I've always envied people who could sharpen tools to
perfection. I tried for quite some time on and off, but found it very
difficult, tedious and frustrating to do. I found all those simple
'swipe through' gadgets quite satisfactory for many years, but as I got more
involved with knife making, they no longer sufficed because I got hung up
with wanting all my knives to be shaving sharp! Therefore, I had no
alternative at the time but to force
myself to learn and do it properly.
All my initial efforts were based on ignorance,
believing that the more I practised the better I'll get. All I did was
to make matters worse because my equipment and techniques were wrong and I
kept on failing miserably! I began to shy away from sharpening
anything unless I could use a gadget of some sort. I kept trying
different things and discovering the odd bit of kit that worked for me,
until I can now say that at the time of writing this I'm nearly there in terms of producing shaving sharp edges
consistently, and nearly there with having the right gear and being
effective/efficient in utilising it. It's still a labourious and tedious
affair, that's for sure! Maybe I'll get to like it in time. I have one or two ideas I want to
try out to make my task a bit easier, but for now I'm pleased to have got
this far. At least now I partly enjoy the process and I find it very
absorbing. On the downside, the back of my left hand is nearly bereft
of hair as that's how I test if I got the blade sharp enough!
Maybe I'm overly fussy, but I'll not consider any
knife of mine finished and fit for purpose unless it's shaving sharp. To get
most blades to that state it takes me from between 1 or 2 hours - so
patience and perseverance is a must.
At time of writing, the tools I use are as shown in this picture:
1. Own made Grind type checker and setter
2. Coarse Diamond stone.
3. Medium Diamond stone
4. Fine Diamond stone
5. Japanese Combination
Waterstone - 600 / 1000
6. Ex - Oil Stone
2,3,4,and 5
only used with water.
1 and 6 used dry and/or with water as they're Carborundum stones..
I normally start the process with swiping the blade through my homemade
grind checker if I'm not sure of the grind. A few swipes through this
little gadget and I'm able to see exactly whether it's a hollow or convex
based grind.
The close up of this
little tool shows how I slotted two small stones side by side in a block of
wood. The slot is slightly wider at the top and the stones are not
fixed in, but held in place by stretched Bicycle rubber tubing along the
bottom half of the stones. The top of the stones extend about half way out
from the block. What happens is that when I swipe the blade between
the stones, the top part opens up more than the bottom part (which flex a
little also because of the rubber backing) and thus creates a natural V.
I also use this to take out a secondary bevel by running the blade through a
few times. I use it wet or dry depending on how much I need to score
or take off the existing bevel.
In effect, the proper sharpening process is not until the very end
as what needs to
be done first is to try and set the correct angle of the grind as
near as
possible to the desired final shape. I find that the three grades
of
Diamond stones are great for this, not just because they're so
effective, but
at the beginning at least, I hold the stone in my right hand and
move it
across the blade so I can see better what I'm doing. I'm also far
more
in control as I can change from a flat rub to a rocking motion at
will. It's at the finishing stages that I lay the stone flat
and move the blade over it. I go through all three Diamond stones
until I'm satisfied I can move on to the final sharpening phase.
For the final phase I use a 600/1000 grade Japanese Waterstone, which I
would have left soaking in water for some time before I needed it. It is now that I keep
the stone flat and run the blade over it, first on the coarse side (dark
brown), then on the fine side (light brown). It's not easy to explain
the process of working with a Waterstone, but it's very far removed from
working with Carborundum stones. The whole process is smoother and
best of all you're not left with any scratches on the blade. As if by
magic, the blade is sharpened and polished at the same time. The stone
is on the soft side and it's very easy to dig into it with the blade, but
it's very efficient and the results are outstanding.
Stone number 6 is an oil stone, or it was one once. I de-greased it
and now use it mainly
dry to check for raised/hollows as it marks the blade well but not
too deeply. I also use it frequently while
working with my leather knives as I find the slightly serrated edge such a
stone produces gives me more bite when cutting leather.
Now take a look at the damaged knife edge below and to what level
the blade was finished by the waterstone in the photo below it.. At this
stage the blade was not yet polished on the buffer, but by the waterstone
alone.
The knife in question was one of five prototypes that I rushed off
that ended up severely tested in the field in temperatures down to -40
degrees! As can be seen the knife got a bit of a battering! The knife had a small secondary bevel originally,
but was re-ground by hand to a flat V. As it turned out, it wasn't
such a good idea on such a deep and shallow set grind of 13mm because there
wasn't enough substance to back up the fine cutting edge.
This was an important lesson learned from actually having to make do with
the one knife under extreme conditions.
As a consequence, the second batch had a grind of 8mm making
for a steeper angle and were thus better able to cope with tougher tasks.
But, even so, one can't expect that the one small knife to be better than
having a two knife Puukko and Leuku combo. In my view, small knives
for small jobs and big knives for bigger jobs.
Frenchy
16th March 2007
www.customknivesandsticks.co.uk