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I explain how I remove the excess metal at the front, and top edges of a chisel
All bevel edged chisels
I have owned over the
years have required
the excess metal on
the front edges of a
chisel to be removed
to make them suitable
for fine dovetailing.
Without carrying out
this process you will
damage the side of a
‘tails’ of a dovetail
joint.
I have owned over the
years have required
the excess metal on
the front edges of a
chisel to be removed
to make them suitable
for fine dovetailing.
Without carrying out
this process you will
damage the side of a
‘tails’ of a dovetail
joint.
GriEgs01
But just as a reminder, the
jig can also be used to
convert a firmer chisel into
a bevel edged chisel.
jig can also be used to
convert a firmer chisel into
a bevel edged chisel.
GriEgs02
When a chisel is set up
in the jig, initially only
a small portion of the
chisel will be in
contact with the
grindstone.
In order for me to
illustrate this point I
have used a rule,
rather than a chisel.
The rule is touching
around the 45mm
mark.
I will refer to this point
on the stone as the
‘contact point’
in the jig, initially only
a small portion of the
chisel will be in
contact with the
grindstone.
In order for me to
illustrate this point I
have used a rule,
rather than a chisel.
The rule is touching
around the 45mm
mark.
I will refer to this point
on the stone as the
‘contact point’
GriEgs03
and we need to set up
the chisel in the jig, so
that the surface I am
pointing to with the
pencil is flat on the
grindstone.
the chisel in the jig, so
that the surface I am
pointing to with the
pencil is flat on the
grindstone.
GriEgs04
like this.
So what angle is this?
Well from my
experience, each size
and make of chisel has
a different angle of
bevel, so whatever that
angle is, I still rest the
bevel flat against the
grindstone.
So what angle is this?
Well from my
experience, each size
and make of chisel has
a different angle of
bevel, so whatever that
angle is, I still rest the
bevel flat against the
grindstone.
GriEgs05
How far past ‘contact point’ on the grindstone do I position the chisel?
Well that depends on the width of the chisel. The chisel in the image below is 19mm(3/4”) wide, so the end of the chisel was
around 10mm(3/8”) past the ‘contact point’ on the grindstone.
In practice I mark the 10mm line in marker pen on the bottom of the chisel. I have also added, for the sake of illustration purposes,
the ‘contact point’ in black pen on the grindstone.
For a 6mm wide chisel the front end of the chisel would project around 3mm.
For a 3mm wide chisel around 1mm.
GriEgs06
Well that depends on the width of the chisel. The chisel in the image below is 19mm(3/4”) wide, so the end of the chisel was
around 10mm(3/8”) past the ‘contact point’ on the grindstone.
In practice I mark the 10mm line in marker pen on the bottom of the chisel. I have also added, for the sake of illustration purposes,
the ‘contact point’ in black pen on the grindstone.
For a 6mm wide chisel the front end of the chisel would project around 3mm.
For a 3mm wide chisel around 1mm.
GriEgs06
Having set the relevant projection, the chisel is secured in the jig. Once you are completely happy that you have the correct set up in
the jig, grind away one of the edges. In practice you may have to increase or reduce the amount of projection fractionally.
In the case of Japanese chisels you will see from the above image that you need to be careful that you don’t grind away too much
metal from the flat surface, otherwise you will grind into the hollow section.
Having ground one edge successfully, leave the chisel in the jig, and using a diamond stone remove the razor blade sharp edge that
has been formed where the excess metal has been removed between the edge and the bottom of the chisel.
GriEgs7a
the jig, grind away one of the edges. In practice you may have to increase or reduce the amount of projection fractionally.
In the case of Japanese chisels you will see from the above image that you need to be careful that you don’t grind away too much
metal from the flat surface, otherwise you will grind into the hollow section.
Having ground one edge successfully, leave the chisel in the jig, and using a diamond stone remove the razor blade sharp edge that
has been formed where the excess metal has been removed between the edge and the bottom of the chisel.
GriEgs7a
Then before you
rotate the chisel in
the jig to grind the
opposite edge,
measure the
projection of the
chisel from the end
of the chisel to the
front end of the jig.
rotate the chisel in
the jig to grind the
opposite edge,
measure the
projection of the
chisel from the end
of the chisel to the
front end of the jig.
Then before you rotate the chisel in the jig
to grind the opposite edge, measure the
projection of the chisel from the end of the
chisel to the front end of the jig.
GriEgs07
to grind the opposite edge, measure the
projection of the chisel from the end of the
chisel to the front end of the jig.
GriEgs07
And that was in the region of 74.5mmm.
Then rotate the chisel so that it is resting
on the opposite bevel, check that it is still
projecting the same amount from the jig,
then grind the second bevel and remove the
sharp edge as before.
GriEgs08
Then rotate the chisel so that it is resting
on the opposite bevel, check that it is still
projecting the same amount from the jig,
then grind the second bevel and remove the
sharp edge as before.
GriEgs08
And that was in the
region of 74.5mm
for this chisel.
Then rotate the
chisel so that it is
resting on the
opposite bevel,
check that it is still
projecting the same
amount from the jig,
then grind the
second bevel and
remove the sharp
edge as before.
region of 74.5mm
for this chisel.
Then rotate the
chisel so that it is
resting on the
opposite bevel,
check that it is still
projecting the same
amount from the jig,
then grind the
second bevel and
remove the sharp
edge as before.
Now for a chisel that is around 19mm(3/4”)
wide the top surface where the grinding has
taken place is still flat and as such will only
require a small amount of work with a
diamond stone to round over the edges.
However the chisels that are between 3mm
and 9mm wide tend to have their bevelled
edges coming to a point like this and as such
is uncomfortable to work with unless
removed.
wide the top surface where the grinding has
taken place is still flat and as such will only
require a small amount of work with a
diamond stone to round over the edges.
However the chisels that are between 3mm
and 9mm wide tend to have their bevelled
edges coming to a point like this and as such
is uncomfortable to work with unless
removed.
Now for a chisel that is around 19mm
(3/4”) wide the top surface where the
grinding has taken place is still flat and as
such will only require a small amount of
work with a diamond stone to round over
the edges.
However the chisels that are between 3mm
and 9mm wide tend to have their bevelled
edges coming to a point like this and as
such is uncomfortable to work with unless
removed.
GriEgs09
(3/4”) wide the top surface where the
grinding has taken place is still flat and as
such will only require a small amount of
work with a diamond stone to round over
the edges.
However the chisels that are between 3mm
and 9mm wide tend to have their bevelled
edges coming to a point like this and as
such is uncomfortable to work with unless
removed.
GriEgs09
So I set up the
chisel in the jig
like this.
chisel in the jig
like this.
So I set up the chisel in the jig like this.
GriEgs09a
GriEgs09a
so that part of the top edge
is removed. The adjoining
edges will then have to be
rounded over using the
diamond stone, making the
chisel comfortable to work
with.
is removed. The adjoining
edges will then have to be
rounded over using the
diamond stone, making the
chisel comfortable to work
with.
so that part of the top edge is removed.
The adjoining edges will then have to be
rounded over using the diamond stone,
making the chisel comfortable to work
with.
GriEgs10
The adjoining edges will then have to be
rounded over using the diamond stone,
making the chisel comfortable to work
with.
GriEgs10
And I grind the chisel at an angle of
23degrees because I will be using the
chisel like a paring chisel. In other words
without using a hammer.
Originally before I made this jig, all of the
grinding process were carried out
freehand, something that for sure would
not comply with any health and safety
manual.
23degrees because I will be using the
chisel like a paring chisel. In other words
without using a hammer.
Originally before I made this jig, all of the
grinding process were carried out
freehand, something that for sure would
not comply with any health and safety
manual.
And I grind the chisel at an angle of
23degrees because I will be using the
chisel like a paring chisel. In other words
without using a hammer.
Originally before I made this jig, all of the
grinding process were carried out
freehand, something that for sure would
not comply with any health and safety
manual.
GriEgs11
23degrees because I will be using the
chisel like a paring chisel. In other words
without using a hammer.
Originally before I made this jig, all of the
grinding process were carried out
freehand, something that for sure would
not comply with any health and safety
manual.
GriEgs11
Using this jig and the
methods described, I
have reground a
3mm chisel to
around 1mm
methods described, I
have reground a
3mm chisel to
around 1mm
Using this jig I have reground a 3mm chisel
to around 1mm
GriEgs12
to around 1mm
GriEgs12
and another at 1.5mm
GriEgs13
GriEgs13
and another in the
region of 1.5mm
region of 1.5mm
and reduced a 9(3/8")mm wide firmer chisel into
a smaller ‘skew chisel’ for getting into the
corners of the dovetail sockets.
a smaller ‘skew chisel’ for getting into the
corners of the dovetail sockets.
and reduced a 9mm wide firmer chisel into
a smaller ‘skew chisel’ for getting into the
corners of the dovetail sockets.
GriEgs14
a smaller ‘skew chisel’ for getting into the
corners of the dovetail sockets.
GriEgs14
In the next chapter I will deal with flattening
the bottom of a chisel.
the bottom of a chisel.
If you have benefited from this web page and would like to contribute to good causes listed below are charities of my
choice.
The Alzheimers Association. www.justgiving.com/hand-cut-dovetails
Water aid www.justgiving.com/hand-cut-dovetails1
Dreams come true www.justgiving.com/hand-cut-dovetails2
Help for heroes www.justgiving.com/hand-cut-dovetails3
The Wounded Warrior Project www.firstgiving.com/fundraiser/hand-cut-dovetails/alan
choice.
The Alzheimers Association. www.justgiving.com/hand-cut-dovetails
Water aid www.justgiving.com/hand-cut-dovetails1
Dreams come true www.justgiving.com/hand-cut-dovetails2
Help for heroes www.justgiving.com/hand-cut-dovetails3
The Wounded Warrior Project www.firstgiving.com/fundraiser/hand-cut-dovetails/alan