can be purchased at most hardware stores,
building, contractor, and do-it-yourself supply centres.
Applications requiring you to drill over 1" (25.4mm) should be tread
in a different way. We recommend running coolants from
multiple directions. Through drill centre, from side of drill, as
well as drilling submerged in coolant. This will insure maximum
amount of coolant and lubrication reaching your drilling zone.
Running high pressure of coolant through centre of your diamond
drill/bit by using a
water swivel adapter is highly recommended for drilling
material over 1" (25.4mm) Thick. Longer Drilling depths may require
drilling in several steps and using more than one diamond core drill
/ diamond drill bit.
Small
Diameter Drills
 Small
diameter diamond drills must be used at significantly higher speeds
than larger size drills. It has been found that higher
Revolutions Per Minute (Ram's) improve surface finish and overall
drilling Performance. Ram's for diamond solid drills .001” to
2.5mm (without centre hole for coolant flow capabilities) range from
9,000 to 450,000. Drilling equipment that can accommodate these
speeds include: high speed air spindles, hand held drills, and other
specialty micro drilling equipment. High speed air spindles can run
up to 450,000 RPM, hand held drilling machines to 35,000 RPM, and
specialty micro drilling equipment up to 25,000 RPM. All diamond
solid drills and diamond micro drills must be used with coolant. We
recommend either drilling submerged in coolant, or applying air as
coolant (in some cases), if other liquid coolant types cannot be
used.
Smaller
size diamond core drills 1.6mm to ½” (mounted on a collet with
thread and designed to run coolant through centre of drill) must run
with high pressure of coolant 45 PSI through centre of drill. This
is the key successful drilling very hard materials. Drilling
submerged in coolant is not recommend. Once the core (material
debris) becomes stuck inside the drill, coolant is blocked off from
the drilling zone, and the drill can no longer be used.
It is very
important that you periodically check the inside of the drill for
material clog up. If you spot the material core becoming clogged
up, flush out this debris using coolant pressure from a water swivel
adapter or other coolant source. Continue drilling only after the
debris has been removed. We recommend that you use diamond core
drills 1/2" and above on a drill press.
Dressing
Diamond Drills
Most
Diamond Drills can be dressed (retrued) several times. Usually the
wear on the diamond drill depth takes place on the drill core and
diamond section, as well as wall thickness. A diamond drill can be
returned by facing off the drill depth with a SiC wheel to the point
where the wall thickness is standard.
Retrueing (dressing) causes diamonds to be pulled out from
the drill diamond section (diamond tip). For this reason, great care
should be taken to reduce this effect. We suggest exposing the
diamond section with a Al203 stick after retrueing. This is a very
simple operation: just drill into the
dressing stick a few times.
Diamond core
drills may require dressing. Dressing clears the bottom of the drill
from “glaze” and exposes new sharp diamond on end or bottom the
diamond core drill. It is the bottom of the drill that does all the
cutting, not sides of the drill. When the drill is “glazed” an
excessive amount of pressure is required to drill. Excessive
chipping or breakout may result in the work piece. DO NOT DRESS
SIDES OF THE DRILL
HOW TO DRESS
Start by drilling
in approximately ¼” (6mm) deep into the stick, this should be done
two to three times (when drill is seriously glazed over, it may be
required to drill as many as 20 times into this dressing stick to
correct the problem). MAKE SURE TO KEEP COOLANT FLOWING. Coolant
should flow over the dressing stick. Dressing without coolant is
worse than not dressing at all.
WHEN TO DRESS:
There is no easy,
straightforward answer to this question. Conditions such as material
being drilled, depth of hole, drilling conditions, all play a factor
on when a diamond drill should be dressed. Here a few tips in
detecting when your diamond drill should be dressed:
a.)
Sound –
when a diamond drill is sharp and in good cutting condition, the
drill will give off a “hissing” sound. When the drill requires
dressing, a :shrill screech” sound will be heard. When this sound is
heard, stop drilling and dress the diamond drill.
b.)
Pressure
– when using a diamond drill, pressure needed to drills also a good
indication of when to dress. The normal amount of pressure required
to drill a piece of glass is 23 to 30 pounds as an example. If after
drilling for a while, the drill requires additional pressure to
drill, this would be a good time to dress the drill.
c.)
Time Cycle
– the indicator is much the same as a pressure top-off. If drilling
cycle becomes excessive, stop drilling and dress the drill.
Diamond Drill Maintenance
Proper
diamond drill care and maintenance is very important for optimum
drilling Proformance. Maintaining the diamond section shape and
rigidity is important to prevent the drill from loosing its
sharpness and roundness. Make sure to repeatedly dress and retrue
the drills diamond section to rexpose new diamonds. If you see the
diamond drill has lost its shape or rigidity, send it back to the
manufacturer to be retrued.
Importance of following proper mounting, dressing, and coolant
techniques
Sintered (metal bond) Diamond core
drill, 5/16” in diameter was used to drill 0.070” thick alumina
substrate mounted on double sided tape.
Hole # 1: Diamond
Drill was not dressed before use and also shows signs of significant
run out. Hole is out of round and shows signs of diamond drill
hitting (hammering) surface of material, before making indentation.
Hole # 2: Diamond
Drill was properly mounted and checked for concentricity. However,
diamond drill was still not dressed before use.
Hole # 3: All proper diamond
drilling procedures were followed. Diamond Drill was properly
dressed and is running concentric. |
Hand held with stand 
