Cutting the Tenon
When cutting mortises fit the
2-1/8 inch collar fitted to the 1 inch
guide bush, then select and fit the
appropriate cutter from the chart on
the set-up bar.
Setting Up
A centre line is drawn across the end
of the timber before it is clamped
lightly in the jig. Both ends of the
tenon and the tenon length are marked
(i.e. cutting depth). These dimensions
may not be equal when cutting angled
or compound tenons.
Lay the setting bar flat on the template
end plates and set the timber against
the edge of the downstand to set the
height. Then use the setting bar to
centre the timber across the template
opening.
Select the required tenon width lines
on the set-up bar and align them with
the tenon end marks. Slide the end
plates up to the template line (marked
L and R) and lock the plates in
position.
When cutting tenons, use a 5/8 inch
diameter cutter and select the
appropriate guide bush from the chart
on the set-up bar.
Cutting the Mortise
Position the router on the top plate
and set the depth of cut (i.e. tenon
length) on the router’s depth stop.
Feed the router smoothly in a
clockwise direction, keeping the guide
bush against the template edges.
Plunge cut the tenon in a series of
shallow passes.
Square end tenons can be cut by
simply reversing the end plates. The
mortise ends will then need to be
squared with a chisel.
To cut angled tenons, set the vertical
guide to the required angle (see main
picture), butt the timber against it and
clamp the timber. To cut compound
angle tenons, set both the vertical
guide and the tilting back plate to the
required angles.
Leave the end plates as set for cutting
the tenons. Align and clamp the timber
horizontally and tight to the underside
of the top plate. Set the cutting depth
slightly deeper than the tenon length
and cut the mortise in a series of
shallow passes.
When using thin timber sections or
when clamping one end only, clamp a
support batten beneath the mortise
timber. Other clamp positions are
available in the back plate to ensure
that all timber lengths can be held
securely. IP
The Mortise and Tenon Jig can also be used for drilling
dowel holes using the guide bush positions in the template
end plates. To position the cutter (diameter equal to
dowel diameter), draw the centre lines and dowel centres
on the two pieces of timber to be joined. Align them with
the notches on the template guide holes. Fit the 5/8 inch
guide bush and the cutter to the router and set the
cutting depth to slightly more than half the dowel length.
Drill the holes in a series of plunge cuts to prevent the
waste from packing around the cutter. Fit the second
piece of timber and drill the dowel holes as before.
Spring 2002
All prices are exclusive of VAT
9