Examining Diamond Sharpening Whetstones

Transcription

Examining Diamond Sharpening Whetstones
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Examining Diamond
Sharpening Whetstones
D
iamond sharpening whetstones are now
well established as a medium for bringing a sharp edge to tooling in a very short
space of time. Even the staunch traditionalist has
come to accept that this medium has huge benefits over conventional means of sharpening, such
as retaining flatness, speed of cut and (in certain
cases) long durability.
However, there is now a quagmire of diamond
products in the market place which has resulted
in much confusion to end users in deciding what
best suits their needs. As in any range, there is a
huge variation of quality, appearance and most
importantly price. As a
golden rule remember the
following, “You get what
you pay for.” There are
good reasons why you
can buy three grades of 6"
stones in a set from as little as £15.00 and yet
another manufacturer will retail a single 6" stone
at £55.00.
Over the next few issues of “Yandle’s Wood
Club magazine” I will try to cover the reasons
behind these differences, answer the major questions that are usually raised and also try to
explain things in plain English!
CONSTRUCTION
This is the major factor to the reasons of variation of quality and price.
There are two basic means of construction,
impregnated or electro-plated.
● Impregnated: In basic terms it is like a layer
of diamond being spread onto a covering
of glue, cheap to produce and as good as
the glue!
● Electro-plated: The base material is submerged into a tank of Diamond in a Nickel
solution which is then electro-plated onto the surface. The Nickel
grows around the Diamond locking
it in place with two thirds submerged and one third exposed as
the sharpening medium.
There are two types of Diamond
used: Polycrystalline
or Monocrystalline.
● Polycrystalline
Diamond is a fragmented compound,
which shatters off a
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new face after each sharpening, thus it wears
away rapidly. Cheap to use in construction at
the expense of durability.
best guideline is the price and purchase a reputable make. Remember, you get what you
pay for.
● Monocrystalline
Diamond is a single structure that
does not break
with use. It is
strong and has an
exceptional lifespan. (The Trend range of Diamond products
use a Diamond called Element 6 – previously
known as Debeers. To achieve precision products you must use the premium components.)
SHOULD YOU USE A LUBRICANT?
Yes. If you use a Diamond Whetstone dry then
this will result in clogging up the abrasive surface. The swarf has to go somewhere!
There are two types of surface produced, Matrix
(holes) or a continual surface.
● Matrix (holes): i.e. DMT (USA) / various
cheaper Eastern imported variations.
● Continual Surface: i.e. Trend (Made in UK
– recent winners of The Engineering
Excellence Award 2006) / Atoma / Eze-lap
On balance, in my opinion, there are added benefits for continual Diamond surfaces,
1 50% more Diamond per square inch.
2 A “smooth feel of cut” – the Matrix system
sometimes gives a “lumpy feel of cut”.
3 No snagging when sharpening smaller or
pointed tooling. Sharpening chisels or smaller
on the Matrix system results in catching in
the holes.
Therefore Diamond products vary greatly in
quality and price between the cheaper end of the
market, impregnated / Polycrystalline to electroplated / Monocrystalline.
HOW DO YOU KNOW WHICH ONE
IS WHICH?
Quality manufacturers usually will have the
details of construction on the packaging; however, the cheaper ranges will not, so therefore, the
WHAT IS THE BEST LUBRICANT?
Though companies such as DMT have always
stated that you can use water as a lubricant, over
the past few years there has been a significant
move towards using specialised products. Trend
introduced four years ago, a lapping fluid (petroleum based) which has been used in
the Engineering Industry for more
than thirty years. It was specifically
designed and produced for use on
Diamond abrasive products. Trend
regard this product so highly that
they now offer a five year guarantee
on all of their range of Diamond
stones when using this lapping
fluid. It has already been widely
recognised in the press and Trade
journals as being the best lubricant
to use. An Atomiser spray top ensures that the
product, in normal use, can quite easily last in
excess of a year.
WHY SHOULD I USE A LAPPING FLUID
WHEN WATER IS FREE?
To prevent rusting problems. Remember that
quality Diamond Whetstones are electro-plated
using Nickel. Nickel is porous. Any waterbased lubricant can result in the threat of rust
blemishes. You will get long life from a quality
Whetstone if you look after it. The lapping fluid
is petroleum based so if, by mistake, you leave
any fluid on your whetstone it will evaporate
within 15-20 minutes.
Used
with water
Used with
lapping fluid
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CAN I USE WD40 OR
SOMETHING SIMILAR?
It is too thick, you will “skate” over the Diamond
surface on the quality products.
EXAMPLE
The Trend double sided bench stones are finished
off to a precision flatness of +/- 0.0005". On the
fine side they use Diamond which is 11 micron
(a human hair cut in half is approx 50-60
micron). Only the top third of the Diamond is
exposed, therefore the sharpening abrasion is
one third of 11 micron…WD 40 is too thick !
This works out more practical as well as finding
that you can prolong the life of your cutters by up
to 10 times. Follow these steps:
● Always sharpen your cutter on its flat face,
never touch the profile side otherwise you
will change the shape of the cutter.
*
*
A useful reference guide to all sharpening
with Diamond products is the Trend DVD
on sharpening available from Yandals
shop. Complete with live demonstrations &
practical advice.
A Guide to Router, Saw Blade
and Spindle Knife Sharpening
FLAT SIDE OF THE ROUTER
● Count the amount of strokes on one
face and the repeat on the other so
that you keep it in balance (removing the
same amount of material from either edge).
Featuring the Trend double sided
(Fine & Coarse) Credit Card Whetstone.
Regular maintenance/sharpening to any tooling
ensures that you are able to maintain a sharp
edge without too many problems. A little bit and
often is the key. Router cutters, either H.S.S. or
carbide, can be sharpened in as little as three or
four strokes using Diamond abrasive products.
Remember, compared to Diamond, Tungsten is
comparatively soft.
COUNT ON EACH FACE
● Sharpen your cutter wherever possible
from new to make sure that you have
an edge as it was designed to be. Some cutters need honing before use.
● Sharpen your cutter regularly; don’t wait
until the cutter is getting blunt because then
you will find that it is working too hard to do
the job. This is when you end up damaging
the cutter and throwing it away!
Rather than having to send cutters or saw blades
away to “Saw doctors” to be sharpened, losing
30%-40% of the face after it has been excessively ground away, maintain your own cutters.
● Use a Fine grit for Carbide Use a Coarser grit
for H.S.S. This is why the Trend Credit
Cardstone (the only double sided type on the
market) is ideal for sharpening cutters and
saw blades. As well as the narrow width
(0.8mm) enables you to get into sharpen
smaller and fluted cutters.
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● Saw Blades are very similar.
Sharpen on the flat face with
only three or four strokes over
each tooth.
● Use light pressure in forward and
backward strokes.
● Put the blade in a vice, chalk up
the first tooth and slowly work
your way around the blade.
● Regular maintenance with prevent
you having to send your blades
to a saw doctor resulting in
being charged for having 30%40% of the carbide face being
ground away.
● Spindle Knives again are a similar
to router cutters in that you must
sharpen from “the back side” and
never touch the profile edge unless
you wish to change the shape of
the cut.
● It is paramount that sharpening
spindle knives is done on a
Diamond Whetstone, which is precision flat.
● Use a fine grit.
● The most suitable stone available is
the Trend double sided (Fine
& Coarse) precision 7" x 2.5" bench
stone. It is finished off to
a flatness of + / - 0.0005", the flattest Diamond stone on the market.
This product was one of the ranges,
which contributed to the manufacturers in
England being awarded the Engineering
Excellence Award for 2006. Suppliers to the
likes of British Aerospace and Rolls Royce, it is
this type of pedigree which is needed when
sharpening precision tooling such as spindle
knives. This stone will again feature in our later
section on chisel and plane blade sharpening.
● These stones are also suitable for sharpening,
in exactly the same way, Horse & dog
clipper blades.
James T Barry
JAMES T. BARRY has been
involved in Diamond sharpening abrasives for twenty years
and is regarded by many as an
expert in his own field. Having
worked worldwide for DMT
(USA ten years) and gaining
further experience with Atoma
(Japanese) Titan (Swiss) products. In 1998 He decided that it
was time to try and put all his
experience into creating the
best quality engineered range
of Diamond Whetstones, most
importantly using the top quality engineering experiences
from UK manufacturers.
This was achieved in
January 2000 and Trend
Machinery & Cutting tools ltd.
requested the sole distribution
rights for UK and Ireland.
They duly did this and
dropped the DMT range from
their portfolio.
The product range has the
following unique properties:
1 The only Diamond range in
the World which is produced
in the UK.
2 The only range which uses
double sided continual diamond whetstones.
3 The only range which offers
a five-year guarantee.
4 The only bench stones which are available at a flatness of +/- 0.0005".
The product range has gone from strength to
strength, now available in the USA, Austria,
Scandinavia, France and Australia.
In March of 2006 the manufacturers have
been awarded The Engineering Excellence
Award for 2006.
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A Guide to Sharpening Chisels/
Plane Blades & Turning/
Carving Tools
W
ith all chisels and
plane blades one
of the most important factors is making sure
that the backs are totally flat
before trying to hone them to
a razor finish. The coarser
grits of Diamond whetstones
are ideal for this procedure. Once the back has
been flattened it is then a matter of seconds to
achieve the required edge.
● Sharpening with a Diamond Whetstone is
about 95% quicker than traditional methods.
● Do not apply too much pressure, “Let the
Diamond do the work.”
● A continual Diamond surface prevents snagging when sharpening smaller tools as can
occur when using Diamond stones with the
Matrix (holes) type surface.
● Diamond Whetstones sharpen both on the
forwards and backwards stroke.
● High quality Diamond Whetstones do not
dish or groove.
● “Back off” the chisel or plane blade and then
with a few light strokes apply a razor edge in
seconds
to
the
bevelled
edge.
Finish off by wiping off the burr that you
have created.
● Use with a lubricant to dispose of the
swarf. Highly recommended is the
Trend Lapping fluid, which prevents rust
and clogging.
● Honing guides can be used on quality
Whetstones without the fear of dishing
or grooving.
Turning and Carving tools come in many different shapes, which often can cause problems
when trying to sharpen on a flat surface.
Therefore you will probably find that a combination of a slip stone (The double sided Credit
Card) and a file which will enable you to penetrate those normally inaccessible areas.
● Gouges have either an internal or external
bevel edge.
● The majority have an external bevel edge,
place the bevel edge flush with the Diamond
surface then gently roll to sharpen the edge.
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● To remove the burr use a file, the Diamond
Penfile is ideal for this as well as being
the best for sharpening carbide tipped
ring tooling.
● Turning gouges should mainly be sharpened
using the coarse grit.
You more often than
not need a “coarse
sharp edge”.
● For the variation of
carving tools Needle
files can prove a
huge benefit in accessing difficult areas.
Needle files
● Needle files are available in a variety
of shapes. Triangular / Tapered Flat Half
round / Flat & Tapered Round / Tapered
The Trend Diamond files are of the highest
quality (as supplied to British Aerospace
and Rolls Royce) Sold individually or in a
set of four.
DOMESTIC GENERAL SHARPENING
Away from the workshop or site work, there is
still plenty of sharpening to be done in the
home, in the garden or maybe even on fishing or
hunting trip.
Diamond Whetstones are not just highly efficient on woodworking tooling but also Knives,
secateurs / pruners, shears, scissors, axes, craft
knives, serrated blades, hoof knives etc.
● Scissors / Shears
Align the slip stone flush with the bevel
edge then stroke softly along the blade.
Remove the burr
Pocket 5
that you have raised
Double sided
by one clean stroke
fine / coarse
flat to the other side
of the blade. Repeat
process to the other
blade. For domestic
scissors use the
Fine grit for garden
shears or other heavy-duty applications use
the coarse grit.
● Secateurs / Pruners
Similar to the sharpening of the scissors or
shears, secateurs have a bevel edge and a
flat edge. Align the
Diamond slip stone
to the bevel edge
and in a circular
motion slowly go
down the length of
the blade. Once
you have put the
edge on the bevel
side, turn it over and remove the burr you
have created keeping the slip stone flat to
the blade.
● Serrated knives / Hoof knives
For serrated knives
simply use a Diamond file to go into
each serration and
lightly sharpen the
bevel edge. Once you
have done this turn Diamond Penfile
the blade over and,
keeping the file flat to the other side, remove
the burr you have created with one simple
stroke. Hoof knives have always created a
problem with the hook at the end of the
blade. With the Penfile you can easily access
& sharpen this area.
● Knives: Domestic /
Hunting & Utility
With Diamond Steels
or the universal Penfile it is possible to
put a razor edge back
on knives in seconds
and then maintain it.
● Many people have problems maintaining
an edge to their kitchen knives as when they
are purchased from new. The old tradition-
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al method of using ordinary steel can be a
very “hit or miss” affair. The major problem
with conventional steels is that all you are
doing is re-aligning the edge, so eventually
you end up with a blade with very thick
shoulders to it that would probably need regrinding. Some people try and use any of
the vast array of “pull through” sharpening
gizmos. Again the major problem with
these is that the pair of wheels (or whatever
sharpening medium is used) leaves a very
rough, bumpy almost saw like quality to
the blade.
● The main advantage with using Diamond
products is that you are removing a small
amount of material from the blade on
each stroke, so therefore you only need
a few alternate light strokes to achieve
the edge.
● A flatter angle for a filleting edge. A
steeper angle for a boning edge. For the
majority of domestic knives use approximately a 20% angle.
● Use a shallow angle / alternate light strokes
down the length of the blade as in the
diagrams shown on the right.
● Stroke away
from the body
for safety.
● Sharpens stainless steel.
● To clean use a damp cloth to remove the
swarf or rub down with a drawing office
type rubber (putty rubber)
● These Diamond steels have been used by
some of the leading Chefs on the Television
(e.g. Harriot & Oliver).
● Alternate strokes / Shallow angle /
Little pressure.
James T Barry
“The main advantage
with using Diamond
products is that
you only need a few
alternate light strokes
to achieve the edge.”