pathfinder

®
THE WoodRat
PATHFINDER™
The Pathfinder™ is a system of plates that works as
an accessory to the WoodRat WR5, the LittleRat
LR1, the current WR900 and the WR600. It’s made
up of the Pathfinder Parts, the MitreBox MB3 and
one of a series of Templates. What it will produce
will depend on the type of Template used.
1
Contents
Introduction
Before you begin
parts not included in the Pathfinder
The Pathfinder™
MitreBox MB3
Pathfinder Parts
The Templates
Tenons
Set up for Tenons
Making the tenon
Making the mortise
Dovetails
Set-up for Dovetails
Symmetrical Dovetails:
the Tail sockets
Test Pins
Run of Pins
Asymmetrical Dovetails
Grooving
Half Blind or Lapped Dovetails
Set-up
Making classic drawers
Tail sockets
Test pins
Run of Pins
The Blank Template
2
Introduction to the Pathfinder™
A few years ago certain companies began producing Mortise and Tenon jigs to simplify the process
of making mortise and tenon joints and at the same
time to solve the problem inherent in routing with
a round bit, which is that it makes round ended
mortises – the proverbial square peg in the round
hole.
This niggled at us too, but having the WoodRat as
a starting point, the direction it took us surprised
us by producing not only a foolproof way of cracking out tenons, but it also led on to a whole variety
of joints – tenons, through dovetails and half-blind
dovetails and all sorts of shapes and so on, each
ve Moreover it was all based on familiar WoodRat
technology.
The one thing that it did not produce was an easy
way of making mortises. But then mortises are traditionally made in a very separate way from tenons,
and our solution for them, the MR4 Mortise Rail, has
also led us to a lot of other ways of making many
interesting things.
I hope you get great pleasure from the Pathfinder as
well as finding it useful. It is still in the experimental
stage and the invitation is there for you to join us
in discovering innovative ways to use it. Keep in
touch.
3
PARTS LIST
PARTS FOR THE PATHFINDER™ Pf1
The Pathfinder™ uses the WoodRat MitreBox MB3 to hold the workpieces plus several
new components (Pathfinder Parts) that enable it to track the pathways in the
Templates. Templates come in a variety of patterns depending on the joint or
component to be made.
The WR600, WR5 and the WR900
3142 Guiderail Right
:
1. Pathfinder Parts
Half plate
make a suitable platform for the Pathfinder. Use your
Alu GuideRails and Router Plate RP3 (with new hole
configuration) and raising plate if necesary. Older
GuideRails need an extra counterbored M4 hole, and
you will need to drill and tap older Router Plates or buy
a new RP3 Router Plate. The new Ali Fences are ideal for
firming up the MitreBox.
6541 Starknob
Halfplate
Drop-Pin Plate
Drop pin
Bracket
M6 Locking screws x4
M8 20 x2
Drop Pin
M6 Locking screw x2
2. MiterBox MB3
Drop-Pin Plate
6461 Routerplate
3141 Guiderail Left
3316 Raising Plate
Use your Raising
Plates if needed for
extra depth for
tenons
Right-hand
M8 Self-tapping inserts
Left hand Cheek
Right hand Cheek
M4 16 x 4
M4 nuts x 4
Rod Clamp components
5424 Locking Lever
5421 Lobed Washer
M10 nuts x 4
M10 washers x 5
300mm threaded Rod x 2
M8 self tapping inserts x 2
M8 nut
5512 Rubber washer x 2
Rod Lock
5424 Locking Lever
M8 nut
M8 50
Spreader Rod
6mm Hex key
4262
Aluminium
Fence
6421 Lobed Washer
Left-hand Cheek
Attaches to the Left
hand Cheek to secure
the MitreBox.
M6 Locking key x 2
5616 M4 16
Aluminum Bracket
5684 4M Nut
3. Pathfinder
Templates
There are a growing selection
of Templates for a wide variety
of tasks. They can be made to
order.
Tenon Template
Through DovetailsTemplate
Half-blind Dovetail Template
Although we will try to advertise any item changes in good time, in the interest of continuous improvement in the quality and value of our products,
WoodRat reserve the right to change components in colour, function and material without prior warning.
4
Before you begin
Some parts are not part of the Pathfinder, as they are
now a standard part of the WoodRat kit. They can be bought
separately from your WoodRat dealer if you need them.
1. The Aluminium Fences
We have recently introduced new Aluminium Fences to replace
the earlier moulded nylon ones. Firm and square enough for
ordinary purposes, they are well worth having for Pathfinder
work as they allow you firmly to attach the Left hand Cheek
to the Sliding Bar to form the MitreBox MB3.
5616 M4 16
5684 4M Nut
The aluminium fence has two tee-slots
that will hold the left-hand cheek firm
and square to the sliding bar.
The Fence has two tee slots in it so that the Left hand Cheek
can be bolted to it with four M4 16 screws to hold it firm and
exactly square. A third tee-slot behind the finger grip takes
the Big Cursor. This is not generally of use with the templates
which have their own way of registering where the cuts are
to come.
The ali fences come with wooden faces that allow you to add
sandpaper to stop the wood slipping. Do not sandpaper the
aluminium Fence direct.
But now take off the Ali Fence. Take off the Plywood Face
and store it, before you put the Left Cheek into the tee-slots
of the Sliding Bar.
The M4 16 screws go into cheek. The nuts go on loosely and
the Cheek is slid into the tee-slot of the Sliding Bar The Fence
is slid upwards onto the nuts before being screwed to the Bar,
and the M4 screws tightened.
2. Ali GuideRails:
You will need your WoodRat or LittleRat GuideRails. Note
that there is an extra M4 threaded hole in the HalfPlate. If your
GuideRails do not have corresponding holes, you will need
to drill them 4mm counterbored to 8mm to house the head
of the M4 10 screw. These extra screws stop the routerplate
from twisting the rails out of true, and hold everything firm on
the Half Plate.
3. The New RP3 RouterPlate has 6 x 6mm tapped holes that
take the locking keys for the Drop-pin plate. If you have an old
routerplate and you are not confident at drilling and tapping,
it might be best to buy a new RP3.
The guiderails have an extra pair of counterbored
4mm holes to take an
M410 to attach it to the
half-plate
Otherwise the RP3 is similar to the RP2 routerplate except
that is has two extra tapped M8 holes for attaching fences
of different types to the underside of the Plate. This allows
you to use the Router for freehand work without taking the
router off the Plate. You have the advantage of a larger base
for the router, plus the ability to make a fence that suits the
job in hand: 8mm deep for running against an 8mm straight
edge laid across a sheet of material or, for example, deeper
for moulding the edge of a table, for example.
The router plate has
three pairs of M6 holes
to take the Drop-pin
plate
5
Setting up the Pathfinder™
The Pathfinder™ Pf1 comes in three parts. They can be
bought separately, or bundled together. If you have an
MB3 MitreBox you will need only the Pathfinder Parts and
a Template to begin wo.
Most of the actions and techniques such as the tracking, holding wood in the CamLocks, using the raising plates, plunging
and depthing the router, will be familiar to anyone who knows
the WoodRat, but if you are new to it, you will find it helpful to
read the Manual that comes with your basic machine, and put
in some practice.
The workings of the Pathfinder itself are mostly self-evident. Tenons are a breeze and Through Dovetails are not too difficult, but
the Half-Blinds are so quick in operation that it is well worth the
initial mental effort. It’s even worth following the instructions.
Drop Pin
M6 Locking Key
M6 Locking Key
Drop Pin Plate
1. The Pathfinder™ Parts
The first part of the Pathfinder is what we call the ‘Pathfinder Parts’.
These need to work with the MB3 MitreBox to complete the Pf1
Pathfinder™.
1.1. The Halfplate
The BasePlate of the WoodRat is replaced for Pathfinder work
by the HalfPlate. The front edge of the Halfplate has a groove
that takes the tongue cut into edge of all the Templates which
interlock with it and can slide east/west with no north/south
movement. Use the M8 25 screws that come as standard with
the WoodRat kit.
Raising Plates
Loosen the HalfPlate and add Raising Plates under it as necessary to give more depth of cut. The Raising Plate (or plates) come
as standard with the WoodRat kit, to allow a greater depth of
cut when needed for tenons. It uses the M8 25 or M8 50 screws
which come standard with the WoodRat kit. Plus the M4 10
screws to hold the GuideRail to the Halfplate.
1.2 Drop-pin Plate
The new RP3 RouterPlate is largely the same as the older Plate
but is modified to take the Drop Pin Plate. This fits into its tee slot
and is held either side by M6 10 Locking Keys. Its position can
be adjusted north/south in the RouterPlate, and it can be locked
down. It determines the distance between the Pin as it wanders
around the template and the Bit as it cuts the workpiece.
It governs the distance between the Bit and Pin.
The Drop Pin
The Drop Pin has a sprung pin that can be raised and kept up,
or dropped down to engage with the grooves, islands, wedges
and pathways in the Template. So, as the Template and with it
the Workpiece is tracked west/east, the Pin, and with it the Bit,
can go north/south.
So in effect, the pin finds its way around any useful kind of Pathway cut in the template allowing the bit to travel a similar kind of
pathway in the workpiece; hence the name Pathfinder™.
6
Make sure that you have the
4mm counterbored hole here.
1.3. The Bracket
This attaches to the Left Hand Cheek of the MitreBox MB3. The Cheek
must be fitted with two M8 brass inserts which take the two M8 25’s.
They go through the two vertical slots, allowing the Bracket, and the
Template with it, to be raised up under the Guiderails when the Raising Plate is in use.
The Bracket also has two open slots which take the M6 Locking Keys
screwed into the Template. The keys, when loose, can slide in the
slots and can be positioned and tightened up, so that the Template,
sliding in the groove in the HalfPlate may be tracked east/west under
the RouterPlate,
This east/west adjustment of Template on the Bracket governs the
way the joints are laid onto the workpiece.
M8 Self-tapping inserts
M8 nut
M8 50
6mm Hex key
1.4. The Brass Inserts
There are two brass inserts that need to be wound into the two holes
at the top of the left Cheek. they can be driven in with a large screwdriver, but it is simpler to use a long M8 socket head cap screw. If
you just use the screw, put the insert on it, and wind it in with the hex
key, you might find that the insert jams on the screw and unscrews
when you wind the screw out again. A nut on the screw, then the insert, before winding it in will prevent this happening. Make sure that
it winds in straight.
Recently we have been placing the inserts for you.
2. The MitreBox MB3
This is the second part of the Pathfinder™
There are differences between the setups needed for the different
Templates, but this is the basic system:
2.1. The Left Cheek
of the MB3 attaches to the Ali Fence. It is placed first with its ‘toes’ in
the big tee-slot of the Sliding Bar. The four M4 16 screws are put into
the four counter-bored holes in the Cheek with the M4 nuts placed
loosely: the Fence is slid upward taking the nuts into the two tee-slots
and the Fence is screwed to the Sliding Bar with the M8 countersunk
screws in the usual way. Before the four M4 16’s are tightened fully,
pull the Fence forward and push the Cheek gently but firmly against
the Machine Face to take out any slack in the Bar.
For most work with the Pathfinder you only need the Left Cheek. When
you do need the Right Cheek, you’ll need the RodLock to hold it all
firmly, as a Box.
Set up the parts of the Pathfinder as the diagram. For the WoodRat,
use the right-hand CamLock. The LR1 and WR600 have only one gate,
but the process is exactly the same.
Some people buy an extra fence so that it can be kept permanently
with the left cheek.
2.2. The Right Cheek
The right-hand cheek is the thinner one. You’ll not
need it for the tenons or for through dovetails: only
later, for half-blind dovetails, and for mitred work
generally.
The cheeks are made of HDF which
is brittle, but can be drilled, worked
and added to.
The WoodRat manual gives a lot of
hints on how to use the MitreBox
for many other uses than simply
working at 45° angles
7
2.3. The Rod Lock
The threaded rods and how they are used is covered in a later
section on Half-blind Dovetails.
3. The Templates
The third essential part of the Pathfinder™ is the Template. These plates have a shaped long edge that interlocks with the Half-plate. They each have a way
of being screwed to slots in the Bracket, using
M6 Locking Keys from below.
3.1. The Tenon Template
works with straight bits: 8mm 10mm and Half
inch. It will make Twin and Single and Double
Twin tenons in a range of lengths. The tenons
can be made round or square ended. It
will also make dowels. This technique
complements mortises made in the MR4
Mortice Rail.
Rod Lock
3.2. Through Dovetail Plates
Each plate makes classic through dovetails of fixed pitch but for a range of sizes
of dovetail bit.
5424 Locking Lever
Spreader Rod
6421 Lobed Washer
3.3. The Half-Blind Dovetail Template
is the fastest way to joint drawers. Each Template has two different pitches for the same size
of WoodRat dovetail bit. This Template and the
correct bit have to be used together.
3.4. There is also a Blank Template
You can cut out any shape in 3mm sheet acrylic and make
from it any wooden shape you wish. Any kind of shape that
can be devised in the template can cut a similar shape in
the wood.
The pathway might make stars, animal shapes for a Noah’s
Ark, or a line of multiple Santa Clauses. More practically,
circles or squares will make inter-locking lids and boxes. You
will need to experiment with different sized bits and different
thicknesses of wall for the drop-pin to run against.
8
Working with the Pathfinder
Preparation
However well the WoodRat parts are finished, your Pathfinder parts, plates and sliding bar, will need to be thoroughly waxed and polished before work can begin. The
whole mechanism must run like silk.
When the Template is added it needs to be locked in so
that there is the minimum of movement when the pin is
dropped, for instance, in the centre hole in the tenon
template. You will need to check that the router plate
runs smoothly fore and back and that there is no sideways slap between plate and guiderails.
It might be necessary to take everything apart to ensure
that all sliding parts are as slick as can be.
Holding the work
Locking a rail in the Camlock is the same as for general WoodRat work, you need to pull with your fingers and push with
your thumb as you clamp in the work, to take out any slack in
the sliding bar, and make sure it’s firmly seated. Bring up the
Camlock, and lock in a scrap rail, making sure that the Bar
tracks nicely west/east....
and that the Router runs smoothly north/south: if necessary,
wax all rubbing surfaces. Take out any lateral movement between GuideRails and RouterPlate.
d
Simple strips of sandpaper
are quite adequate to hold
the wood vertical, horizontal
and at angles.
Sandpaper your faces:
to give some friction to the inner faces of the Cheeks, we recommend that you sandpaper the faces. Use impact adhesive,
pasted on both surfaces and allowed to dry before bonding
the two surfaces together: this makes for very durable non-slip
surfaces to hold the work. Alternatively use a rubber cement
(Copydex) that does not last for ever, but which can be peeled
off and replaced more easily.
Use around a 120 grit and trim round the Cheeks with a sharp
knife.
Dust Extraction
Ensure that you have good strong dust extraction, particularly
for the harmful fine dust.
Note: LR1 LittleRat users can use the new RP3 RouterPlate for
all normal LittleRat work except variably spaced half-blind dovetails.
Either revert to your LittleRat router plate or invest in a HalfBlind
Dovetail Template and use the Pathfinder™.
The Bracket
The Alu bracket is set by screwing two M8 20 screws into
the brass inserts. Do not tighten the screws you have set the
Template, and raised it up under the guiderails. The slots allow
you to raise the Template when Raising Plates are in use.
Check your router for run out. Make a test cut with a straight
bit in some hardwood scrap to check that a socket made
with a 10mm bit is indeed cutting 10 mm wide. If it is cutting
large, check that there is no slack between the guiderails and
routerplate.
If there is still serious run-out and you are using a quick release
chuck, re-insert your original collet and try again. If there is still
run-out, you have a problem with the router. if not, you have a
problem with the quick release chuck. In which case undo the
chuck and turn it a quarter turn and retighten, and test again. This
may improve the seating. If you cannot improve it, let us know.
9
A collection of tenons made during the experimental
stages of developing the Pathfinder.
The collection comprises tenons double tenons and dowels and stars made
with a star shape placed in the blank template
10
Using the Tenon Template
Aluminium
guiderails allow the
router to cut the
work on the axis
north/south
The Drop-pin in the
Drop-pin plate follows
around the ‘islands’ in
the Template, as the
Bit cuts the
workpiece under
the plate
The half-plate
holds the
Template as it
slides East/West
The Tenon template allows the
work to move east/west depending
on the drop-pin controling the
Bracket is raised so as
to lift the Template up
under the half-plate
position of the router. With this
Left Cheek of the MB3
mitreBox only is used
for makingTenons
Template it makes round ended
tenons – double and twin, and also
dowels.
Pathfinder Tenons – either single or double – are ver y straight for ward. The Template
forms not only round ended tenons of various useful sizes, but also dowels at the extreme left, and a long tenon that can be used for square ended tenons with haunches at
the extreme right of the plate.
Introducing the Tenon Template.
Polish all sliding surfaces so that everything slides easily when
it should, or locks down firmly when it needs to be firm.
Look at the rail end, and check it against the islands to decide
whether you need twin or single, or single or double tenons.
Or double twins.
Use the left-hand Cheek only. Place one 25mm/1” or two
12mm 1/2” Raising Plates under the HalfPlate to give you up
to 50mm/2” depth of cut.
Decide which bit you are going to use for your mortises, and
therefore the tenon size. The Template will make your tenons
either 8mm, 10mm or half inch, so your mortises will be either
8, 10 or half inch.
The Tenon Template has four lines of Islands – in two pairs of
two, each pair starts with circles and ends with long islands.
The top line of each pair is for single tenons; twins are made
using both lines.
As the Template is designed to make the tenon fit the mortise, you can make the tenons first. This has advantages over
making the mortises first, as we shall see.
Decide how long you need your tenon by matching the rail
end with an Island. At it’s simplest a single tenon will go in
the centre of the rail, but you can place it where needed. A
The tenon Template is designed to make tenons that fit mortises cut by an 8mm, 10mm or a half inch (12.7mm) bit.
11
twin tenon will have the socket between the tenons
placed central. To get the length of tenon, place your
work-piece against the islands to check which to use,
but note that the actual size of the tenon is 2mm or
so inside the island. Put a pencil mark on the Island
you are using so you can find it when it’s under the
plate.
With the upper pair of lines, use an 8mm
straight bit to make a 10mm tenon,
or a 10mm bit, to make an 8mm tenon.
With the lower pair of lines, use a 10mm
bit to cut a 1/2” (12.7mm) tenon,
or a 1/2” (12.7mm) bit to cut a 10mm tenon.
Select a bit to make the tenon you want and place
it in the collet.
Screw the Template to the Bracket loosely, and track
it under the Router Plate, threading the Template over
the supporting groove in the HalfPlate and under the
GuideRails. Lift the Template and Bracket gently up
under the GuideRails and tighten the M8 20 screws
on the Bracket. It should track west/east freely, so
make sure that it does.
The Drop-pin Plate
The Drop Pin screws into the Drop Pin Plate.
Place the DropPin Plate in the RouterPlate: screw in
a 6mm Locking Key loosely either side. See how the
plate will slide north/south when loose, and lock down
when the screws are tightened. By placing the screws
in one of the three pairs of holes, the pin can cover a
distance fore and back across the Template.
Lift the Pin, making sure that it moves freely over the
template. Note that the cutter is free to cut at random
into any work-piece placed in the CamLock when the
Pin is raised.
So raise the Bit. Get into the habit of raising the bit after each
run of cuts.
Drop the Pin and see how its travel is limited by the Islands of
the Template. Track the Crank Handle as you move the router
forward and back and see practice running around the Islands
in the Template.
Cross hairs find the
centre of the rail end
Marking the rail end
Mark up the end of the rail with two centre lines, the east/
west (x-axis) and the north/south (y-axis) line... and cam it
in place.
Note that there‘s no need to find the exact centre, as you can
make two lines, one from each face, rather than fuss about
finding the centre. Set your cutting gauge to roughly a half
and make two lines one from each face. One blade of the Bit
will later line up with one, and the other blade with the other
cut line, and the Bit will be exactly centered. If you have sharp
eyes or alternatively good 3 diopter specs, this method will be
extremely accurate.
The Bit finds the
middle of the rail,
while the Pin finds
the centre of the
Island
north/south
Note that the centre of the tenon might not need to be central
to the rail. It will depend on your design.
Two lines give the
centre line when
using a bit with
two blades
Locating the Template
Place the two M6 Locking Keys, in the correct holes for the
required Island. Note that the locking key holes are found two
places away to the left of the island you are using (the one you
marked up earlier).
Slide the Template so that the Locking Keys engage in the open
Bracket slots. Tighten them temporarily, and track the Bracket
and Template under the GuideRails and Router Plate.
Your marked-up Island will appear under the DropPin as the
crossed lines on the Rail end appear under the bit, but not
yet lined up. Now locate the Drop Pin in the hole in the Tenon
Island (the exact center of the Island).
12
east/west line
When the Pin is
in the centre of
the Island you
can line up both
axes on the cross
hairs.
The Channel
GuideRails
The half-plate
which is screwed
to the Channel
engages with the
Template, which
moves with the
workpiece.
Router Plate with Drop-Pin Plate with
Pin engaging in the Template. Lift the
Pin and the router is free
The Tenon Template
The Template slides east/west in the groove in the Half-Plate. The Drop Pin in its plate controls the action
north/south of the router. In effect you run round the template Islands with the Drop Pin which describes
the shape of the island on the tail end.
Slacken the Template’s M6 Locking Keys, and track the rail,
to centre the blades of the bit (set north/south) to align with
the y-axis lines. Tighten the screws. This positions the tenon
east/west on the rail end.
2. Locating the DropPin Plate
Loosen the DropPin Plate on the RouterPlate and move the
Bit so that the blades line up with the horizontal lines on the
rail end, then tighten the thumbscrews. You’re now aligned
north/south (on the x-axis).
The pin is still in the hole, so raise the pin.
This frees the router bit, so un-plunge the router at the same
time.
The Pin goes into the hole in the
Island, the Template’s Locking
Keys are slackened. The Bit lines
up on the centre line of the rail
end, and the Keys tightened.
Make it a habit: raise the router and the pin every time you
finish a joint. Then you can’t harm anything.
The Z-axis
Make sure you have enough depth of cut. Slide in a raising
plate as necessary.
Your rail will be marked out with the size between the stiles
and cut with adequate length of tenon at either end. So when
you place the rail beneath the plate you will be able to drop
the bit to the inside line of the door or frame. No zeroing the
bit this time.
13
If you work from an exact centre line, both your tenons will be
of equal length. They may be too long but you can cut them
down later. If too short, you will need longer rails.
Cutting the Tenon
Drop the bit and with the pin up and the bit down, you’re set
to go. You can now cut anywhere, so be careful.
Cut clockwise all around the rail to clean the shoulder of the
tenon. This without the pin hitting the Island. It is just to skim
the outside of the rail to make a clean shoulder all round.
Now drop the Pin and continue to cut the tenon clockwise. The
Pin wheel will now hit and run around the Island and describe
the outline of the tenon on the rail end at the same time. Go
gently and take your time.
With a little practice, you’ll find the best track to take, and
will develop your own techniques for maximum speed and a
perfect finish.
Go for finish first and speed later.
Nothing much can go wrong. If you find that the cutter is
cutting into the tenon, check that your locking pins are reasonably tight: the plate or the template can come loose, but
shouldn’t.
Be sure you are aware when the Bit is up and harmless, and
when down and meaning business, and when the Pin is up
and the bit not controlled by the template and when down and
only cutting where you need it.
Now the Pin Plate’s Locking Keys
are slackened. The Pin stays in
the hole, but the Bit is brought
forward to line up with the horizontal line.
Repeat for the tenon on the other end by cart-wheeling the
rail (the face side kept always against the machine face)... and
then the next, and so on.
Twin Tenons
Twins are made by running around the two twin islands together on the one rail. The centering method is a little bit
different:
Slacken the DropPin Plate Locking Screws. The y-axis alignment is done with the pin in the center hole as before.
But the centreline of the joint north/south is given by placing
the pin central between the Islands, and aligning the blades
of the bit on the y-axis lines.
The bit cuts round the tenon as
the Pin rolls around the island.
14
1. the rail is marked up
with “cross-hairs” and
tracked under the plate,
and the bit is centred
on them.
The halfplate is
shown partly
translucent
3. With the template loose, the pin is
moved up to the centre hole of the
island, and the template moved so
that the pin will fall in to it.
Tighten the locking keys
2. the drop pin is loosened, and taken to
between the islands and
the keys tightened.
4. Now drop pin and cutter, and cut
the twin tenons in the same way as
single tenons.
Layout for twin tenons using the bottom pair of lines of islands,
and the sequence for centering the tenons on the rail.
Double Twins
You can make double twin tenons if you don’t mind one pair
of twins being a little longer than the other. This can be useful
for placing a lock in the center rail.
Dowels
Dowels are very short round ended tenons, so they are made
in the same way as tenons, either single or twin. Note that they
have the advantage that one end of the dowel is integral and
need not be glued. The tenon is in the rail and stile is drilled
to fit it, making a stronger joint.
Note that the dowel can be made in anything... squares or
hexagonal pieces or twigs with bark on.
Note also that the bit does not have to be straight. You can put
nice finials on things with a cove or fancy cutter of any kind.
Gluing up
Tip. If you make too good a job of fitting the mortises to the
tenons, you could find that when you glue up and cramp the
pieces together, air, trapped in the joint, compresses and
shoots the joint apart again like an air gun when the clamping
pressure is released.
After making the tenon and before taking it out of the Camclamp, raise the Drop pin and just touch the tenon with the bit,
to make an airway. This is quicker than doing it with a chisel.
15
Haunched Tenons for Cupboard Doors
When making cupboard doors you can simply use the largest
tenon island, and run the cuts off both edges of the rail without
rounding either. Mark out the centre lines of your rail as described
earlier. Make the two cuts, trimming the shoulders, going clockwise
with the Pin down. Then raise the Bit by a gauged amount to make
the haunch. This means unlocking and raising the router itself
and lowering the Bit onto the gauging piece and locking it
again. Do not reset the depthing foot, just lift the router.
Raise the Pin and cut across to make the haunch on one end.
Cartwheel the Rail and tenon the other end. Make sure you haunch
the correct end of the tenon.
Bit up
Pin up
safe
position
Bit up
Pin down:
dry run as
the pin
follows the
template
Bit down
Pin down
safe cutting
as pin follows
template
Bit down
Pin up
Watch out!
Pin not in
control
Marking out for making a box
This is a time-honoured method for keeping the parts of a
project in their proper places and being able to tell which part
is which when they are disassembled on the bench.
Place the pieces together in the position that they will occupy
in the project: the two drawer sides facing away from you, for
example, and the ends across them, as you might find them in
a chest of drawers.
Put them together and draw an arrow across the top edges.
The arrows point away from you.
You will then be able to see at a glance which is the top edge
and which the left side and which the right, and which is the
inside and which the outside of the box.
Later you will then be able to see which Side goes with which
End to make a corner. Understanding this, you will never need
to get lost again.
The two sides,
collected together
and marked with
arrows pointing
the four pieces
orientated as they
are in the project
with the broken
arrows still pointing
away from you
If you have two or more drawers, you can draw a second or
third line under the arrow, or on the right hand edge of the arrow head. It’s simple but effective.
Making a box with continuous grain
Take a thick plank and re-saw it.
The trick is to turn the plank inside out so that the continuous
inside marking is on the outside. Mark up the parts as shown,
taking note of which is Side (the long pieces)) and which is
End (the shorter pieces). When rightly orientated, the arrows
will point away as shown earlier.
Mark up the boards with mitres the arrows give you the inside
and the upside of each piece the four pieces orientated as
they are in the project with the broken arrows still pointing
away from you: the two sides, collected together and marked
with arrows pointing away from you.
16
the arrows give
you the inside and
the upside of each
piece
Dovetailing using the TD Templates
For all those who have been perplexed by the workings of the WoodRat’s normal dovetailing method, this is an idiot-proof Dovetail Jig that never-the-less uses the WoodRat range
of fine 1in7 bits and produces perfect results. It’s dovetailing for the rest of us.
Set up for Dovetails
Start with the dovetail sockets:
To test the Template, you could make a simple box. You will
need a pair of boards for the box sides and a pair for the ends.
Make all the boards the same width, but the shorter pair will
be the ends and the longer pair will be the sides.
You need only the left-hand Cheek, the Bracket, one CamLock, and one of the Through Dovetail Templates for through
dovetails.
As always, through dovetails are made with the angled (dovetail) bit going straight through the work, with the straight bit
cutting at angles to make the pins.
Mark them up with triangle marks as shown (on page 14) so
that you don’t get lost and end up with a Z instead of a ring
of dovetails.
In other words, the angled bit goes straight and the straight
bit goes angled.
The bit
Choose a dovetail bit for the sides that is your next size larger
than the thic ness of the end or pin pieces.
So between the square Islands are for the tail sockets, with
the Pin running straight in the alleys between the Islands....
Note that you can match the bit size closely to the wood
thickness, if you have a good selection of WoodRat dovetail
bits.
whereas the Pins are made with the wheel running down the
sides of the angled wedges with the straight bit in charge.
17
You can also plane your wood down if it is too thick for the bit
that you want to use.
Tails first
You cut all the tails first because you can adjust the pin size to
fit later if you need to. There’s not much you can do to a row of
tail sockets.
Select a Dovetail Template. Screw in the two M6 thumbscrews.
Tighten gently and locate it exactly later (see below).
What size is the wood?
The width of the wood:
With any kind of jig you need to size the work to fit the jig’s fixed
pitch. This is the downside of having the speed and easy working
of this particular template. The Pathfinder™ Through Dovetail
TD Template has a fixed pitch, but you can use different sizes
of dovetail bit, and have therefore a lot of alternatives of wood
thickness at that same pitch.
The Bit is place on the central pin. The
Two Locking Keys of the Template are
loosed and the Template freed so that
the Drop Pin can go between the Islands.
The keys are tightened. That locates the
Template.
As the sockets get larger, in thicker wood, so the pitch gets
tighter, to a point where it looks camped and needs a wider
pitch. Then use a larger TD Template.
Making a symmetrical layout
Use the Template to show you where your joints are going to
come on the board end. It’ll show you how many pins you will
have, and whether you should narrow the boards to avoid oversized end pins.
Find the center line of the board end. When the board is symmetrical the line will be in the middle of an island or exactly
between two, depending on wheth er you have an odd or an
even number of pins.
Positioning the Tails
Place one piece for tails in the CamLock. Make sure that the
inside is facing you.
The Drop Pin goes between the Islands
to make the tail sockets.
1. Zero the cutter: raise the bit and then zero it onto the top
of the board.
Place the Bit so that it is positioned over the
middle of the board.
Depth the depthing fo t against the piece for pins
The Dovetail template is held by the Bracket and slides
2. Loosen the Drop-pin plate (you might have to relocate the under the Guide Rails. The Drop Pin traces the Tail sockLocking Keys to a different pair of holes), and bring the drop-pin ets by going through between the Islands using a Doveforward to about the middle of the line of square islands.
tail Bit and then traces the pins by going down the slope
of the wedges on either side.
3. Tighten the DropPin Locking Keys.
Track the board so that the centre line is precisely under the bit.
Loosen the keys on the Template.
Even Sockets Drop the Pin and slide the plate so that the pin
drops onto the middle of the middle Island, or in the alley between the two middle Islands. That should now put the run of
pins/sockets central to the board.
Now lift the Pin, so you can track the dovetail bit to the left-hand
edge of the board. Then run to the other end of the board and
check that the board is indeed central and the same both ends
with not too big a pin at either end.
Odd Sockets Drop the Pin and slide the plate so that it goes
between the islands.
Depth the Bit
Zero the bit back onto the board end and use the pin piece to
gauge the depth of cut.
Drop the bit, and you are ready to cut the tails.
Cutting the Tail Sockets
Do this carefully: because the cut is guided, you can cut from
both faces of the tail board, front first and then from the back.
This will ensure that there’s no breakout, specially if you go gently
and your bit is sharp. The end pins need special treatment as
you will need to trim the edges before cutting the exact socket
position. On the left edge go away (clockwise) around the board.
You have space for this.
On the right-hand edge come forward. You may need to lift the
18
8 does 8,10,12.
The Bit is placed over the board end and
the Drop Pin plate loosened and brought
up to the middle of the Islands.
The Drawing shows the wood tracked out
left to show the position of the Pin and
the Bit and the work in the CamLock,
and the Template reatiative to the
Bracket and Fence.
Pin and cut forward (clockwise again) making a half cut (trim cut) on
the edge of the board.
Put the router back and drop the DropPin again before making a full
cut down the alley between the islands.
Breakout
When making sockets, there is little breakout if you trim cut from the
front and then go round and make the full cut from the back of the
board.
If the boards are thin, you can cut them both at once, but it’s probably
best to do them one at a time, carefully, at first.
Select the pieces for grain and character and mark out which piece
goes where – whether Side (long) or End (short). The triangle marking
method is very useful to keep the boards in order.
The following is a way of keeping the sockets and the pins
exactly matched up corner for corner.
Put the two tail boards together, in the left hand, ready to go in the
CamLock, with the arrow pointing upward. Somersault the front board.
Now they have both inside faces facing you.
Keeping that orientation, lock the back board in the CamLock and cut
the row of top left sockets. Next the bottom right corner sockets of
the front board, which is now ‘upside down’ and at the top, because
you flipped the board.
The larger Pins look more crowded on
the board end, but it is a matter of
opinion when they look wrong.
At the smaller end of the scale, the
pins could look too widely spaced,
and need a Template with a tighter
pitch.
Put the boards together (don’t change the orientation) and cartwheel
the boards together. That is, look at them and wheel them through
180°.
Note: The Sides will now match up with the Ends with the pin when
they are rotated in this way. The pins have to have the thicker part
always facing the machine, and have to be cart-wheeled between
cutting one end and the other.
Now do bottom left corner sockets trim cutting from the front and then
cutting from the back that is from the outside to the inner face
19
and then repeat for the top right corner.
Remember:
1. Put them together and flip the front board. and cut both
rows together.
2. Cartwheel them both together and cut the other two. and
that’s the Tails done.
Making the Test Pins
DO NOT FORGET TO DO THIS...
...before you leave the tails, take a piece of good scrap a little
wider than the width of two sockets and cam it in place under
the bit which is brought forward to cutting position (off). Push
the router away, and squeeze the scrap up a fraction. Cam it
in again, and switch on. Bring the router forward so that the bit
cuts a shallow groove in the top of the scrap. Cut the first pin
position, and then the second making two shallow grooves.
It gives you both the bottom dimension and positions of the
first two tails.
Keep the Test Stick in place and...
Making the pins
...change the dovetail bit for a straight bit. The larger the better
(less break-out), but it must fit easily between the pins, and
also be right for the Template. We will check that next.
You now use the wedge shaped Islands on the template, Raise
the Pin.
Now track the Bit to the back edge of the test stick on the right
hand side of the groove so that the left blade is just touching
the right hand edge of the groove.
Unlock the Pin Plate (Pin down) and move it up so that the Pin
comes up against the wedge. Lock the Drop Pin Plate.
Track the Bit to the other side of the groove and align the right
hand blade with the left edge of the groove.
The Pin should come up and hit the wedge on the left just as
it did on the right-hand side.
The dovetail bit cuts two
grooves to trace the bit
diameter on the stick at
first and second socket
positions
If the Pin runs off the top end of the wedge, when the Bit
is placed, the bit is too small to hit the wedge so change the
bit for a larger diameter straight bit and start the test again:
loosen the drop pin plate and pull the plate forward allowing
you to place this larger bit on the edge of the groove. Slide
the pin away till it nudges the wedge.... and tighten the keys
on the Drop Pin.
Test the other side and check that the blade comes to the edge
of the groove. Do this without moving the sliding bar.
Dry Run
Before cutting the test stick, check that as you run the Pin
down the Wedge either side, the bit will run across the groove
from top right and down at a slope of 1 in 7 to make a pin
with the base the same size as the groove which is the same
size as the dovetail bit. Check that it runs over the stick the
other side also.
Making the Pins in the Test Stick
Now cut the test stick proper.
Zero the cutter onto the scrap and gauge the bit depth using
the piece with the dovetails cut in it.
Drop the bit, Track to the left hand edge of the Stick. Switch
on and make a right-hand cut, from the right side, just kissing
the corner of the groove sloping down towards the left, The
first pin will allow a right hand cut only.
Track to position number 2, and make a right-hand cut and
then a left-hand cut, from top left side down towards the bottom right. Be sure to clean the space between the pins. Don’t
worry about breakout until later.
The test stick should fit the first and second sockets on the
board with the sockets. And the two should line up on the left.
20
The bit is at the back
of the Stick just at the
edge of the groove. Slide
the Pin up to the wedge
till it gently nudges it,
and tighten the Locking Pins on the Drop-pin
Plate
A right hand cut
If it’s too tight, move the Pin Plate towards you, so that it uses a thinner
part of the wedge.
If it is too thin, move it up the wedge to thicken the Pin a fraction. Try the
test on the other end of the stick.
The Bit is placed at
the edge of the groove,
with the Pin up
Making the Run of Pins
Now try the run of pins for real. It helps to place the board with the tail
sockets in it, handy, so you can see what you are trying to make. Lay it flat
on the Channel top with the tails towards you. You are making pins to fit
these sockets. Note that the first pin is only cut on the right-hand side of
it, and you will be cutting away the wood and leaving a dovetail pin where
the space is...
So, starting on the left of the board: it’s a Right hand cut only, then
Right – Left, Right – Left, and so on to the last pin
and the last is only a Left....
...unless of course you have a different layout with a tail in the end of the
run instead of a pin. See asymmetric dovetails.
There’s a knack to getting it perfect, but it won’t take long if you take it
gently. This is not your hamfisted dovetail jig; it needs care and finesse!
The Pin Plate is loosened and,
the Pin moved up to touch the
wedge. The other side is
checked in the same way.
The drop pin plate is tightened.
This sets the position for making
the dovetail.
When cutting the pins try to put an even, gentle pressure on the Wedge
with the Drop-Pin as you bring it forwards, and make sure that your plates
and all sliding surfaces are polished and easy running.
Try the fit.
At the end of the run, lift the router and lift the DropPin. If the fit is right,
you’re ready to go ahead. If not put it back and adjust the fit and trim it
up.
Finding the Pathway
How you make the track through the work is up to you, but it’s worth precutting from the front edge, going clockwise in and out of the Wedges,
down cutting or climb cutting, to cut the front edge. Then there’s no tearout when you come to work down the Wedges from the back. You do the
majority of the cutting from the back so that the dust flies straight into your
extraction system.
You will find for yourself the best way of running around the pathways – working left to right or right to left. As with tenons, don’t rush it in the beginning...
you want to make a good job of it first, and become fast and good later.
You should find that the two pieces – pins and tails – fit hand in glove,
breakout free and square.
Asymmetry
You could want an asymmetrical layout for making drawers with cocked
beading, or because you just want it asymmetric, or because the size of the
box is critical but does not fit with the pitch of the template.
One end pin can be made larger.
Alternatively the end tail can be made larger.
Normal WoodRat dovetail techniques easily cope with asymmetry, but here
we resort to a bit of cunning.
If you have a bigger pin on one end than on the other, you will have to somersault the tail board so that the same edge is cut with the bigger pin.
But as is always the case, the pin board must be Cart-wheeled, to keep
its inner face against the machine face, otherwise you will get a zee/zed
instead of a square box.
Start by making pins on one pin board with its corresponding tail board.
Make the opposite corner with the other pin board and its corresponding
tail board. They will match up.
But now when you cartwheel each pin board to make pins in the other end,
you will need to move the template to get the pins in the right positions.
The size of the bigger pin (the position of the cut) is got from marking out
the big pin on the end of the pin piece as you would for hand cut dovetails,
placing the tail board over the end of the pin board. Mark the end pin position with a marking knife.
Place the marked up tail piece with its inner face against the machine face,
and relocate the template so that the bit will cut down the line of that bigger pin. Re-lock the Template. Now you can run the line of pins for the two
21
remaining corners.
Box with a Box Lid
The usual method of cutting off the lid part of a box through a
large pin is impractical with the Pathfinder.
You can cut the wood first and make two boxes one for the box
and the other for the lid, but you must be sure to make each part
to the same overall dimensions.
Alternatively, you could make the cut through one of the tails
between the pins.
A variation on this is to use the full MB3 MitreBox and Mitre the
tails so that the lid and box can be fitted together by rebating/
rabetting the lid into the box.
Grooves for Bottoms and Lids
The RP3 router plate has the usual slot on the left-hand side so
that it can act as a normal router plate when doing non-pathfinder
work.
So, when grooving for the box bottom and lid, simply place one of
your Starknobs (from the WoodRat/LittleRat kit) in the M8 tapped
hole in the HalfPlate and screw the plate down where you need it.
Take out the Cheeks etc. Place the Brush, and feed each piece
through by hand.
Remember: feed on the up-cut if widening the groove.
When feeding small pieces, you’ll need the blue block placed
in the yellow dust chute to stop the workpiece pushing into the
cutter gap.
To make a stopped cut to avoid the groove showing on the outside
off the joint, set the brush down a little from the bit (for protection),
and carefully lift the workpiece up into the cutter at the beginning
of the slot. Feed the workpiece along under the plate cutting the
groove, and drop it when it reaches the end of the groove before
it breaks through the joint.
This takes a little practice, so try it on some scrap first.
Thicknessing the Bottoms
Having run the groove you can thickness the box bottom to fit
the groove by resetting the bit and running the bottom past the
cutter to rebate it, as for normal Woodrat practice.
22
Because the pitch is fixed by the Template, you will need to design
the drawer heights to match the available socket positions on the
template. If the pitch is unsuitable turn the template and try the
pitch on the opposite set. The diagram at the end of this section
will help with the design.
The Drawer Side is mounted vertical, with its inner face against
the machine.
The Drawer Front is horizontal up under the HalfPlate and the
Template with the inside face up, and the two are cut in one
pass... first a series of forward cuts to make the sockets without
tearout, then a pass, down cutting the tails, and then cutting the
pin pockets between the pins of the Drawer Front. This is all done
with the same dovetail bit.
23
The D
A series of oak and sycamore
drawers made
with an early version of the Pathfinder Half-Blind
Template.
24
Half-Blind or Lapped Dovetails
Drop Pin
Set up the MitreBox MB3 with
both left Cheek screwed to the
Fence and the Right one held
with the Rod Clamp
M6 Locking keys
Drop-Pin Plate
Dove-
Half-blind Dovetail Template
Locking Lever
Rod Lock
Bracket
Lobed Washer
Locking Keys
Spreader Rod to be stored
We have a third and very different Template
for lapped dovetails, with a different approach
to its joint. The two workpieces are mounted
together in the MitreBox and the same dovetail bit cuts both of them in one run. It enables
you to dovetail a reasonable sized drawer in
under 5 minutes, because there is no need
to chisel the back corners of the pin pocket
as in normal WoodRat half-blind dovetails. It
is very quick. The size of bit is given by the
thickness of drawer front and is less critical
than that for through dovetails, as the lap can
vary. Having two differing pitches on the same
Template allows a greater choice of dovetail
layout, and each template is designed for a
specific WoodRat dovetail bit.
Although intended for drawers, the half-blind
method also gives you full blind dovetails
which you can make into secret dovetails by
mitering them using the Mitrebox, and therefore you can make boxes with continuous perfect figured grain with no visible joints.
25
tail Bit to use
You would expect to select the bit to match the thickness of
The drawer Side is held vertical and the
Front is horizontal. between the Cheeks of
the MitreBox. The Template (shown faded) is
held by the Bracket and goes with the wood.
The Bit goes with the plate and the Pin
directs the Bit around the back of the Side
to form the Tails and then into the Front to
make the pin pockets. It’s all done with the
same Bit at the same depth. The spacer is
not shown
The Cam Lock holds the two Cheeks apart,
but is able to squeeze together to lock the Front
in place. The handle provides a quick release with a half
the drawer front and to allow a nice balance between pin and
drawer side when it shows as you open the drawer.
But, each Half-Blind Template works with only one size of
dovetail bit. Choose bit that corresponds with the Template.
Interestingly one Template can give a range of results.
One Bit, one template, but three very different results
show that there’s lots of room for individuality.
If you have a range of Templates choose the one that is intended for the bit you intend to use.
Set-Up
Add the second (right-hand) cheek for half-blind dovetails, as
the drawing above.
Place a drawer side vertically up under the plate and against
the machine face. Cam it in, but not tightly.
The Rod Clamp
Set up the clamping system on the threaded rod as shown in
the illustration.
The Rod Clamp needs to hold the drawer front firmly, up under
the HalfPlate, in a way that when you loosen the Hand Lever
by half a turn you can slide out the Front piece and slide in
26
1. A rather heavy
drawer front
2. A classic
design solution
2. A thin drawer
front and weak
looking outer pins
Park Position
Place the tail vertical
The Separating Stick spaces the Side
and the Front a repeatable distance apart.
The Front is pushed up against the plates
above and against the stick.
The Drop Pin is up and off to the right taking the Bit
up to the Park Position
Each HB Plate is made for a particular 1in7 dovetail
bit and has a fixed pitch. But there are two different
pitches on each plate which gives a wider choice of
width to match the boards to.
The half-plate and router plate are not shown.
the next without snagging, and tighten it so that it does not
move under pressure from the cutting action, which will be
pushing into the end-gain.
So loosen all the inner nuts and washers, and with the hand
lever with the lever towards you, tighten the Big Lobed Washer
so that the Drawer Front – lifted up close under the plates – is
firmly held. Loosen the Hand Lever and slide out the Front.
Slide it back again and tighten, and make sure that the work
piece is firm and will not be dislodged when attacked by the
bit.
Rubber washer Sandwich
Tighten the back nut on the Lobed Washer Nut. Then the pair
of nuts (nut and lock nut) on the rubber washer sandwich,
squashing it so that when you push the lever away, the rubber
washers push on the Cheek, releasing the Drawer Front and
giving room for the next one to be slid into place.
You’ll need to push upward on the Drawer Front to make good
contact with the HalfPlate, which will ensure that the Front
dovetails have the same depth of cut as the Side, which is
slid up vertically under the Half-plate.
When all is running nicely we find that it’s best to put the
Drawer Front in first - horizontal, then the Side - vertical,
pushing it up under the Plate and Camming it in loosely. Then
lift the Front and tighten the Hand Lever and then retighten
the CamLock on the Side.
Making Classic Drawers
The Pathfinder allows you to make drawers with all the
characteristics of a classic, craftsman’s piece – fine
dovetails, thin drawer sides, sliding drawer bottom,
etc., but in a fraction of the time.
1. Preparation of work-pieces
The better you prepare your work, making the ends of the
Side and Front square and true, and the inner surfaces flat
as can be, the better will be the joint. All the three boards
27
of the drawer (two sides and one front) need to be as far as
possible the same width. The drawer Back should be made
at the same time to the same thickness and cut down only
after it is jointed.
The Drop-pin is placed in the router plate and anchored with
the Locking Screws. Loosen the plate to change the position
of the Pin, forward and back, relative to the Bit. There are three
pairs of holes for the M6 Locking Keys.
The Drop-Pin runs around the tail islands and then the pin
pocket recesses in the Template in the same pass as the Bit
is cutting the drawer sides, and then the pin pockets, all at
the same depth. This makes it a simple operation, once it is
set up.
You may need to design the drawers to accommodate the
template to some extent, but each template has two different
pitches, for the same dovetail size, so it should not be hard to
find a pitch that’s very close to the height of drawer front you
need. The full-size diagram of the possible dovetail runs at the
end of this section should help with the layout.
2. Getting to work
Unless you are doing asymmetrical work like for cock beaded
drawers you can ensure that you make a perfectly symmetrical
arrangement. Take the centre of the board, and match it with
either the centre of the run, or exactly between two pins.
Use the Template and put it the right way round to give you
pitch A or the larger B as right for your design.
Place a piece for tails (a Side) with the inner face against the
face of the WoodRat and the corresponding Drawer Front horizontal, up under the plates, with the inner face facing up.
The CNC-cut, Half-Blind Template allied to exactly machined
dovetail bits gives a close fit of pin to tail, that is when the
depth of the bit is just less than the full depth by 0.5mm or
less. Adjusting the depth gives just enough leeway in the fit,
provided that you use a WoodRat 1in7 dovetail bit.
The template gives exact alignment of pins to sockets, so that
the boards marry up exactly.
This only leaves the depth of the Side, after it has been cut
with tails, to the depth of the pin pocket. And this needs careful
setting, so that there is a minimum of final cleaning up.
The Half-blind Layout
Mark the centre line of your board and note whether the pins
will be odd or even in number, and camlock the board in vertically with the inner face against the machine face.
Fit the Template with its two Locking keys in ready, and slide
it into the Bracket. Don’t tighten yet.
Track the board to line up its centre line mark with the Bit (with
its blades north/south). Then slide the Template to line it up
under the Drop-Pin, aligning the Template with either the corresponding alley (odd number of sockets), or the middle of the
Island (even number). Tighten the Template Locking keys.
Track west and east to check that the two ends of the run look
right, with the Bit covering the two ends equally at both edges
of the Drawer Side.
A. Even number of sockets: Bit lined up
on the centre line of the board, and the
Template moved to position the Pin to
the middle of the island.
The Layout
Take extra/spare pieces of Side and Front. Place them in the
Pathfinder.
A B
Place the Side vertical, with its inner face against the machine
face.
Place the Front (inside up), up under the Half-plate. Hold it
there with the RodLock.
Follow this: making sure you can see the bit clearly.
1. Unlock the router, zero the Bit onto the end of the Drawer
Side and depth the router to the depth of the bit using the scale
on your router, and not to the depth of the wood as with through
dovetails. Set it to the blade length of the Bit, and then unscrew
the depthing foot a couple of half turns. The depthing is now
a little less than the blade length. For example depth the 12-6
bit to 12mm and give it a couple of downward turns.
28
B. Odd number of sockets: Bit lined
up on the centre line of the board, and
the Template moved to position the
Pin between the islands
WR-8-7-20-10
The cutter is at the
line on the top of the
drawer side.
The Drop pin is placed
in the Template at the
front edge of the socket island.
The drawer front up
under the template,
held by the Rod Lock
The drawer side is held
by the Cheeks and the
CamLock
Fig 27.1
27.2/3. Track the Board away left, and Plunge the router fully.
Move the router (Pin up) to line up the flat of the Bit square against
the board end. The drawing shows the position of the Bit when
plunged, where the cut at the neck just leaves the full thickness
of the board on its end.
2. Bring the Bit forward – the blade depth/length
divided by 7 (slope number of Bits). Put the Pin
to the back of the Island and lock down.
1. Drawer Side is used to mark the
thickness of the Drawer Front on the
inside face, with knife or sharp pencil.
T
L
T
Use another piece to measure out the thickness of the Drawer
Side board onto the inside (upside) face of the Drawer Front,
and draw a line against the board with a sharp knife or pencil
(fig 28.1).
2. Lift the Bit. Track the wood under it and drop the bit onto the
end of it. Bring the Drop pin to the north face of the island for the
tails as shown, and lock the Drop-Pin plate to the RouterPlate.
When you later drop the Bit again on the left of the workpiece,
it will cut along the back of the islands making the tails, which
will be the full thickness of the drawer side at their widest, at the
top of the board.
L/7
4. Lift the Pin, and bring it to the back of one of the Pin
Pockets. This brings the router Bit forward to the back of the
pocket cutting position on top of the drawer front but first...
note that when the Bit is dropped to depth,
the neck will just graze the top back edge of
the Side board. Which is the same distance T
that the pencil mark is into the drawer Front.
Fig 27.2
5. Push the Drawer Front forward so that the point of the bit
(aligned north/south) lines up with the line on the drawer Side.
Tighten the RodLock handle. This puts the back of the pocket
under the bit at its position to cut the back of the pocket. Now
tighten the CamLock.
Plan view of the Bit against
the end of the Drawer Side
End view of the Bit against
the end of the Drawer Side
6. Making the Spacer Stick
This is the best time to make a spacer stick to act as a spacer
between the Side and End. It sits on the two MB3 Cheeks in front
of the drawer side, and needs be thin enough to lie beneath the
sockets as they are being cut yet catch the bottom edge of the
Drawer Front to act as a Stop. Accurately made, the Stick should
now slot in between the Side and the Front. It should be about
8mm thick, longer than the width of the boards and exactly the
width of the space between the Side and Front.
7. Release the Drawer Front again and push it forwards firmly
against the Stick and up under the Half-plate, so that it holds the
Side in place, making sure all is firm. The Spacer now makes a
repeatable distance between Side and End.
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The cutter is already depthed so drop the bit, and you’re ready
to go.
1. The bit lines up
against the edge
of the board, and
t
2. the work and
template are moved
so that the Pin
can line up against
the island
t
3. the Pin is
placed against
the north face
of the island
t
The Drop-Pin is
brought forward to
the back of the Pin
Pocket. Bringing
the Bit with it.
t
t
5 The Drawer Front
is pushed forward
so that the mark
lines up with the
front blade of the
Bit
6 The Separating
stick is made to fit
between the Side
andn the End to
make a repeatable
distance between
them.
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1. Bit cuts sockets from the front.
Pin goes across the front of the
Islands and up into each alley.
4. The Bit now comes forward,
and runs down the left of the
first pin and back out.
2. Bit trims the edge and then
cuts along the back, downcutting
the inner face of the Side.
5. It then goes right, down-cutting
the face to the right, then in again
and cleans the back of the pocket
Cutting the Tails
The correct direction of the cut is a matter of opinion (which
means that no-one has worked out the best way yet). This
is one way:
Start by going from the Park position (Bit down) at top right
with the Pin up. Cut a trim cut for the right-hand end socket,
then drop the Pin again.
1. Go up into each socket position to eliminate breakout
from the front.
2. Then work back, first giving a trim cut to the first socket
away towards the back (remember that you always try to run
clockwise to down/climb cut your work). Then skim, clockwise, right, across the back of the board.
3. and then, up-cutting again, trim each tail carefully with its
rounded corners, back to the left hand end again and into
the space between sockets and pins.
The Pin Pockets
4. Now travel down into the left hand edge of the first, lefthand pocket, into the end grain.
3. Then carefully back forming
the rounded corners and
connecting with pre-cut sockets
6. Then on to pocket #2, running
down the right side of the prong,
and off right again, and so on...
5. Then go back out and right, across the open side of the
pocket (down cutting, to avoid breakout), then down the right
hand edge of the pocket, and again left, across the back of
the pocket, then back out, clearing any waste, and on to the
next pocket...
6. Go down the left hand edge of the next pin, out across
the open part of the pocket and down the right hand edge,
across the back of the pocket, and on to the next pin pocket.
and so on to the finish.
There are other ways, but we stress again that it is best to
cut carefully first and fast later. Remember that the neck of
a dovetail bit has very little cutting edge and simply cannot
go fast: specially into end-grain.
The Fit
Now try the fit. It should be pretty accurate.
You get the exact fit of pin to socket by raising (loosening the
fit) a fraction, or lowering the Bit (tightening), and trying again.
Use the fine adjustment on the depthing foot for this.
Now look at the depth of the Side in the pin pocket. Chances
are that the depthing will not be quite exact. Decide whether
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the Side should be thicker (in other words the side lies too low in
in the pocket, or too thick in the pocket and stands proud.
Say it is too thick by 1mm: You could of course plane it off, but
there’s a better way.
When you make the next trial, put the whole set-up back together
ready, with the stick in front of the drawer side, and the drawer
front pushed in against it.
Then loosen the Locking keys and pull the Drop-Pin Plate forward
by half a millimeter measured against the scale on the RouterPlate.
This will make the Side Tails one half mill thinner and the Pin pocket
one half mill deeper with a net change of 1 mm.
If the Side stands proud of the Front by
1mm, move the Pin Plate forward by 0.5mm to
decrease the depth of the tail and at the same
time increase the depth of the pocket
Conversely, if the drawer side is too deeply set, the Drop Pin Plate
needs to be reset away from you by half of the over-depthing,
because, as the bit moves away from you, it makes the tail at
the same time thicker, and the pocket shallower. So it is quite a
subtle adjustment.
When drawer side, stick and drawer front are cammed in place,
the whole structure should be solid, square, and ready for work.
Make sure that the drawer side lies flat against the machine face,
and that the inside face of the front is flat up under the half-plate.
Push upward with the fingers of the left hand before tightening
the Camlock and the Hand Lever.
Remember, the object is to track the minimum route, leaving nothing behind and causing no breakout. It is tempting to go fast, but
we advise building up speed gradually, when you are sure of your
method.
The two pieces should come out from the cheeks and lock together
exactly, ready for glue.
Trouble shooting
Mis-match of boards
One crucial thing, especially with drawers, is the way the two pieces
marry up. Planing them up to correct a mismatch tends to make
the perfectly square drawer front into a parallelogram shape, which
does not properly fit the drawer opening. This should not happen
as you benefit from CNC cut Templates and they should be perfect,
but they will not fit exactly if the boards are of different width.
Slipping workpieces
WoodRat do not sandpaper the faces; we leave this job to you.
When applying sandpaper, use a synthetic rubber cement like
Copydex or the US equivalent which is easy to remove and replace
when needed.
The Pathfinder is very much “work in progress”. These three Templates demonstrate what is possible. What we actually make as the
next generation of Templates will depend on demand from you....
Let us know what you think.
32
1mm oversize
Chart of Tails Layout for the 12-6 Bit
2A
12-6 at 24
2B
12-6 at 26
This is a full sized drawing of the half-blind template 2 and the resulting
drawer layout. The blue lines represent the layout for when the pitch is
24mm -2A and the red lines show the different layouts for the 26mm
pitch.- 2B. You can make some drawers with layout A and some with B as
it suits the plan. Start measuring from the bottom line.
layout for a cock-beaded
drawer using the 24mm
pitch HB Template.
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Using the MitreBox
The full MitreBox will allow you to cut accurate 45° angles across the ends of the four pieces
of a box, as well as hold work at any required angle.
WR-8-7-20-10
Mark out the work with a sharp pencil or knife. Arrange the Box
with the two Cheeks held apart with the Rod Clamp and the
Spreader Rod so that the workpiece can slide between them.
Use a 45° set square to check the angle, and then tighten the
CamClamp to hold the work square and firm.
Like this, a variety of mitred joints can be cut, but for Secret
Dovetails we need to mitre the Set up the MB3 as for Half-
Blind dovetails. You will need a 45° bevel or, better, a
45° triangle set square.
Place the work inside up, with the 45° set to make the angle
between workpiece and the underside of the plates.
The 45° line determines the
depth of the Bit for cutting
tail sockets. Cut away the top
of the board. Make the gauging piece to be the thickness
of this cut away part.
The HB Template you use will determine the bit needed,
as each Half-blind Template is designed to work with its
own WoodRat bit.
Using that dovetail bit, cut the mitres at each edge, and along
the back edge. Repeat for each of the other seven board
ends.
Next put each Side piece in vertically and reduce the board
end as shown (fig 32.2). Measure the dovetail bit’s blade length
(less a 0.5mm) up from the 45° line.
Cutting away this part will allow the Bit to cut to full depth down
to the 45° line when making tail sockets.
The Gauging Piece
See from figure 33 that the Side and End will be cut with the
same cutter but at two different set depths: the Side with the
bit depthed to the full board thickness, but for the Ends the Bit
is depthed to the bit blade depth (less a fraction).
It’s worth making a gauging piece that is the difference between the board width and the cutter blade length. It will give
you the exact gauge between cutting the tails (without the
34
gauging piece
The 45° line projected
from the corner and
taken across the face
of the board
(fig. 32.2)
2. The neck of the bit is
aligned with the corner of the
joint, and the Pin is dropped
on the north face of an
island. aa
4. The Bit is dropped to depth
(the length of the blade). The gap
between the boards needs a
separating stick.
T
1. The Bit is
depthed to the
thickness of the
workpiece
5. The thickness of the gauging
piece is as between the bit and
the underside of the work It
gauges the raising of the Router
between making the Tails and
making the Pin pockets.
3. The Pin is brought forward
to the back of the pocket,
and the Bit dropped gently
onto the workpiece. The work
is slid under the Bit, aligning
the point of the blade with
the line at 45°
6.Depth the Bit to the full thickness of
the workpiece. Cut the tail sockets, and
round the corners, Cut from behind,, and
stop the cut
35
gauge) and the pin pockets (with the gauge) later.
The same rule applies for secret dovetails as for through
dovetails: The Ends (the shorter boards) take the pins
or in this case the pin pockets, and the Sides take the
tail sockets.
Note that the fit of the tail to pin will be determined by the accuracy of this gauge because it determines the depth of the
pin pocket. The thinner the gauge, the deeper the pins, and
the tighter will be the fit.
And vice versa.
Placing the tail sockets and pins
The set-up for cutting mitred dovetails is basically the same as
for half-blind dovetails, but there are differences:
Find the two pieces that make a corner from the arrow marks
in the usual way.
Place the Tail Piece vertical, with its inside face against the
machine face, and the End with its inside face, facing up,
under the plates, and with a gap between the vertical and the
horizontal boards.
Find the centre line of the work-piece board. Align that centre
with the Template so that at least two pockets lie comfortably
within the width of the work-piece, and there is enough mitred
edge for whatever purpose (rebating and/or moulding) as the
design needs. Zero the bit carefully onto the top surface of
the End, and depth the router to the boards’ thickness (all the
boards should have the same thickness).
Track the work away from the Bit to the left. Turn the blades
north/south, and pull the router gently forward and track the
wood back right so that the wood just touches the face of the
bit blade. Now position the blade so that its edge just intersects the top inner face of the socket block. This is shown in
the diagram figure 33 Step 2.
Loosen the Drop Pin plate, drop the pin and bring it against the
north face of one of the islands, (track the wood and template
to the left if necessary to do so) and tighten the Locking
Keys.
Raise the Bit.
Raise the Drop Pin, and bring the router forward, drop the
Pin into the pin pocket, and register it at the back of the pin
pocket. Slide the box End forward under the blade of the bit
so that the line drawn when you marked out the 45° on the
boards lies at the tip of the bit. Push the End up firmly dunder
the plates and lock the boards in place. Everything is now ready
to run, but take the measurement between the two boards for
the spacer stick before you disturb the set up.
Cutting the Tail Sockets
Run the Tails sockets with the Bit depthed without the gauging
block, but depthed using the work-piece. Run the row of tails
as you would do the H-B’s but contained within the mitred
edges, and without cutting the front of the board of course.
Stop the cut as you pull forward from the back face until the
Bit hits the rising plane of the mitre. It will not be able to cut
through to the front face in any case. Cut along the back edge
to undercut
Cutting the Pin Pockets
For the Pins, raise the router (don’t alter the depthing foot) and
drop it again gently onto the gauging piece. Run around the
pins and cut out the pockets. The Drop-pin will run along the
tines of the template pockets. This might mean that the pins
themselves could be a little too long.
It is possible to customise the length of the tines, but this
might not be good for half-blind dovetails done later with the
same template.
If the mitered surfaces don’t come together it could be that the
pins are too long. A simple solution is to raise the Pin and cut
across the front end of the pins to shorten them.
The two boards should fit together nicely. If it’s a loose fit as
you put them together, you can drop the bit a small amount
36
to tighten the fit for the next corner. Do this by removing a
small amount from the gauging piece to deepen the cut. Do
not alter the depthing foot. This is still set to the thickness of
the boards.
Do not forget to use the gauging piece for the Pin Pockets and
to remove it for the Tail Sockets in each of the four corners,
and be careful to use your arrow marks to get the right pieces
to the right corners.
As you put the boards together you will see that the pattern of
grain will run continuously around the ring.
37
Published in England by WoodRat Publications
Printed by Paper Tiger Press
©˙Martin Godfrey January 2010
Godney BA5 1RY UK
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